Add a Flutter View to an Android app
Integrating via a FlutterView requires a bit more work than via FlutterActivity and FlutterFragment previously described.
Fundamentally, the Flutter framework on the Dart side requires access to various activity-level events and lifecycles to function. Since the FlutterView (which is an android.view.View) can be added to any activity which is owned by the developer's application and since the FlutterView doesn't have access to activity level events, the developer must bridge those connections manually to the FlutterEngine.
How you choose to feed your application's activities' events to the FlutterView will be specific to your application.
A sample
#Unlike the guides for FlutterActivity and FlutterFragment, the FlutterView integration could be better demonstrated with a sample project.
A sample project is at https://github.com/flutter/samples/tree/main/add_to_app/android_view to document a simple FlutterView integration where FlutterViews are used for some of the cells in a RecycleView list of cards as seen in the gif above.
General approach
#The general gist of the FlutterView-level integration is that you must recreate the various interactions between your Activity, the FlutterView
and the FlutterEngine
present in the FlutterActivityAndFragmentDelegate
in your own application's code. The connections made in the FlutterActivityAndFragmentDelegate
are done automatically when using a FlutterActivity
or a FlutterFragment
, but since the FlutterView
in this case is being added to an Activity
or Fragment
in your application, you must recreate the connections manually. Otherwise, the FlutterView
won't render anything or have other missing functionalities.
A sample FlutterViewEngine
class shows one such possible implementation of an application-specific connection between an Activity
, a FlutterView
and a FlutterEngine.
APIs to implement
#The absolute minimum implementation needed for Flutter to draw anything at all is to:
- Call
attachToFlutterEngine
when theFlutterView
is added to a resumedActivity
's view hierarchy and is visible; and - Call
appIsResumed
on theFlutterEngine
'slifecycleChannel
field when theActivity
hosting theFlutterView
is visible.
The reverse detachFromFlutterEngine
and other lifecycle methods on the LifecycleChannel
class must also be called to not leak resources when the FlutterView
or Activity
is no longer visible.
In addition, see the remaining implementation in the FlutterViewEngine
demo class or in the FlutterActivityAndFragmentDelegate
to ensure a correct functioning of other features such as clipboards, system UI overlay, plugins, and so on.
Unless stated otherwise, the documentation on this site reflects the latest stable version of Flutter. Page last updated on 2025-01-16. View source or report an issue.