Scaffold | Android 基础开发框架，帮助开发者快速搭建基础模块 | Android library

the best way to set the theme to make it sperate file of theme and call in main file and the primary color is working for me theme: ThemeData(), like that you can also set theme of your icon and also you can set theme of your text.

I'm not sure where the error was from, but switching flutter channel from master to stable fixed it.

I've worked with Compose since the early alpha stages and became quickly disappointed with Google's lame attempt at providing a more modern approach to navigating a single-activity app. When you consider that Android's view-based system was entirely replaced with the declaration approach that Compose uses, you have to seriously wonder why they would stick with a navigation controller that doesn't allow you pass objects from one screen to another. There was also the issue that adding animation when transitioning from one screen to another was an afterthought. There is an add-on that supports animation transitions.

But perhaps the worst thing about Compose was its lack of handling device configuration changes. Under the older view-based system, you defined your layouts in xml files and placed these in resource folders that had qualifiers in the folder name that would aid Android in picking the correct layout based on things like screen density, orientation, screen size, etc. That went out the window with Compose. Eventually Google did add APIs to handle composables that need to be selected based on screen sizes and densities. But ultimately, you end up writing this decision logic within your composable and your code starts to look like spaghetti. Google's Android team completely forgot about the most basic "Separation of Concerns" when they chose to mix UI layouts with the logic that determines which layout gets selected. Designing your composables is one thing and how they get selected is another. Don't mix the two. Your composables become increasingly less reusable when you integrate those APIs. The original developers of Android (who weren't from Google) knew well enough to have the operating system manage the layout selection based upon changes to device configurations.

I chose to create my own framework that handles navigation and manages composables in almost an identical way that the view-based system works. It also remedies the issue of not being able to pass objects from screen to screen. If you are interested, you can check it out at:

https://github.com/JohannBlake/Jetmagic

So to answer you question about whether Compose Navigation is good for navigating, I would have to say no. I have worked with it and have found it severely lacking. If you want to be just-another-run-of-the-mill-Android-developer, then use Compose Navigation. But if you want to chart your own path and liberate yourself from Google's poor design practices, then use Jetmagic or even better, create your own navigation framework. It isn't that hard.

It is the expected behaviour. You are constructing two separate app bars for both the screens so they are bound to flash. This is not the correct way. The correct way would be to actually put the scaffold in your main activity and place the NavHost as it's content. If you wish to modify the app bar, create variables to hold state. Then modify them from the Composables. Ideally, store then in a viewmodel. That is how it is done in compose. Through variables.

Thanks

This is a common mistake that happens when using Inherited Widgets like MediaQuery. Now you may not be using it explicitly but from your description it seems that Flutters' showModalBottomSheet method maybe using it.

The error is telling you that no MediaQuery ancestor(i.e. WidgetsApp, CupertinoApp or MaterialApp) could be found above context. It means above this context:

Nesting of NavHost is not allowed. It results in ViewModelStore should be set before setGraph call Exception. Generally, the bottom nav is outside of the NavHost, which is what the docs show. The recommended approach is a single NavHost, where you hide and show your bottom nav based on what destination you are on.

As mentioned by the comment on the question and on this site

https://github.com/dotnet/Scaffolding/issues/1713

Removing the nuget package Microsoft.AspNetCore.Identity from all projects in the relevant solution solves the problem.

In many cases (also in mine) its enough to reference the nuget package Microsoft.AspNetCore.Identity.EntityFrameworkCore

Try this please

Remember that each of the on variables is a callback. onScreenChange implicitly passes the variable it as String, but it is not necessary to use the variable within your callback.

1. it is implicitly passed, but in the GitHub link you gave, the programmer decided to rename it to onScreenChange. That callback then was passed to OverviewBody, which overrides the default {}, as you said. What I don't understand about your question is where onAccountClick is coming from. That is not a parameter of OverviewBody, according to the GitHub code.

2. content has a parameter for another callback, which you noticed. The body variable for each class in the enum is then invoked, and the callback parameter is passed to the invocation. In the future, that callback will only be used by OverviewBody. Remember that body(callback) is the same as body.invoke(callback).

I hope this helps. Please let me know if anything needs some more explanation.

For further reference:

• Kotlin Lambda Docs

Additional Content Edit:

1. I see the parameters in your code, not the one on GitHub. My apologies for missing that.
2. body is a variable function. This means that the variable function can be invoked, either by writing body(...) or body.invoke(...). The String parameter it, which is passed implicitly, is ignored and the default values are used, unless specified like you suggested (onAccountClick=it).