Goal

Fix the attachment picker's media capture flow not surviving Activity death (e.g. when the "Don't keep activities" developer option is enabled or the system kills the activity under memory pressure).

When the user opens the attachment picker and launches the device camera, the hosting Activity may be destroyed while the camera app is in the foreground. On return, the captured media was lost because:

1. AttachmentsPickerViewModel.isShowingAttachments was a plain mutableStateOf — reset to false on recreation — so the picker composable tree was never recomposed, and rememberLauncherForActivityResult callbacks were never re-registered to receive the pending result.
2. CaptureMediaContract.pictureFile / videoFile were private in-memory fields lost on process death, causing parseResult to return null even though the camera wrote a valid file to disk.
3. The camera was launched unconditionally via LaunchedEffect(Unit), so on activity recreation it would attempt to re-launch the camera instead of waiting for the pending result from the previous launch.

Note: I will create a separate PR for the XML UI SDK.

Implementation

AttachmentsPickerViewModel — persist picker visibility across process death

• Accept a SavedStateHandle as a constructor parameter (with @JvmOverloads for backward compatibility).
• Back isShowingAttachments with both MutableState (for Compose recomposition) and SavedStateHandle (for persistence). On recreation, the saved value is restored so the picker composable tree is recomposed and activity-result launchers can re-register.

MessagesViewModelFactory — supply SavedStateHandle to the ViewModel

• Override create(Class<T>, CreationExtras) to obtain a SavedStateHandle via CreationExtras.createSavedStateHandle() when constructing AttachmentsPickerViewModel. Falls back to the existing create(Class<T>) for all other ViewModels.

CaptureMediaContract — expose file references and add a creation callback

• Make pictureFile and videoFile public (annotated @InternalStreamChatApi) so they can be restored externally after process death.
• Add an onFilesCreated callback parameter, invoked inside createIntent after destination files are created, giving callers a chance to persist the file paths before the external camera activity starts.

CaptureMediaLauncher — persist destination file paths via rememberSaveable

• Introduce rememberCaptureMediaLauncherInternal which stores pictureFilePath and videoFilePath via rememberSaveable. On recreation, these paths are restored onto the CaptureMediaContract before rememberLauncherForActivityResult re-registers and dispatches the pending result.
• Add rememberCancelAwareCaptureMediaLauncher internal variant that forwards null on cancellation so callers can react (e.g. dismiss the picker).

AttachmentsPickerMediaCaptureTabFactory — guard against re-launching the camera

• Switch to the new rememberCancelAwareCaptureMediaLauncher instead of manually creating the contract.
• Track hasLaunched via rememberSaveable to prevent LaunchedEffect from re-launching the camera after activity recreation.

UI Changes

Testing

This can be tested by enabling "Don't keep activities" in Android Developer Options:

1. Open a channel and tap the attachment picker.
2. Switch to the media capture tab and launch the camera.
3. Capture a photo or video and confirm.
4. Verify the captured media is correctly attached to the message composer (instead of being lost or the camera re-launching).

Additionally, verify the normal (non-process-death) flow still works:

1. Open the attachment picker, capture media, and confirm it attaches correctly.
2. Open the attachment picker, launch the camera, then cancel — verify the picker dismisses properly.

Summary by CodeRabbit

Release Notes

• Bug Fixes

  • Improved state preservation for the attachments picker when the app is interrupted or backgrounded.
  • Enhanced media capture functionality with better handling of cancellations and process interruptions.

• Chores

  • Updated view model factory infrastructure for improved lifecycle management and state restoration.