Introduce an AndroidView widget and a RenderAndroidView render object. #19565
Conversation
RenderAndroidView is responsible for sizing and displaying an embedded Android view. AndroidView is responsible for creating and disposing the Android view and is using RenderAndroidView to display it.
|
@HansMuller would love to get your feedback on this |
|
|
||
| /// Embeds an Android view in the Widget hierarchy. | ||
| /// | ||
| /// Embedding Android views is an expensive operation and should be avoided when possible. |
There was a problem hiding this comment.
May need a bit more elaboration like what's the proposed alternative or why this exists (i.e. what are reasonable use cases)
| class AndroidView extends StatefulWidget { | ||
| /// Creates a widget that embeds an Android view. | ||
| /// | ||
| /// The `viewType` parameter must not be null. |
| } | ||
|
|
||
| class _AndroidViewState extends State<AndroidView> { | ||
|
|
There was a problem hiding this comment.
uber nit: ha looks like google3 java style? I don't see whitespace at class start/end elsewhere in our codebase for consistency
| import 'object.dart'; | ||
|
|
||
|
|
||
| enum _PlatformViewState { |
There was a problem hiding this comment.
Please don't use SCREAMING_CAPS
| /// [RenderAndroidView] is responsible for sizing and displaying the Android view. | ||
| /// | ||
| /// See also: | ||
| /// * [AndroidView] which is a widget that is typically used to show an Android view. |
There was a problem hiding this comment.
I think you can omit "typically"
|
|
||
| /// A render object for an Android view. | ||
| /// | ||
| /// [RenderAndroidView] is responsible for sizing and displaying the Android view. |
There was a problem hiding this comment.
the Android view => an Android View
Maybe View should be a link to https://developer.android.com/reference/android/view/View
| /// } | ||
| /// ``` | ||
| /// | ||
| /// The Android view lifetime is the same as the lifetime of the [State] object for this widget. |
| /// | ||
| /// The Android view lifetime is the same as the lifetime of the [State] object for this widget. | ||
| /// When the [State] is disposed the platform view (and auxiliary resources) are lazily | ||
| /// released (some resources are immediately released and some by platform garbage collector). |
There was a problem hiding this comment.
This would be a good place to provide an State disposal example or two. You could say it general terms, like: A stateful widget's state is disposed the the widget is removed from the tree or when it is moved within the tree. If the stateful widget has a key and it's only moved relative to its siblings, or it has a [GlobalKey] and it's moved within the tree, it will not be disposed.
There was a problem hiding this comment.
thanks, copy pasted 😄
|
|
||
| /// Embeds an Android view in the Widget hierarchy. | ||
| /// | ||
| /// Embedding Android views is an expensive operation and should be avoided when a Flutter |
There was a problem hiding this comment.
Should we explain that an embedded android view behaves just like a normal Flutter widget with respect to painting and input. And what about layout? I imagine that we need to explain that the parent has to constrain the size of its AndroidView.
There was a problem hiding this comment.
Added:
/// The embedded Android view is painted just like any other Flutter widget and transformations
/// apply to it as well.Anything else to add here?
I'll leave the comment about input to the PR where I add input support.
| /// A [PlatformViewFactory](/javadoc/io/flutter/plugin/platform/PlatformViewFactory.html) | ||
| /// for this type must have been registered. | ||
| /// | ||
| /// See also: [AndroidView] for an example of registering a platform view factory. |
There was a problem hiding this comment.
Are there any predefined view types?
There was a problem hiding this comment.
there aren't... we're going to add them in plugins.
| } | ||
|
|
||
| class _AndroidViewState extends State<AndroidView> { | ||
| int id; |
There was a problem hiding this comment.
_createNewAndroidView is private, maybe these state vars should be private as well.
|
|
||
| @override | ||
| void performResize() { | ||
| size = constraints.biggest; |
There was a problem hiding this comment.
What happens if the constraints aren't bounded?
There was a problem hiding this comment.
Red screen of death 😨
That's the same behavior we have for Texture.
Not sure what better to do here, I added a note about this to the class comments for the render object and the widget.
| await _viewController.setSize(size); | ||
| // We've resized the platform view to targetSize, but it is possible that | ||
| // while we were resizing the render object's size was changed again. | ||
| // In that case we will re-iterate to resize the platform view again. |
There was a problem hiding this comment.
I don't think re-iterate is a word, probably just say something like: In that case, set the view controller's size again.
| return; | ||
|
|
||
| context.addLayer(new TextureLayer( | ||
| rect: new Rect.fromLTWH(offset.dx, offset.dy, size.width, size.height), |
|
How should I use AndroidView to embed a WebView? |
|
AndroidView is not yet ready to be used. |
6 participants
RenderAndroidView is responsible for sizing and displaying an embedded
Android view.
AndroidView is responsible for creating and disposing the Android view
and is using RenderAndroidView to display it.
#19030