drawer | Drawer navigator for React Navigation | Mobile Application library

I'm doing a Group Chat with Firebase and currently I'm using a RecyclerView to display chat messages and I'm having a problem. When you open the app in the fragmented home and you go to chat activity and start chatting (adding elements to recycler view) all goes fine. But, when you go via the NavigationDrawer to another fragment and get back to the chat fragment using again this Navigation Drawer. When you add one element in the chat it appears all in the blank it just displays the last message. Anybody knows why does this happens?

Here I leave the RecyclerView Adapter Code:

I have an Activity. In the Activity, I have a Navigation Drawer on the Left and a fragment. In the Navigation Drawer, I have a textview for Name. I want to set the text view from Fragment to Navigation Drawer in activity

Here's the image:

Here the Code in Activity(MyActivity.java):

I have an application under construction using the Navigation Drawer Activity which is the one with the left menu like the old version of Google PlayStore:

As you know the design comes bundled with a FAB (FloatingActionButton):

Now, in the left side menu you see these three Fragments:

I wanted to know, how do I assign different actions to the FAB when I change the Fragment? From the MainActivity I see that there is the k but I do not understand how to assign a different functionality to it, since when changing the Fragment, the same FAB is still there and executes the same action that in this case is a Toast:

I cannot seem to see what is going wrong here, pretty basic usage to useContext and useState hooks. I have a darkModeContext where I am literally just flipping the boolean for darkMode, but whilst trying to flip it for the context I am getting setContext is not a function.

I took some code out from the navDrawer to make it easier to see but here is the error I am getting along with the code:

DarkThemeContext.js

Stackblitz for this problem. That's the closest I could get.

I'm using Material Drag & Drop. The result I'm looking for is to clone an item from a LIST and put into another list, which is visually an AREA, but that's the "catch", keeping the dropped "coordinates" (x,y) on that area.

That's my HTML code:

I am really newbie in Flutter and SQLite. I need to store some data got from a DB into a global variable (in this code it's a local variable just for exemplification) and I don't know:

1. where is the best point I can do it (now I put it in the homepage's initState method);
2. how I can store future data in a no-future variable.

Below is the method for the data extraction

I have two selects, I want to configure them so that only a certain amount of options show in the second select, depending on which first selection is chosen.

I found some code from this post and I've tried to edit it for my situation, as I need too keep the values as they are, because I'm using them in a calculator that needs them like that.

If any one could help me fix/finish this code so it works, it would be much appreciated!

What I'm trying to achieve:

• If the user selects combo-x1, bench-x1 option only shows
• If the user selects combo-x2, bench-x1 option + bench-x2 option only shows
• If the user selects combo-x3, bench-x1 option + bench-x2 + bench-x3 option only shows
• If the user selects combo-x4 up to combo-8, all options show

Here is the JSFiddle: https://jsfiddle.net/mbxz186q/

But here is the code so far as well:

I made a website with PageController to control the scroll of some screens. And I made a menu section with screen names, and when any of them are pressed, the user will navigate to the respective screen.

The app is working fine. But I refactored the menu button so I can control it's style, and to add animation in the future.

But when I refactored the button, I can't pass the PageController index, or the nextPage function.

That's why I thought of using the provider package. However, I didn't the package before, and my setup seems complex. For I should pass the PageController state to the button, and the button should send the nextPage function with a new number.

How can I achieve this?

Here's my code:

The button:

I created a responsive navigation bar using the React material UI Appbar component.

If the screen size is large, it shows tabs in the navigation bar. If the screen size is medium or smaller, it uses material UI responsive drawer to show the navigation bar (home, about, etc) on the left side right below the navigation bar. How can I move the responsive material UI drawer to the right?

https://material-ui.com/components/drawers/#responsive-drawer