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I am new to JetPack Compose. I am leanring Compose and was following https://developer.android.com/jetpack/compose/tutorial

But when I ran the application in my android device, the app was extremely slow. Simple things like expanding long message and changing color of message is taking so much time.

I have googled the problem and found:

1. https://www.reddit.com/r/androiddev/comments/oatiur/why_simple_app_with_jetpack_compose_is_5x_times/
2. https://github.com/android/compose-samples/issues/21
3. https://jetc.dev/slack/2021-03-14-why-so-slow.html
4. Jetpack Compose Performance Issue that only occurs in multi module project

But none of these were helpful to me.

If there is any confusion, please tell in the comments.

so i am trying to Rebuild Project then this error happened help im new to android and i am just following a tutorial to learn more about android, i am trying to implement Hilt-Dagger into my application but idont know how to fix this error. here is my gradle and Error:

I am a home user working on Windows 7 X64. I have a problem with my signed APK.
My app is only for home use and learning. I won't submit to Google Play.
When installed, it shows

Blocked by Play Protect.
Play Protect doesn't recognise this app's developer.
Apps from unknown developers can sometimes be unsafe.

Tools:

friends, I have a question. I can use the fragment in the image in an activity. But I want to be able to view this fragment in a different activity. Is it possible? I used a structure like the one in the image, but I am also writing the error I received. I would be glad if you could help.

BreakingNewsFragment.kt

I use Laravel. I saved the array to the database in the form of a string like this. enter image description here

Then I want to summarize each piece of data the same. for example "Web Dev" is 5, "Android Dev" is 3. how to do this? I have used "Has" but the method is undefined.

I'm using annotated attributes all over my Android project to bind Views and events to fields and methods.

I want to add three divs in the same line, but when I add the second div it's displayed below the first div. I don't know how to fix this problem.

When I try to upload my Android App Bundle to the Google Play Console, I get this generic error message saying "Couldn't upload. Try again.".

I've already tried:

• making sure my versionName and versionCode are unique among all uploaded artifacts
• making sure that the .aab/.apk is signed with the proper key
• re-uploading the .AAB file
• re-uploading the .APK file
• checking status of google services to make sure that there isn't a mass outage
• asking my senior Android dev what's up

How do I resolve this error and upload my .AAB or .APK?

I'm working on an Android piano "quiz" app - users tap on the piano keys and then click the yellow "check" button to submit the answer for evaluation and see the correct answer drawn on the piano. The main QuizActivity has this layout:

The upper part of the screen hosts a couple of controls (Text, submit buttons, etc.). The lower part of the screen is occupied by a custom PianoView component, that handles drawing of the piano keyboard.

According to the MVVM principles, the PianoView should have its own PianoViewModel, that stores its state (i.e. currently pressed keys, highlighted keys, etc...) in a KeysStateRepository. The enclosing QuizActivity should also have a QuizActivityViewModel, that handles the various controls (submitting an answer, skipping a question...). The QuizActivityViewModel needs to be able to query the selected keys from the PianoView (or rather from its KeysStateRepository), submit them to the Domain layer for evaluation and then send the results back to the PianoView for visualization.

In other words, the QuizActivity's ViewModel should own/be a parent of the PianoView's ViewModel to facilitate communication and data sharing.

How can I model this parent-child relationship to communicate between the ViewModels?

AFAIK a ViewModel cannot depend on another ViewModel (What would I pass as the ViewModelStoreOwner to obtain a ViewModel in another Viewmodel?). I don't think it's possible to achieve with Dagger-Hilt at least.

Three solutions to work around this problem came to mind, all of them unusable:

The Android dev docs recommend using a shared ViewModel to facilitate sharing of data between two Fragments / Views. However, this does not fit my use-case. The PianoView (or its ViewModel) should be the sole owner of its state with a Repository scoped to its ViewModel. Otherwise, the PianoView component would not be reusable. Consider for example another Activity, where I'd like to have two independent PianoView instances visible:

Reusing a Shared ViewModel from the quiz activity would be obviously wrong, because it contains irrelevant methods and logic (i.e. submitting quiz answers) and would not fit the two-keyboard scenario.

A similar problem was tackled on Reddit with a proposed solution of using a shared instance of the repository. However, using a @Singleton KeyStateRepository would once again prevent the two independent keyboards to display different data.

I could in theory create 2 independent ViewModels and 2 KeyStateRepository instances. The ViewModels would subscribe to an event bus. Each time a ViewModel invokes a mutable operation on its repository, it would also fire an event and the operation would get replicated via the other ViewModel subscribed to the same event bus.

However, this feels like a fragile & complicated hack. I'd like to have a simple MVVM-compatible solution. I can't believe a simple parent-child relationship for two UI components is something unattainable in MVVM.