EventBus | Event bus for Android and Java that simplifies communication | Pub Sub library

by greenrobot Java Version: V3.3.1 License: Apache-2.0

Download this library from

kandi X-RAY | EventBus Summary

EventBus is a Java library typically used in Messaging, Pub Sub applications. EventBus has no bugs, it has no vulnerabilities, it has build file available, it has a Permissive License and it has medium support. You can download it from GitHub, Maven.

Prepare subscribers: Declare and annotate your subscribing method, optionally specify a [thread mode](https://greenrobot.org/eventbus/documentation/delivery-threads-threadmode/):. Read the full [getting started guide](https://greenrobot.org/eventbus/documentation/how-to-get-started/). There are also some [examples](https://github.com/greenrobot-team/greenrobot-examples). Note: we highly recommend the [EventBus annotation processor with its subscriber index](https://greenrobot.org/eventbus/documentation/subscriber-index/). This will avoid some reflection related problems seen in the wild.

Support

Quality

Security

License

Reuse

kandi-support Support

EventBus has a medium active ecosystem.
It has 23725 star(s) with 4635 fork(s). There are 1093 watchers for this library.
There were 2 major release(s) in the last 12 months.
There are 103 open issues and 451 have been closed. On average issues are closed in 107 days. There are 41 open pull requests and 0 closed requests.
It has a neutral sentiment in the developer community.
The latest version of EventBus is V3.3.1

EventBus Support

Best in #Pub Sub

Average in #Pub Sub

EventBus Support

Best in #Pub Sub

Average in #Pub Sub

quality kandi Quality

EventBus has 0 bugs and 0 code smells.

EventBus Quality

Best in #Pub Sub

Average in #Pub Sub

EventBus Quality

Best in #Pub Sub

Average in #Pub Sub

security Security

EventBus has no vulnerabilities reported, and its dependent libraries have no vulnerabilities reported.
EventBus code analysis shows 0 unresolved vulnerabilities.
There are 0 security hotspots that need review.

EventBus Security

Best in #Pub Sub

Average in #Pub Sub

EventBus Security

Best in #Pub Sub

Average in #Pub Sub

license License

EventBus is licensed under the Apache-2.0 License. This license is Permissive.
Permissive licenses have the least restrictions, and you can use them in most projects.

EventBus License

Best in #Pub Sub

Average in #Pub Sub

EventBus License

Best in #Pub Sub

Average in #Pub Sub

build Reuse

EventBus releases are available to install and integrate.
Deployable package is available in Maven.
Build file is available. You can build the component from source.
Installation instructions are not available. Examples and code snippets are available.
EventBus saves you 2836 person hours of effort in developing the same functionality from scratch.
It has 5811 lines of code, 567 functions and 104 files.
It has low code complexity. Code complexity directly impacts maintainability of the code.

EventBus Reuse

Best in #Pub Sub

Average in #Pub Sub

EventBus Reuse

Best in #Pub Sub

Average in #Pub Sub

Top functions reviewed by kandi - BETA

kandi has reviewed EventBus and discovered the below as its top functions. This is intended to give you an instant insight into EventBus implemented functionality, and help decide if they suit your requirements.

Checks for subscribers that are visible to the given package .
Creates a new subscription .
Find methods in single class .
Handles a message .
Map a throwable to a specific error message id .
Executes the given Runnable .
Maps a log level .
Checks if Android is available
Gets the super subscriber info .
Returns a pending post .

EventBus Key Features

Define events: ```java public static class MessageEvent { /* Additional fields if needed */ } ```

Prepare subscribers: Declare and annotate your subscribing method, optionally specify a [thread mode](https://greenrobot.org/eventbus/documentation/delivery-threads-threadmode/): ```java @Subscribe(threadMode = ThreadMode.MAIN) public void onMessageEvent(MessageEvent event) {/* Do something */}; ``` Register and unregister your subscriber. For example on Android, activities and fragments should usually register according to their life cycle: ```java @Override public void onStart() { super.onStart(); EventBus.getDefault().register(this); } @Override public void onStop() { super.onStop(); EventBus.getDefault().unregister(this); } ```

Post events: ```java EventBus.getDefault().post(new MessageEvent()); ```

EventBus Examples and Code Snippets

See all related Code Snippets

EventBus in 3 steps

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```java
public static class MessageEvent { /* Additional fields if needed */ }
```

Add EventBus to your project

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implementation("org.greenrobot:eventbus:3.3.1")

How can I redirect a user to login when a certain link is clicked using JWT

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import React, { useEffect } from 'react';
import { Navigate } from 'react-router-dom';
import { useSelector } from 'react-redux';

function Uploads() {
  const { user: currentUser } = useSelector((state) => state.auth);

  if (!currentUser) {
    return <Navigate to='/login' replace />;
  }
  return (
    <>
      <h1 className='page'>UPLOADS</h1>
    </>
  );
}

export default Uploads;

import { Navigate, Outlet } from 'react-router-dom';
import { useSelector } from 'react-redux';

const PrivateRoutes = () => {
  const { user: currentUser } = useSelector((state) => state.auth);
  return currentUser 
    ? <Outlet />
    : <Navigate to="/login" replace />;
}

<Routes>
  <Route path='/' element={<Home />} />
  <Route element={<PrivateRoutes />}>
    <Route path='/create/upload' element={<Uploads />} />
    ... any other protected routes ...
  </Route>
  ... other unprotected routes ...
</Routes>

-----------------------

import React, { useEffect } from 'react';
import { Navigate } from 'react-router-dom';
import { useSelector } from 'react-redux';

function Uploads() {
  const { user: currentUser } = useSelector((state) => state.auth);

  if (!currentUser) {
    return <Navigate to='/login' replace />;
  }
  return (
    <>
      <h1 className='page'>UPLOADS</h1>
    </>
  );
}

export default Uploads;

import { Navigate, Outlet } from 'react-router-dom';
import { useSelector } from 'react-redux';

const PrivateRoutes = () => {
  const { user: currentUser } = useSelector((state) => state.auth);
  return currentUser 
    ? <Outlet />
    : <Navigate to="/login" replace />;
}

<Routes>
  <Route path='/' element={<Home />} />
  <Route element={<PrivateRoutes />}>
    <Route path='/create/upload' element={<Uploads />} />
    ... any other protected routes ...
  </Route>
  ... other unprotected routes ...
</Routes>

-----------------------

import React, { useEffect } from 'react';
import { Navigate } from 'react-router-dom';
import { useSelector } from 'react-redux';

function Uploads() {
  const { user: currentUser } = useSelector((state) => state.auth);

  if (!currentUser) {
    return <Navigate to='/login' replace />;
  }
  return (
    <>
      <h1 className='page'>UPLOADS</h1>
    </>
  );
}

export default Uploads;

import { Navigate, Outlet } from 'react-router-dom';
import { useSelector } from 'react-redux';

const PrivateRoutes = () => {
  const { user: currentUser } = useSelector((state) => state.auth);
  return currentUser 
    ? <Outlet />
    : <Navigate to="/login" replace />;
}

<Routes>
  <Route path='/' element={<Home />} />
  <Route element={<PrivateRoutes />}>
    <Route path='/create/upload' element={<Uploads />} />
    ... any other protected routes ...
  </Route>
  ... other unprotected routes ...
</Routes>

How do I implement a Logout functionality from a React Router Link to imports an array?

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const Logout = () => {
  const dispatch = useDispatch();
  const navigate = useNavigate();

  useEffect(() => {
    dispatch(logout())
      .then(() => {
        navigate("/", { replace: true });
      });

  }, []);

  return <LoadingSpinner />;
};

...
import Login from './components/pages/Login';
import Logout from './components/pages/Logout';
...

...

<Router>
  <Navbar />
  <Routes>
    <Route path='/' element={<Home />} />
    <Route path='/my-account' element={<Account />} />
    <Route path='/login' element={<Login />} />
    <Route path='/logout' element={<LogOut />} />
    <Route path='/profile' element={<Profile />} />
  </Routes>
  <Footer />
</Router>

-----------------------

const Logout = () => {
  const dispatch = useDispatch();
  const navigate = useNavigate();

  useEffect(() => {
    dispatch(logout())
      .then(() => {
        navigate("/", { replace: true });
      });

  }, []);

  return <LoadingSpinner />;
};

...
import Login from './components/pages/Login';
import Logout from './components/pages/Logout';
...

...

<Router>
  <Navbar />
  <Routes>
    <Route path='/' element={<Home />} />
    <Route path='/my-account' element={<Account />} />
    <Route path='/login' element={<Login />} />
    <Route path='/logout' element={<LogOut />} />
    <Route path='/profile' element={<Profile />} />
  </Routes>
  <Footer />
</Router>

How can I change this Navbar dropdown item to update from "Login" to "Logout" when a user logs in?

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{subNav.title==='Login'?(userLoggedIn?'Logout':'Login'):subNav.title}

-----------------------

export const NavItemsList = [
    ...
    {
        title: Account,
        path: '/my-account',
        cName: 'nav-links',
        subNav: [
            {
                title: 'Login',
                path: '/login',
                cName: 'dropdown-link',
                menuName: 'account-menu',
                authenticated: false,
            },
            {
                title: 'Logout',
                path: '/logout',
                cName: 'dropdown-link',
                menuName: 'account-menu',
                authenticated: true,
            },
            {
                title: 'Profile',
                path: '/profile',
                cName: 'dropdown-link',
                menuName: 'account-menu',
            },
        ],
    },
    ...
];

function Dropdown({ submenus }) {
  const { user: currentUser } = useSelector((state) => state.auth);

  const [click, setClick] = useState(false);

  const handleClick = () => setClick(click => !click);

  return (
    <ul
      onClick={handleClick}
      className={click ? 'dropdown-menu clicked' : 'dropdown-menu'}
    >
      {submenus
        .filter(({ authenticated }) => {
          if (authenticated !== undefined) {
            return !!currentUser === authenticated;
          }
          return true;
        })
        .map((subNav) => (
          <div key={subNav.path} className={subNav.menuName}>
            <li className='dropdown-links'>
              <Link
                className={subNav.cName}
                to={subNav.path}
                onClick={() => setClick(false)}
              >
                {subNav.title}
              </Link>
            </li>
          </div>
        ))
      }
    </ul>
  );
}

-----------------------

export const NavItemsList = [
    ...
    {
        title: Account,
        path: '/my-account',
        cName: 'nav-links',
        subNav: [
            {
                title: 'Login',
                path: '/login',
                cName: 'dropdown-link',
                menuName: 'account-menu',
                authenticated: false,
            },
            {
                title: 'Logout',
                path: '/logout',
                cName: 'dropdown-link',
                menuName: 'account-menu',
                authenticated: true,
            },
            {
                title: 'Profile',
                path: '/profile',
                cName: 'dropdown-link',
                menuName: 'account-menu',
            },
        ],
    },
    ...
];

function Dropdown({ submenus }) {
  const { user: currentUser } = useSelector((state) => state.auth);

  const [click, setClick] = useState(false);

  const handleClick = () => setClick(click => !click);

  return (
    <ul
      onClick={handleClick}
      className={click ? 'dropdown-menu clicked' : 'dropdown-menu'}
    >
      {submenus
        .filter(({ authenticated }) => {
          if (authenticated !== undefined) {
            return !!currentUser === authenticated;
          }
          return true;
        })
        .map((subNav) => (
          <div key={subNav.path} className={subNav.menuName}>
            <li className='dropdown-links'>
              <Link
                className={subNav.cName}
                to={subNav.path}
                onClick={() => setClick(false)}
              >
                {subNav.title}
              </Link>
            </li>
          </div>
        ))
      }
    </ul>
  );
}

only one child route displaying in react? displays component for a different route instead of its own

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<div className="container mt-3">
  <Switch>
    <Route path="/login" component={Login} />
    <Route path="/register" component={Register} />
    <Route path="/profile" component={Profile} />
    <Route path="/films/:title/:id" component={MovieDetailContainer}/>
    <Route path="/films/:title" component={MovieListComponent}/>
    <Route path="/user" component={BoardUser} />
    <Route path="/creator" component={BoardCreator} />
    <Route path="/admin" component={BoardAdmin} />
    <Route path={["/", "/home"]} component={Home} />
  </Switch>
</div>

EventBus implementation using Coroutines and LiveData

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with(viewModel) {
    eventsFlow.collectWhenStarted(viewLifecycleOwner, ::processEvents)
}

inline fun <T> Flow<T>.collectWhenStarted(
    lifecycleOwner: LifecycleOwner,
    crossinline action: suspend (T) -> Unit
): Job = lifecycleOwner.lifecycleScope.launchWhenStarted {
    collectLatest {
        action.invoke(it)
    }
}

val eventsFlow: Flow<DataClass> = flowEventBus
    .flowMessage()
    .shareIn(viewModelScope, SharingStarted.Lazily, 1)

-----------------------

with(viewModel) {
    eventsFlow.collectWhenStarted(viewLifecycleOwner, ::processEvents)
}

inline fun <T> Flow<T>.collectWhenStarted(
    lifecycleOwner: LifecycleOwner,
    crossinline action: suspend (T) -> Unit
): Job = lifecycleOwner.lifecycleScope.launchWhenStarted {
    collectLatest {
        action.invoke(it)
    }
}

val eventsFlow: Flow<DataClass> = flowEventBus
    .flowMessage()
    .shareIn(viewModelScope, SharingStarted.Lazily, 1)

-----------------------

with(viewModel) {
    eventsFlow.collectWhenStarted(viewLifecycleOwner, ::processEvents)
}

inline fun <T> Flow<T>.collectWhenStarted(
    lifecycleOwner: LifecycleOwner,
    crossinline action: suspend (T) -> Unit
): Job = lifecycleOwner.lifecycleScope.launchWhenStarted {
    collectLatest {
        action.invoke(it)
    }
}

val eventsFlow: Flow<DataClass> = flowEventBus
    .flowMessage()
    .shareIn(viewModelScope, SharingStarted.Lazily, 1)

Generic Method in Java with out parameters

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        public <T extends IntegrationEvent, TH extends IntegrationEventHandler<T>> void subscribe(java.lang.Class<T> tClass, java.lang.Class<TH> thClass) {

        }

How can I configure my event bus in ASP.NET Core 6 - Migration to .NET 6

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var builder = WebApplication.CreateBuilder(args);
builder.Services.AddTransient<IEventBus,EventBus>();


ServiceProvider serviceProvider = builder.Services.BuildServiceProvider();
var eventBus = serviceProvider.GetRequiredService<IEventBus>();
eventBus.Subscribe<MessageSentEvent, MessageSentEventHandler>();

Vert.x 4 eventbus serialize multiple classes with same codec

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fun main() {
  val vertx = Vertx.vertx()
  vertx.eventBus().registerCodec(GenericCodec())

  vertx.eventBus().consumer<Foo>("test-address") {
    println(it.body())
    it.reply(Bar(), genericDeliveryOptions)
  }

  vertx.eventBus().request<String>("test-address", Foo(), genericDeliveryOptions) {
    println(it.result().body())
  }

  vertx.close()
}

data class Foo(
  val foo: String = "foo",
)

data class Bar(
  val bar: String = "bar",
)

class GenericCodec : MessageCodec<Any, Any> {
  companion object {
    const val NAME = "generic"
  }

  private val mapper: ObjectMapper = ObjectMapper()

  override fun encodeToWire(buffer: Buffer, s: Any) {
    buffer.appendBytes(mapper.writeValueAsBytes(s))
  }

  override fun decodeFromWire(pos: Int, buffer: Buffer): Any {
    throw RuntimeException("should never get here, unless using clustered mode")
  }

  override fun transform(s: Any): Any {
    return s
  }

  override fun name(): String {
    return NAME
  }

  override fun systemCodecID(): Byte {
    return -1
  }
}

val genericDeliveryOptions = deliveryOptionsOf(codecName = GenericCodec.NAME)

Using the mitt-library in Vue with Webpack hot-reload causes problems?

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// mitt.on('list_refresh', () => refresh()) ❌

mitt.on('list_refresh', refresh) ✅
mitt.off('list_refresh', refresh)

import { onMounted, onUnmounted } from 'vue'

export default {
  setup() {
    const refresh = () => { /*...*/ }

    onMounted(() => mitt.on('list_refresh', refresh))
    onUnmounted(() => mitt.off('list_refresh', refresh)) 👈
  }
}

-----------------------

// mitt.on('list_refresh', () => refresh()) ❌

mitt.on('list_refresh', refresh) ✅
mitt.off('list_refresh', refresh)

import { onMounted, onUnmounted } from 'vue'

export default {
  setup() {
    const refresh = () => { /*...*/ }

    onMounted(() => mitt.on('list_refresh', refresh))
    onUnmounted(() => mitt.off('list_refresh', refresh)) 👈
  }
}

Unable to Filter By Category in A Forum

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<v-btn text color="blue" @click="filterCategory(category.id)">{{category.name}}</v-btn>

//...

filterCategory(id) {
    EventBus.$emit('filterCategory', id);
}

computed: {
    filteredQuestions() {
        if (this.id) {
            return this.questions.filter(question => question.category_id === this.id)
        }

        return this.questions;
    }
},

listen() {
    EventBus.$on('filterCategory', (id) => { 
        this.id = id;
    })
},

<question v-for="question in filteredQuestions"

-----------------------

<v-btn text color="blue" @click="filterCategory(category.id)">{{category.name}}</v-btn>

//...

filterCategory(id) {
    EventBus.$emit('filterCategory', id);
}

computed: {
    filteredQuestions() {
        if (this.id) {
            return this.questions.filter(question => question.category_id === this.id)
        }

        return this.questions;
    }
},

listen() {
    EventBus.$on('filterCategory', (id) => { 
        this.id = id;
    })
},

<question v-for="question in filteredQuestions"

-----------------------

<v-btn text color="blue" @click="filterCategory(category.id)">{{category.name}}</v-btn>

//...

filterCategory(id) {
    EventBus.$emit('filterCategory', id);
}

computed: {
    filteredQuestions() {
        if (this.id) {
            return this.questions.filter(question => question.category_id === this.id)
        }

        return this.questions;
    }
},

listen() {
    EventBus.$on('filterCategory', (id) => { 
        this.id = id;
    })
},

<question v-for="question in filteredQuestions"

-----------------------

<v-btn text color="blue" @click="filterCategory(category.id)">{{category.name}}</v-btn>

//...

filterCategory(id) {
    EventBus.$emit('filterCategory', id);
}

computed: {
    filteredQuestions() {
        if (this.id) {
            return this.questions.filter(question => question.category_id === this.id)
        }

        return this.questions;
    }
},

listen() {
    EventBus.$on('filterCategory', (id) => { 
        this.id = id;
    })
},

<question v-for="question in filteredQuestions"

See all related Code Snippets

Community Discussions

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NuxtJS and event bus
How do I implement a Logout functionality from a React Router Link to imports an array?
How can I change this Navbar dropdown item to update from "Login" to "Logout" when a user logs in?
only one child route displaying in react? displays component for a different route instead of its own
EventBus implementation using Coroutines and LiveData
Generic Method in Java with out parameters
How can I configure my event bus in ASP.NET Core 6 - Migration to .NET 6

Trending Discussions on EventBus

QUESTION

How can I redirect a user to login when a certain link is clicked using JWT

Asked 2022-Apr-08 at 08:49

I am trying to make it so that when a user clicks on a certain Link (Upload Component), it will redirect them to to the login component and am not sure how to accomplish this task in React. I was directed to another answered question, but it hasn't helped me as I am still confused on what I need to do with my own set up. I understand I need to make my own protected route (maybe), but I saw others accessing useContext and I do not have any file with context. I am using Version 6 in react dom. I am also using React router and redux in my project so I know I need to access the state somehow, just not sure how to wrap my mind around it so if anyone could help, I would appreciate it. The user is being stored in local storage with JWT authentication.

App.js:

import React, {useState, useEffect, useCallback} from 'react';
import {useDispatch, useSelector} from 'react-redux';
import {BrowserRouter as Router, Routes, Route} from 'react-router-dom'; //Switch was replaced by Routes in react-router-dom v6
import './App.css';
import Navbar from './components/Navbar';
import Footer from './components/Footer';
import Home from './components/pages/Home';
import Uploads from './components/pages/Uploads';
import Account from './components/pages/Account';
import Login from './components/pages/Login';
import LogOut from './components/Logout';
import Register from './components/pages/Register';
import Profile from './components/pages/Profile';
import EditProfile from './components/pages/EditProfile';
import BoardAdmin from './components/pages/BoardAdmin';
import BoardModerator from './components/pages/BoardModerator';
import BoardUser from './components/pages/BoardUser';
import {logout} from './slices/auth';
import EventBus from './common/EventBus';

const App = () => {
    const [showModeratorBoard, setShowModeratorBoard] = useState(false);
    const [showAdminBoard, setShowAdminBoard] = useState(false);
    const {user: currentUser} = useSelector((state) => state.auth);
    const dispatch = useDispatch();

    useEffect(() => {
        if (currentUser) {
            setShowModeratorBoard(currentUser.roles.includes('ROLE_MODERATOR'));
            setShowAdminBoard(currentUser.roles.includes('ROLE_ADMIN'));
        } else {
            setShowModeratorBoard(false);
            setShowAdminBoard(false);
        }
    }, [currentUser]);

    return (
        <>
            <Router>
                <Navbar />
                <Routes>
                    <Route path='/' element={<Home />} />
                    <Route path='/create/upload' element={<Uploads />} />
                    <Route path='/my-account' element={<Account />} />
                    <Route path='/login' element={<Login />} />
                    <Route path='/logout' element={<LogOut />} />
                    <Route path='/register' element={<Register />} />
                    <Route path='/profile' element={<Profile />} />
                    <Route path='/profile/edit' element={<EditProfile />} />
                    <Route path='/user' element={<BoardUser />} />
                    <Route path='/mod' element={<BoardModerator />} />
                    <Route path='/admin' element={<BoardAdmin />} />
                </Routes>
                <Footer />
            </Router>
        </>
    );
};

export default App;

Auth.js:

import {createSlice, createAsyncThunk} from '@reduxjs/toolkit';
import {setMessage} from './messages';
import AuthService from '../services/auth.service';
const user = JSON.parse(localStorage.getItem('user'));
export const register = createAsyncThunk(
    'auth/register',
    async ({username, email, password}, thunkAPI) => {
        try {
            const response = await AuthService.register(username, email, password);
            thunkAPI.dispatch(setMessage(response.data.message));
            return response.data;
        } catch (error) {
            const message =
                (error.response &&
                    error.response.data &&
                    error.response.data.message) ||
                error.message ||
                error.toString();
            thunkAPI.dispatch(setMessage(message));
            return thunkAPI.rejectWithValue();
        }
    }
);
export const login = createAsyncThunk(
    'auth/login',
    async ({username, password}, thunkAPI) => {
        try {
            const data = await AuthService.login(username, password);
            return {user: data};
        } catch (error) {
            const message =
                (error.response &&
                    error.response.data &&
                    error.response.data.message) ||
                error.message ||
                error.toString();
            thunkAPI.dispatch(setMessage(message));
            return thunkAPI.rejectWithValue();
        }
    }
);
export const logout = createAsyncThunk('auth/logout', async () => {
    await AuthService.logout();
});
const initialState = user
    ? {isLoggedIn: true, user}
    : {isLoggedIn: false, user: null};
const authSlice = createSlice({
    name: 'auth',
    initialState,
    extraReducers: {
        [register.fulfilled]: (state, action) => {
            state.isLoggedIn = false;
        },
        [register.rejected]: (state, action) => {
            state.isLoggedIn = false;
        },
        [login.fulfilled]: (state, action) => {
            state.isLoggedIn = true;
            state.user = action.payload.user;
        },
        [login.rejected]: (state, action) => {
            state.isLoggedIn = false;
            state.user = null;
        },
        [logout.fulfilled]: (state, action) => {
            state.isLoggedIn = false;
            state.user = null;
        },
    },
});
const {reducer} = authSlice;
export default reducer;

It looks like adding the if statement in my upload file is making it so that a logged in user can access the h1 element that is in the file, but not an unauthenticated user. So its working to an extent, just not redirecting back to login.

Upload.jsx:

import React from 'react';
import {Link} from 'react-router-dom';
import {useSelector} from 'react-redux';
function Uploads() {
    const {user: currentUser} = useSelector((state) => state.auth);
    if (!currentUser) {
        return <Link to='/login' />;
    }
    return (
        <>
            <h1 className='page'>UPLOADS</h1>
        </>
    );
}

export default Uploads;

ANSWER

Answered 2022-Apr-08 at 08:49

Rendering the Link doesn't imperatively navigate, use the Navigation component.

Example:

import React, { useEffect } from 'react';
import { Navigate } from 'react-router-dom';
import { useSelector } from 'react-redux';

function Uploads() {
  const { user: currentUser } = useSelector((state) => state.auth);

  if (!currentUser) {
    return <Navigate to='/login' replace />;
  }
  return (
    <>
      <h1 className='page'>UPLOADS</h1>
    </>
  );
}

export default Uploads;

Typically you would protect the route instead. If you wanted to do that:

import { Navigate, Outlet } from 'react-router-dom';
import { useSelector } from 'react-redux';

const PrivateRoutes = () => {
  const { user: currentUser } = useSelector((state) => state.auth);
  return currentUser 
    ? <Outlet />
    : <Navigate to="/login" replace />;
}

...

<Routes>
  <Route path='/' element={<Home />} />
  <Route element={<PrivateRoutes />}>
    <Route path='/create/upload' element={<Uploads />} />
    ... any other protected routes ...
  </Route>
  ... other unprotected routes ...
</Routes>

Source https://stackoverflow.com/questions/71793361

QUESTION

Every bean/class instance created twice in spring boot application

Asked 2022-Apr-08 at 06:46

I'm using java based configuration, using only @Component and @Scheduler Annotation in my other classes, but I don't know why all classes in class path loaded twice. How to prevent this and how to debug it? problem : All my scheduled methods are running twice in scheduled interval. @Scheduled(cron = "0 0/5 * * * ?")

    @EnableScheduling
    @SpringBootApplication
    @ComponentScan(basePackages = "com.example")
    public class Dashboard implements CommandLineRunner{
    
    
        @Autowired
        private ApplicationContext appContext;
    
        @Autowired
        private EventBus eventBus;
    
        @Auditable(eventProvider = EventProvider.class)
        @PostConstruct
        public void startupApplication() {
            try {
                EventProvider provider = appContext.getBean(EventProvider.class);
                AuditRequestContext requestContext = new AuditRequestContext(null, null, null, null);
                Event aaaEvent = provider.getEvent(requestContext);
                eventBus.post(aaaEvent);
            } catch (Exception e) {
                System.out.println("Error getting bean for the class: " , e);
            }
        }
    
        public static void main(String[] args) {
            SpringApplication.run(Dashboard.class, args);
        }
    
        @Override
        public void run(String... args) throws Exception {
           String [] beans = appContext.getBeanDefinitionNames();
           Arrays.sort(beans);
           for(String bean : beans) {
               logger.info("bean :: " + bean);
           }  
        }
    
    }

Log printed: every bean loaded twice (All my scheduled methods are running twice)

dashboard [INFO ] 23034 2022-04-08 04:54:05.227 [main] LoggerService - bean :: auditConfig 
dashboard [INFO ] 23034 2022-04-08 04:54:05.227 [main] LoggerService - bean :: auditConfig 
dashboard [INFO ] 23034 2022-04-08 04:54:05.227 [main] LoggerService - bean :: auditRequestBodyAdviceAdapter 
dashboard [INFO ] 23034 2022-04-08 04:54:05.227 [main] LoggerService - bean :: auditRequestBodyAdviceAdapter 
dashboard [INFO ] 23034 2022-04-08 04:54:05.227 [main] LoggerService - bean :: auditRequestInterceptor
dashboard [INFO ] 23034 2022-04-08 04:54:05.227 [main] LoggerService - bean :: auditRequestInterceptor 
dashboard [INFO ] 23034 2022-04-08 04:54:05.227 [main] LoggerService - bean :: authEntryPoint 
dashboard [INFO ] 23034 2022-04-08 04:54:05.227 [main] LoggerService - bean :: authEntryPoint 
dashboard [INFO ] 23034 2022-04-08 04:54:05.227 [main] LoggerService - bean :: authFilter 
dashboard [INFO ] 23034 2022-04-08 04:54:05.227 [main] LoggerService - bean :: authFilter 
dashboard [INFO ] 23034 2022-04-08 04:54:05.227 [main] LoggerService - bean :: authenticationController 
dashboard [INFO ] 23034 2022-04-08 04:54:05.227 [main] LoggerService - bean :: authenticationController

How to resolve this?

Added Log4j configuration.

<?xml version="1.0" encoding="UTF-8"?>
<Configuration monitorInterval="60">
    <Properties>
        <Property name="basePath">${example.log.path}</Property>
        <Property name="host">localhost</Property>
        <Property name="port">514</Property>
        <Property name="appName">example Dashboard</Property>
        <Property name="facility">local0</Property>
        <Property name="mdcId">example Dashboard</Property>
    </Properties>
    <Appenders>
        <File name="fileLogger" fileName="${basePath}/${example.log.name}">
            <PatternLayout>
                <pattern>${package.name} [%-5level] %5X{pid} %d{yyyy-MM-dd HH:mm:ss.SSS} [%t] %c{1} - %msg%n
                </pattern>
            </PatternLayout>
        </File>
        <Syslog name="syslog"
                format="RFC5424" host="${host}" port="${port}"
                protocol="UDP" appName="${appName}" includeMDC="true"
                facility="${facility}" enterpriseNumber="18060" newLine="true"
                mdcId="${mdcId}">
        </Syslog>
    </Appenders>
    <Loggers>
        <Logger name="com.example" level="info" additivity="true">
            <AppenderRef ref="fileLogger"/>
            <AppenderRef ref="syslog"/>
        </Logger>
        <Root level="info">
            <AppenderRef ref="fileLogger"/>
        </Root>
    </Loggers>
</Configuration>

ANSWER

Answered 2022-Apr-08 at 06:46

You want to set additivity to false for your com.example logger. @AndyWilkinson is correct you're duplicating your logs, not your beans.

Source https://stackoverflow.com/questions/71792008

QUESTION

How do I implement a Logout functionality from a React Router Link to imports an array?

Asked 2022-Mar-16 at 22:49

I am trying to implement a logout functionality and am not sure what I need to do to implement it with my current set up. I was able to set up a Login functionality that pulls the correct profile data and once logged in, the Navbar + Dropdown Items are updated to display a link to logout. However, I am unsure of how I can add the logout functionality at the moment. I have been following guides but am stuck since nothing I am trying is working, once I hit a the logout link it links to /logout but fails to actually logout. The tutorial I am following claims I can do it via the frontend (I am using JWT).

Navbar.jsx:

import React, {useState, useEffect} from 'react';
import {Link} from 'react-router-dom'; 
import './Navbar.css';
import Dropdown from './Dropdown';
import {NavItemsList} from './NavItemsList';
import NavItems from './NavItems';

function Navbar() {
    const [click, setClick] = useState(false); 
    const [button, setButton] = useState(true);
    const [dropdown, setDropdown] = useState(false);

    const handleClick = () => setClick(!click);
    const closeMobileMenu = () => setClick(false);

    const onMouseEnter = () => {
        if (window.innerWidth < 960) {
            setDropdown(false);
        } else {
            setDropdown(true);
        }
    };

    const onMouseLeave = () => {
        if (window.innerWidth < 960) {
            setDropdown(false);
        } else {
            setDropdown(false);
        }
    };

    return (
        <>
            <nav className='navbar'>
                <div className='navbar-container-whole'>
                    <div className='left-nav-container'>
                        {/* Link in react-router-dom essentially replaces a tag.*/}
                        <Link to='/' className='navbar-logo'>
                            <img src='/images/logo.png' className='hashtek-logo' alt='logo' />
                            <h1 className='navbar-name'>HashTek</h1>
                        </Link>
                    </div>
                    {/* .navbar-container will create a div with that class name. */}
                    <div className='center-nav-container'>
                        <form action='./' method='get' id='search-form'>
                            <div class='searchbar'>
                                <input
                                    class='searchbar_input'
                                    type='search'
                                    name='search'
                                    placeholder='Search..'
                                />

                                <button type='submit' class='searchbar_button'>
                                    <i class='material-icons'>search</i>
                                </button>
                            </div>
                        </form>
                    </div>
                    <div className='right-nav-container'>
                        <ul className={click ? 'nav-menu active' : 'nav-menu'}>
                            <div className='text-links'>
                                {/* This line above is for when you are on mobile, and an item is clicked, the nav menu will disappear */}
                                {NavItemsList.slice(0, 4).map((menu, index) => {
                                    return <NavItems items={menu} key={index} />;
                                })}
                            </div>
                            <div className='logo-links'>
                                {NavItemsList.slice(4, 6).map((menu, index) => {
                                    return <NavItems items={menu} key={index} />;
                                })}
                            </div>
                        </ul>
                        <div className='menu-icon' onClick={handleClick}>
                            <i className={click ? 'fas fa-times' : 'fas fa-bars'} />
                        </div>
                    </div>
                </div>
            </nav>
        </>
    );
}

export default Navbar;

NavItemList.js:

export const NavItemsList = [{
        title: 'Products',
        path: '/products',
        cName: 'nav-links',
    },
    {
        title: 'Stats',
        path: '/stats',
        cName: 'nav-links',
    },
    {
        title: 'Contacts',
        path: '/contacts',
        cName: 'nav-links',
        subNav: [{
                title: 'About',
                path: '/contacts/about',
                cName: 'dropdown-link',
                menuName: 'contacts-menu',
            },
            {
                title: 'How To',
                path: '/contacts/how-to',
                cName: 'dropdown-link',
                menuName: 'contacts-menu',
            },
            {
                title: 'Developers',
                path: '/contacts/developers',
                cName: 'dropdown-link',
                menuName: 'contacts-menu',
            },
            {
                title: 'Designers',
                path: '/contacts/designers',
                cName: 'dropdown-link',
                menuName: 'contacts-menu',
            },
            {
                title: 'Mentors',
                path: '/contacts/mentors',
                cName: 'dropdown-link',
                menuName: 'contacts-menu',
            },
        ],
    },
    {
        title: 'Services',
        path: '/services',
        cName: 'nav-links',
        subNav: [{
                title: 'Streaming',
                path: '/services/streaming',
                cName: 'dropdown-link',
                menuName: 'services-menu',
            },
            {
                title: 'Editing',
                path: '/services/editing',
                cName: 'dropdown-link',
                menuName: 'services-menu',
            },
        ],
    },
    {
        title: Account,
        path: '/my-account',
        cName: 'nav-links',
        subNav: [{
                title: 'Login',
                path: '/login',
                cName: 'dropdown-link',
                menuName: 'account-menu',
                authenticated: false,
            },
            {
                title: 'Logout',
                path: '/logout',
                cName: 'dropdown-link',
                menuName: 'account-menu',
                authenticated: true,
            },
            {
                title: 'Profile',
                path: '/profile',
                cName: 'dropdown-link',
                menuName: 'account-menu',
            },
        ],
    },
    {
        title: Help,
        path: '/help',
        cName: 'nav-links',
    },
];

import React, {useState, useEffect} from 'react';
import {useDispatch, useSelector} from 'react-redux';
import {Link} from 'react-router-dom';
import {Formik, Field, Form, ErrorMessage} from 'formik';
import * as Yup from 'yup';
import {login} from '../../slices/auth';
import {clearMessage} from '../../slices/messages';
const Login = (props) => {
    const [loading, setLoading] = useState(false);
    const {isLoggedIn} = useSelector((state) => state.auth);
    const {message} = useSelector((state) => state.message);
    const dispatch = useDispatch();
    useEffect(() => {
        dispatch(clearMessage());
    }, [dispatch]);
    const initialValues = {
        username: '',
        password: '',
    };
    const validationSchema = Yup.object().shape({
        username: Yup.string().required('This field is required!'),
        password: Yup.string().required('This field is required!'),
    });
    const handleLogin = (formValue) => {
        const {username, password} = formValue;
        setLoading(true);
        dispatch(login({username, password}))
            .unwrap()
            .then(() => {
                props.history.push('/profile');
                window.location.reload();
            })
            .catch(() => {
                setLoading(false);
            });
    };
    if (isLoggedIn) {
        return <Link to='/profile' />;
    }
    return (
        <div className='login-form'>
            <div className='card card-container'>
                <Formik
                    initialValues={initialValues}
                    validationSchema={validationSchema}
                    onSubmit={handleLogin}
                >
                    <Form>
                        <div className='form-group'>
                            <label htmlFor='username'>Username</label>
                            <Field name='username' type='text' className='form-control' />
                            <ErrorMessage
                                name='username'
                                component='div'
                                className='alert alert-danger'
                            />
                        </div>
                        <div className='form-group'>
                            <label htmlFor='password'>Password</label>
                            <Field name='password' type='password' className='form-control' />
                            <ErrorMessage
                                name='password'
                                component='div'
                                className='alert alert-danger'
                            />
                        </div>
                        <div className='form-group'>
                            <button
                                type='submit'
                                className='btn btn-primary btn-block'
                                disabled={loading}
                            >
                                {loading && (
                                    <span className='spinner-border spinner-border-sm'></span>
                                )}
                                <span>Login</span>
                            </button>
                        </div>
                    </Form>
                </Formik>
            </div>
            {message && (
                <div className='form-group'>
                    <div className='alert alert-danger' role='alert'>
                        {message}
                    </div>
                </div>
            )}
        </div>
    );
};
export default Login;

auth.service.js:

//Authentication Service file. This service uses Axios for HTTP requests and Local Storage for user information & JWT.
// It provides following important functions:

// register(): POST {username, email, password}
// login(): POST {username, password} & save JWT to Local Storage
// logout(): remove JWT from Local Storage

import axios from 'axios';
const API_URL = 'http://localhost:8080/api/auth/';
const register = (username, email, password) => {
    return axios.post(API_URL + 'signup', {
        username,
        email,
        password,
    });
};
const login = (username, password) => {
    return axios
        .post(API_URL + 'login', {
            username,
            password,
        })
        .then((response) => {
            if (response.data.accessToken) {
                localStorage.setItem('user', JSON.stringify(response.data));
            }
            return response.data;
        });
};
const logout = () => {
    localStorage.removeItem('user');
};
const authService = {
    register,
    login,
    logout,
};
export default authService;

auth.js:

// We’re gonna import AuthService to make asynchronous HTTP requests with trigger one or more dispatch in the result.

// – register(): calls the AuthService.register(username, email, password) & dispatch setMessage if successful/failed
// – login(): calls the AuthService.login(username, password) & dispatch setMessage if successful/failed
// – logout(): calls the AuthService.logout().

// setMessage is imported from message slice that we’ve created above.
// We also need to use Redux Toolkit createAsyncThunk which provides a thunk that will take care of the action types and dispatching the right actions based on the returned promise.
//There are 3 async Thunks to be exported:

// register
// login
// logout

import {createSlice, createAsyncThunk} from '@reduxjs/toolkit';
import {setMessage} from './messages';
import AuthService from '../services/auth.service';
const user = JSON.parse(localStorage.getItem('user'));
export const register = createAsyncThunk(
    'auth/register',
    async ({username, email, password}, thunkAPI) => {
        try {
            const response = await AuthService.register(username, email, password);
            thunkAPI.dispatch(setMessage(response.data.message));
            return response.data;
        } catch (error) {
            const message =
                (error.response &&
                    error.response.data &&
                    error.response.data.message) ||
                error.message ||
                error.toString();
            thunkAPI.dispatch(setMessage(message));
            return thunkAPI.rejectWithValue();
        }
    }
);
export const login = createAsyncThunk(
    'auth/login',
    async ({username, password}, thunkAPI) => {
        try {
            const data = await AuthService.login(username, password);
            return {user: data};
        } catch (error) {
            const message =
                (error.response &&
                    error.response.data &&
                    error.response.data.message) ||
                error.message ||
                error.toString();
            thunkAPI.dispatch(setMessage(message));
            return thunkAPI.rejectWithValue();
        }
    }
);
export const logout = createAsyncThunk('auth/logout', async () => {
    await AuthService.logout();
});
const initialState = user
    ? {isLoggedIn: true, user}
    : {isLoggedIn: false, user: null};
const authSlice = createSlice({
    name: 'auth',
    initialState,
    extraReducers: {
        [register.fulfilled]: (state, action) => {
            state.isLoggedIn = false;
        },
        [register.rejected]: (state, action) => {
            state.isLoggedIn = false;
        },
        [login.fulfilled]: (state, action) => {
            state.isLoggedIn = true;
            state.user = action.payload.user;
        },
        [login.rejected]: (state, action) => {
            state.isLoggedIn = false;
            state.user = null;
        },
        [logout.fulfilled]: (state, action) => {
            state.isLoggedIn = false;
            state.user = null;
        },
    },
});
const {reducer} = authSlice;
export default reducer;

App.js:

import React, {useState, useEffect, useCallback} from 'react';
import {useDispatch, useSelector} from 'react-redux';
import {BrowserRouter as Router, Routes, Route} from 'react-router-dom'; //Switch was replaced by Routes in react-router-dom v6
import './App.css';
import Navbar from './components/Navbar';
import Footer from './components/Footer';
import Home from './components/pages/Home';
import Account from './components/pages/Account';
import Login from './components/pages/Login';
import Profile from './components/pages/Profile';

import {logout} from './slices/auth';
import EventBus from './common/EventBus';

const App = () => {
    const {user: currentUser} = useSelector((state) => state.auth);
    const dispatch = useDispatch();
    const logOut = useCallback(() => {
        dispatch(logout());
    }, [dispatch]);
    useEffect(() => {
        EventBus.on('logout', () => {
            logOut();
        });
        return () => {
            EventBus.remove('logout');
        };
    }, [currentUser, logOut]);
    return (
        <>
            <Router>
                <Navbar />
                <Routes>
                    <Route path='/' element={<Home />} />
                    <Route path='/my-account' element={<Account />} />
                    <Route path='/login' element={<Login />} />
                    {currentUser ? (
                        <Route path='/logout' onClick={logOut} />
                    ) : ( //Did something wrong here I believe. Not sure if I need to include this in another file.
                        <Route path='/login' element={<Login />} />
                    )}
                    <Route path='/profile' element={<Profile />} />
                </Routes>
                <Footer />
            </Router>
        </>
    );
};

export default App;

I feel like I am close, just missing something or have something in the wrong place. If anyone can help me, I would deeply appreciate it. Sorry if I included too much code, just want everyone to have a good idea of whats going on. Thank you!

ANSWER

Answered 2022-Mar-16 at 22:46

It seems you only need a Logout component that dispatches the logout action when it mounts, waits for the action to complete, and likely redirect back to a homepage or similar.

Example:

const Logout = () => {
  const dispatch = useDispatch();
  const navigate = useNavigate();

  useEffect(() => {
    dispatch(logout())
      .then(() => {
        navigate("/", { replace: true });
      });

  }, []);

  return <LoadingSpinner />;
};

App

There likely also isn't a string need to conditionally render the routes, just render them normally.

...
import Login from './components/pages/Login';
import Logout from './components/pages/Logout';
...

...

<Router>
  <Navbar />
  <Routes>
    <Route path='/' element={<Home />} />
    <Route path='/my-account' element={<Account />} />
    <Route path='/login' element={<Login />} />
    <Route path='/logout' element={<LogOut />} />
    <Route path='/profile' element={<Profile />} />
  </Routes>
  <Footer />
</Router>

Source https://stackoverflow.com/questions/71504920

QUESTION

How can I change this Navbar dropdown item to update from "Login" to "Logout" when a user logs in?

Asked 2022-Mar-16 at 08:47

I am trying to update my Navbar component so that when a user logs in, the navbar dropdown item "Login" changes to "Logout" but I am having issues. I am new to react and JS but learning as I go, so I apologize for any confusion in this question. I have jsx components for my Navbar, Dropdown, Footer, and for each page that a user wants to view which is rendered in my App.js file.

Navbar.jsx:

import React, {useState, useEffect} from 'react';
import {Link} from 'react-router-dom'; 
import './Navbar.css';
import Dropdown from './Dropdown';
import {NavItemsList} from './NavItemsList';
import NavItems from './NavItems';

function Navbar() {
    const [click, setClick] = useState(false); 
    const [button, setButton] = useState(true);
    const [dropdown, setDropdown] = useState(false);

    const handleClick = () => setClick(!click);
    const closeMobileMenu = () => setClick(false);

    const onMouseEnter = () => {
        if (window.innerWidth < 960) {
            setDropdown(false);
        } else {
            setDropdown(true);
        }
    };

    const onMouseLeave = () => {
        if (window.innerWidth < 960) {
            setDropdown(false);
        } else {
            setDropdown(false);
        }
    };

    return (
        <>
            <nav className='navbar'>
                <div className='navbar-container-whole'>
                    <div className='left-nav-container'>
                        {/* Link in react-router-dom essentially replaces a tag.*/}
                        <Link to='/' className='navbar-logo'>
                            <img src='/images/logo.png' className='hashtek-logo' alt='logo' />
                            <h1 className='navbar-name'>HashTek</h1>
                        </Link>
                    </div>
                    {/* .navbar-container will create a div with that class name. */}
                    <div className='center-nav-container'>
                        <form action='./' method='get' id='search-form'>
                            <div class='searchbar'>
                                <input
                                    class='searchbar_input'
                                    type='search'
                                    name='search'
                                    placeholder='Search..'
                                />

                                <button type='submit' class='searchbar_button'>
                                    <i class='material-icons'>search</i>
                                </button>
                            </div>
                        </form>
                    </div>
                    <div className='right-nav-container'>
                        <ul className={click ? 'nav-menu active' : 'nav-menu'}>
                            <div className='text-links'>
                                {/* This line above is for when you are on mobile, and an item is clicked, the nav menu will disappear */}
                                {NavItemsList.slice(0, 4).map((menu, index) => {
                                    return <NavItems items={menu} key={index} />;
                                })}
                            </div>
                            <div className='logo-links'>
                                {NavItemsList.slice(4, 6).map((menu, index) => {
                                    return <NavItems items={menu} key={index} />;
                                })}
                            </div>
                        </ul>
                        <div className='menu-icon' onClick={handleClick}>
                            <i className={click ? 'fas fa-times' : 'fas fa-bars'} />
                        </div>
                    </div>
                </div>
            </nav>
        </>
    );
}

export default Navbar;

NavItemsList.js:

export const NavItemsList = [
    {
        title: 'Products',
        path: '/products',
        cName: 'nav-links',
    },
    {
        title: 'Stats',
        path: '/stats',
        cName: 'nav-links',
    },
    {
        title: 'Contacts',
        path: '/contacts',
        cName: 'nav-links',
        subNav: [
            {
                title: 'About',
                path: '/contacts/about',
                cName: 'dropdown-link',
                menuName: 'contacts-menu',
            },
            {
                title: 'How To',
                path: '/contacts/how-to',
                cName: 'dropdown-link',
                menuName: 'contacts-menu',
            },
            {
                title: 'Developers',
                path: '/contacts/developers',
                cName: 'dropdown-link',
                menuName: 'contacts-menu',
            },
            {
                title: 'Designers',
                path: '/contacts/designers',
                cName: 'dropdown-link',
                menuName: 'contacts-menu',
            },
            {
                title: 'Mentors',
                path: '/contacts/mentors',
                cName: 'dropdown-link',
                menuName: 'contacts-menu',
            },
        ],
    },
    {
        title: 'Services',
        path: '/services',
        cName: 'nav-links',
        subNav: [
            {
                title: 'Streaming',
                path: '/services/streaming',
                cName: 'dropdown-link',
                menuName: 'services-menu',
            },
            {
                title: 'Editing',
                path: '/services/editing',
                cName: 'dropdown-link',
                menuName: 'services-menu',
            },
        ],
    },
    {
        title: Account,
        path: '/my-account',
        cName: 'nav-links',
        subNav: [
            {
                title: 'Login',
                path: '/login',
                cName: 'dropdown-link',
                menuName: 'account-menu',
            },
            {
                title: 'Profile',
                path: '/profile',
                cName: 'dropdown-link',
                menuName: 'account-menu',
            },
        ],
    },
    {
        title: Help,
        path: '/help',
        cName: 'nav-links',
    },
];

Dropdown.jsx:

import React, {useState} from 'react';
import {Link} from 'react-router-dom';
import './Dropdown.css';

function Dropdown(props) {
    const [click, setClick] = useState(false);
    const handleClick = () => setClick(!click);
    const submenus = props.submenus;

    return (
        <ul
            onClick={handleClick}
            className={click ? 'dropdown-menu clicked' : 'dropdown-menu'}
        >
            {submenus.map((subNav, index) => (
                <div className={subNav.menuName}>
                    <li key={index} className='dropdown-links'>
                        <Link
                            className={subNav.cName}
                            to={subNav.path}
                            onClick={() => setClick(false)}
                        >
                            {subNav.title}
                        </Link>
                    </li>
                </div>
            ))}
        </ul>
    );
}

export default Dropdown;

NavItems.jsx:

import React, {useState} from 'react';
import Dropdown from './Dropdown';
import {Link} from 'react-router-dom';

function NavItems(props) {
    const items = props.items;
    const [click, setClick] = useState(false);
    const handleClick = () => setClick(!click);
    const [dropdown, setDropdown] = useState(false);

    const onMouseEnter = () => {
        if (window.innerWidth < 960) {
            setDropdown(false);
        } else {
            setDropdown(true);
        }
    };

    const onMouseLeave = () => {
        if (window.innerWidth < 960) {
            setDropdown(false);
        } else {
            setDropdown(false);
        }
    };

    return (
        <div className='link-container' onMouseLeave={onMouseLeave}>
            <li className='nav-item'>
                {items.subNav ? (
                    <>
                        <Link
                            className={items.cName}
                            to={items.path}
                            onClick={() => setClick(false)}
                            onMouseEnter={onMouseEnter}
                        >
                            {items.title}
                        </Link>

                        {dropdown && <Dropdown submenus={items.subNav} />}
                    </>
                ) : (
                    <Link
                        className={items.cName}
                        to={items.path}
                        onClick={() => setClick(false)}
                    >
                        {items.title}
                    </Link>
                )}
            </li>
        </div>
    );
}

export default NavItems;

I am following a tutorial that implements the navbar in their App.js file as follows:

import React, { useState, useEffect, useCallback } from "react";
import { useDispatch, useSelector } from "react-redux";
import { BrowserRouter as Router, Switch, Route, Link } from "react-router-dom";
import "bootstrap/dist/css/bootstrap.min.css";
import "./App.css";
import Login from "./components/Login";
import Register from "./components/Register";
import Home from "./components/Home";
import Profile from "./components/Profile";
import BoardUser from "./components/BoardUser";
import BoardModerator from "./components/BoardModerator";
import BoardAdmin from "./components/BoardAdmin";
import { logout } from "./slices/auth";
import EventBus from "./common/EventBus";
const App = () => {
  const [showModeratorBoard, setShowModeratorBoard] = useState(false);
  const [showAdminBoard, setShowAdminBoard] = useState(false);
  const { user: currentUser } = useSelector((state) => state.auth);
  const dispatch = useDispatch();
  const logOut = useCallback(() => {
    dispatch(logout());
  }, [dispatch]);
  useEffect(() => {
    if (currentUser) {
      setShowModeratorBoard(currentUser.roles.includes("ROLE_MODERATOR"));
      setShowAdminBoard(currentUser.roles.includes("ROLE_ADMIN"));
    } else {
      setShowModeratorBoard(false);
      setShowAdminBoard(false);
    }
    EventBus.on("logout", () => {
      logOut();
    });
    return () => {
      EventBus.remove("logout");
    };
  }, [currentUser, logOut]);
  return (
    <Router>
      <div>
        <nav className="navbar navbar-expand navbar-dark bg-dark">
          <Link to={"/"} className="navbar-brand">
            bezKoder
          </Link>
          <div className="navbar-nav mr-auto">
            <li className="nav-item">
              <Link to={"/home"} className="nav-link">
                Home
              </Link>
            </li>
            {showModeratorBoard && (
              <li className="nav-item">
                <Link to={"/mod"} className="nav-link">
                  Moderator Board
                </Link>
              </li>
            )}
            {showAdminBoard && (
              <li className="nav-item">
                <Link to={"/admin"} className="nav-link">
                  Admin Board
                </Link>
              </li>
            )}
            {currentUser && (
              <li className="nav-item">
                <Link to={"/user"} className="nav-link">
                  User
                </Link>
              </li>
            )}
          </div>
          {currentUser ? (
            <div className="navbar-nav ml-auto">
              <li className="nav-item">
                <Link to={"/profile"} className="nav-link">
                  {currentUser.username}
                </Link>
              </li>
              <li className="nav-item">
                //INTERESTED IN THIS
                <a href="/login" className="nav-link" onClick={logOut}> 
                </a>
              </li>
            </div>
          ) : (
            <div className="navbar-nav ml-auto">
              <li className="nav-item">
                <Link to={"/login"} className="nav-link">
                  Login
                </Link>
              </li>
              <li className="nav-item">
                <Link to={"/register"} className="nav-link">
                  Sign Up
                </Link>
              </li>
            </div>
          )}
        </nav>
        <div className="container mt-3">
          <Switch>
            <Route exact path={["/", "/home"]} component={Home} />
            <Route exact path="/login" component={Login} />
            <Route exact path="/register" component={Register} />
            <Route exact path="/profile" component={Profile} />
            <Route path="/user" component={BoardUser} />
            <Route path="/mod" component={BoardModerator} />
            <Route path="/admin" component={BoardAdmin} />
          </Switch>
        </div>
      </div>
    </Router>
  );
};
export default App;

From what I can tell, they are checking the state of the currentUser and if there is one, then the Navbar will be updated to display LogOut and the current user's username. This is where I am having trouble, since I have decided to import an array into my Navbar instead. Do I need to change my Navbar so that it renders the items in the Navbar component directly without the use of the NavItemsList, or is there a way for me to check the state and change "Login" to "Logout" without changing my NavItemsList component too much? Any help would be appreciated, I have been scratching my head on how to go about this without refactoring my hard work.

ANSWER

Answered 2022-Mar-16 at 07:51

I would Ideally do something like this in the NavItem

{subNav.title==='Login'?(userLoggedIn?'Logout':'Login'):subNav.title}

Source https://stackoverflow.com/questions/71493107

QUESTION

only one child route displaying in react? displays component for a different route instead of its own

Asked 2022-Mar-12 at 23:47

When the user goes to the url for "/films/:title" it displays MovieDetailContainer which is the component for the path above it and doesnt display its own component. When I flip around the order of the urls the reverse happens. Why is this? I assume its a nesting error but I cant seem to figure it out.

here is code for the routes and the code for the full App/js is below just incase.

  <div className="container mt-3">
        <Switch>
          <Route exact path={["/", "/home"]} component={Home} />
          <Route exact path="/login" component={Login} />
          <Route exact path="/register" component={Register} />
          <Route exact path="/profile" component={Profile} />
          **<Route exact path="/films/:id" children={<MovieDetailContainer/>}/>
          <Route exact path="/films/:title" children={<MovieListComponent/>}/>**
          <Route path="/user" component={BoardUser} />
          <Route path="/creator" component={BoardCreator} />
          <Route path="/admin" component={BoardAdmin} />
        </Switch>
      </div>

import "bootstrap/dist/css/bootstrap.min.css";
import React, { useEffect, useState } from "react";
import { Link, Route, Switch } from "react-router-dom";
import styled from "styled-components";
import { useLocation } from 'react-router-dom';
// components
import Search from './components/search/Search'
import "./App.css";
// import AuthVerify from "./common/auth-verify";
import EventBus from "./common/EventBus";
import BoardAdmin from "./components/board-admin.component";
import BoardCreator from "./components/board-creator.component";
import BoardUser from "./components/board-user.component";
import Home from "./components/home.component";
import Login from "./components/login.component";
import MovieListComponent from "./components/films/movie-list.component";
import Profile from "./components/profile.component";
import Register from "./components/register.component";
import AuthService from "./services/auth.service";
import MovieInfoComponent from "./components/films/movie-info.component";
import MovieItem from "./components/films/movie-item.component";
import MovieDetailContainer from "./components/films/movie-detail-container.component"


const MovieListContainer = styled.div`
  display: flex;
  flex-direction: row;
  flex-wrap: wrap;
  padding: 30px;
  gap: 25px;
  justify-content: space-evenly; ;
`;

const App = () => {
  const [showCreatorBoard, setShowCreatorBoard] = useState(false);
  const [showAdminBoard, setShowAdminBoard] = useState(false);
  const [currentUser, setCurrentUser] = useState(undefined);
  const [locationState, setLocationState] = useState('')

  const location = useLocation();


  useEffect(() => {
    const user = AuthService.getCurrentUser();
    setLocationState(location.pathname)
    if (user) {
      setCurrentUser(user);
      setShowAdminBoard(user.roles.includes("ROLE_MODERATOR"));
      setShowAdminBoard(user.roles.includes("ROLE_ADMIN"));
    }

    EventBus.on("logout", () => {
      this.logOut();
    });

    return () => {
      EventBus.remove("logout");
    };
  }, []);
  const logOut = () => {
    AuthService.logout();
    setShowCreatorBoard(false);
    setShowAdminBoard(false);
    setCurrentUser(undefined);
  };

  return (
    <div>
      <nav className="navbar navbar-expand navbar-dark bg-dark">
        <Link to={"/"} className="navbar-brand">
          Movie App
        </Link>
        <div className="navbar-nav mr-auto">
          <li className="nav-item">
            <Link to={"/home"} className="nav-link">
              Home
            </Link>
          </li>

          {showCreatorBoard && (
            <li className="nav-item">
              <Link to={"/mod"} className="nav-link">
                Moderator Board
              </Link>
            </li>
          )}

          {showAdminBoard && (
            <li className="nav-item">
              <Link to={"/admin"} className="nav-link">
                Admin Board
              </Link>
            </li>
          )}

          {currentUser && (
            <li className="nav-item">
              <Link to={"/user"} className="nav-link">
                User
              </Link>
            </li>
          )}
        </div>

        {/* passing a callback function to the Search component which will return
        the result returned from the api. Keeping the movie list state in app.js to map the movies here */}

        {locationState=='/register'||locationState=='/login'?null:<Search/>}


        {currentUser ? (
          <div className="navbar-nav ml-auto">
            <li className="nav-item">
              <Link to={"/profile"} className="nav-link">
                {currentUser.username}
              </Link>
            </li>
            <li className="nav-item">
              <a href="/login" className="nav-link" onClick={logOut}>
                LogOut
              </a>
            </li>
          </div>
        ) : (
          <div className="navbar-nav ml-auto">
            <li className="nav-item">
              <Link to={"/login"} className="nav-link">
                Login
              </Link>
            </li>

            <li className="nav-item">
              <Link to={"/register"} className="nav-link">
                Sign Up
              </Link>
            </li>
          </div>
        )}
      </nav>

      <div className="container mt-3">
        <Switch>
          <Route exact path={["/", "/home"]} component={Home} />
          <Route exact path="/login" component={Login} />
          <Route exact path="/register" component={Register} />
          <Route exact path="/profile" component={Profile} />
          <Route exact path="/films/:id" children={<MovieDetailContainer/>}/>
          <Route exact path="/films/:title" children={<MovieListComponent/>}/>
          <Route path="/user" component={BoardUser} />
          <Route path="/creator" component={BoardCreator} />
          <Route path="/admin" component={BoardAdmin} />
        </Switch>
      </div>
      {/* {selectedMovie && <MovieInfoComponent selectedMovie={selectedMovie} />} */}

      {/*<AuthVerify logOut={this.logOut}/> */}
    </div>
  );
};


export default App;

ANSWER

Answered 2022-Mar-12 at 23:47

The two paths "/films/:id" and "/films/:title" have the same specificity, so the one rendered first will be the one that is matched and rendered by the Switch component.

To resolve you need add something to differentiate them. I suggest a differentiating sub-path.

Example:

<div className="container mt-3">
  <Switch>
    <Route path="/login" component={Login} />
    <Route path="/register" component={Register} />
    <Route path="/profile" component={Profile} />
    <Route path="/films/:title/:id" component={MovieDetailContainer}/>
    <Route path="/films/:title" component={MovieListComponent}/>
    <Route path="/user" component={BoardUser} />
    <Route path="/creator" component={BoardCreator} />
    <Route path="/admin" component={BoardAdmin} />
    <Route path={["/", "/home"]} component={Home} />
  </Switch>
</div>

Source https://stackoverflow.com/questions/71453281

QUESTION

EventBus implementation using Coroutines and LiveData

Asked 2022-Mar-06 at 15:13

I need to broadcast events from different places within my app, and I need these events to be listened by different ViewModels. What I did is that I created a "custom" implementation of EventBus using Kotlin Coroutines, Channel more specifically. The implementation looks like this:

interface FlowEventBus {

    sealed class MessageEvent {
        data class MessageA(
            val someData: Int
        ) : MessageEvent()
        data class MessageB(
            val someOtherData: String
        ) : MessageEvent()
        object MessageC : MessageEvent()
    }

    suspend fun postMessage(messageEvent: MessageEvent)
    fun flowMessage(): Flow<MessageEvent>
}

class FlowEventBusImpl() : FlowEventBus {
    private val channel = Channel<FlowEventBus.MessageEvent>()

    override suspend fun postMessage(messageEvent: FlowEventBus.MessageEvent) {
        channel.send(messageEvent)
    }

    override fun flowMessage(): Flow<FlowEventBus.MessageEvent> {
        return channel.receiveAsFlow()
    }
}

Then in my ViewModels I use it like this

@HiltViewModel
class SomeViewModel @Inject constructor(
    private val flowEventBus: FlowEventBus
) : ViewModel() {
    
    val message = flowEventBus.flowMessage().asLiveData()
    // ...

The idea is that whatever Activity or Fragment is using this ViewModel, they can observe the message property and react to the "EventBus" events.

What's the problem?

Some of these events are unreliable. For example, let's say ActivityA is observing messages and it prompts a Snackbar every time we get a MessageC event. If the FlowEventBus broadcasts a MessageC event twice we'd only see the Snackbar pop once. I'm not very savvy about Kotlin Coroutines yet, what I think might be happening is the classing SingleLiveEvent scenario. My guess is that the asLiveData() extension turns the Flow into a MutableLiveData and if we set the same value twice, it will just ignore it. But I'm not sure how to introduce SingleLiveEvent here.

Any feedback is welcome, Thanks!

ANSWER

Answered 2022-Mar-01 at 18:40

Despite it is not a direct answer to your question... But

Why do you need the conversion from flow to live data? Just subscribe to flow on ui layer and populate the flow with necessary livedata features. Believe me, this will make your life much more easier.

I offer to do it by using implementation androidx.lifecycle:lifecycle-runtime-ktx:x.y.z and SharedFlow

In fragment:

with(viewModel) {
    eventsFlow.collectWhenStarted(viewLifecycleOwner, ::processEvents)
}

collectWhenStarted is a utility method which i offer to simplify subscribing a bit. It utilises using of launchWhenStarted method from the library:

inline fun <T> Flow<T>.collectWhenStarted(
    lifecycleOwner: LifecycleOwner,
    crossinline action: suspend (T) -> Unit
): Job = lifecycleOwner.lifecycleScope.launchWhenStarted {
    collectLatest {
        action.invoke(it)
    }
}

You can create similar utilities for other lifecycle events

To substitute a LiveData feature of persisting the data between configuration changes, background/foreground changes just convert a regular flow from domain layer to SharedFlow with replay. In a view model:

val eventsFlow: Flow<DataClass> = flowEventBus
    .flowMessage()
    .shareIn(viewModelScope, SharingStarted.Lazily, 1)

In case you are not distinct the emitted elements your EventBus shouldn't exclude any item you passed there

Check this article, the approach described there is close to what i suggest

Source https://stackoverflow.com/questions/71308693

Community Discussions, Code Snippets contain sources that include Stack Exchange Network

Vulnerabilities

No vulnerabilities reported

Install EventBus

You can download it from GitHub, Maven.
You can use EventBus like any standard Java library. Please include the the jar files in your classpath. You can also use any IDE and you can run and debug the EventBus component as you would do with any other Java program. Best practice is to use a build tool that supports dependency management such as Maven or Gradle. For Maven installation, please refer maven.apache.org. For Gradle installation, please refer gradle.org .