This auto-formats all *.dart files in the repository outside of the
`engine` subdirectory and enforces that these files stay formatted with
a presubmit check.
**Reviewers:** Please carefully review all the commits except for the
one titled "formatted". The "formatted" commit was auto-generated by
running `dev/tools/format.sh -a -f`. The other commits were hand-crafted
to prepare the repo for the formatting change. I recommend reviewing the
commits one-by-one via the "Commits" tab and avoiding Github's "Files
changed" tab as it will likely slow down your browser because of the
size of this PR.
---------
Co-authored-by: Kate Lovett <katelovett@google.com>
Co-authored-by: LongCatIsLooong <31859944+LongCatIsLooong@users.noreply.github.com>
## Description
This adds a call to the `PlatformDispatcher` whenever the focus changes, so that the engine can decide what to do about view focus. This lets widgets use autofocus, and when they are focused their view will also receive focus.
## Related Issues
- Fixes https://github.com/flutter/flutter/issues/151251
## Tests
- Added a test and some methods to the `TestPlatformDispatcher` to allow introspection of the values sent.
## Description
This factors out a separate `RawView` that doesn't add a `MediaQuery` or a `FocusScope`. This PR also adds a new method `WidgetsBindingObserver.didChangeViewFocus` which allows the observer to know when the `FlutterView` that has focus has changed.
It also makes the `View` widget a stateful widget that contains a `FocusScope` and ` FocusTraversalGroup` so that it can respond to changes in the focus of the view.
I've also added a new function to `FocusScopeNode` that will allow the scope node itself to be focused, without looking for descendants that could take the focus. This lets the focus be "parked" at the `FocusManager.instance.rootScope` so that nothing else appears to have focus.
## Tests
- Added tests for the new functionality.
Reverts flutter/flutter#142339
In the original change one of the tests included the same view twice which resulted in a different failure than the expected one. The second commit contains the fix for this. I don't understand how this wasn't caught presubmit on CI.
Reverts flutter/flutter#141484
Initiated by: eliasyishak
This change reverts the following previous change:
Original Description:
The existing `runApp` bootstraps the widget tree and renders the provided widget into the default view (which is currently the implicit View from `PlatformDispatcher.implicitView` and - in the future - may be a default-created window). Apps, that want more control over the View they are rendered in, need a new way to bootstrap the widget tree: `runWidget`. It does not make any assumptions about the View the provided widget is rendered into. Instead, it is up to the caller to include a View widget in the provided widget tree that specifies where content should be rendered. In the future, this may enable developers to create a custom window for their app instead of relying on the default-created one.
The existing `runApp` bootstraps the widget tree and renders the provided widget into the default view (which is currently the implicit View from `PlatformDispatcher.implicitView` and - in the future - may be a default-created window). Apps, that want more control over the View they are rendered in, need a new way to bootstrap the widget tree: `runWidget`. It does not make any assumptions about the View the provided widget is rendered into. Instead, it is up to the caller to include a View widget in the provided widget tree that specifies where content should be rendered. In the future, this may enable developers to create a custom window for their app instead of relying on the default-created one.
This reverts commit
d24c01bd0c.
The original change was reverted because it caused some apps to get
stuck on the splash screen on some phones.
An investigation determined that this was due to a rounding error.
Example: The device reports a physical size of 1008.0 x 2198.0 with a
dpr of 1.912500023841858. Flutter would translate that to a logical size
of 527.0588169589221 x 1149.2810314243163 and use that as the input for
its layout algorithm. Since the constraints here are tight, the layout
algorithm would determine that the resulting logical size of the root
render object must be 527.0588169589221 x 1149.2810314243163.
Translating this back to physical pixels by applying the dpr resulted in
a physical size of 1007.9999999999999 x 2198.0 for the frame. Android
now rejected that frame because it didn't match the expected size of
1008.0 x 2198.0 and since no frame had been rendered would never take
down the splash screen.
Prior to dynamically sized views, this wasn't an issue because we would
hard-code the frame size to whatever the requested size was.
Changes in this PR over the original PR:
* The issue has been fixed now by constraining the calculated physical
size to the input physical constraints which makes sure that we always
end up with a size that is acceptable to the operating system.
* The `ViewConfiguration` was refactored to use the slightly more
convenient `BoxConstraints` over the `ViewConstraints` to represent
constraints. Both essentially represent the same thing, but
`BoxConstraints` are more powerful and we avoid a couple of translations
between the two by translating the` ViewConstraints` from the
`FlutterView` to `BoxConstraints` directly when the `ViewConfiguration`
is created.
All changes over the original PR are contained in the second commit of
this PR.
Fixes b/316813075
Part of https://github.com/flutter/flutter/issues/134501.
Towards https://github.com/flutter/flutter/issues/134501.
This change is based on https://github.com/flutter/engine/pull/48090. It changes the `RenderView` to be dynamically sized based on its content if the `FlutterView` it is configured with allows it (i.e. the `FlutterView` has loose `FlutterView.physicalConstraints`). For that, it uses those `physicalConstraints` as input to the layout algorithm by passing them on to its child (after translating them to logical constraints via the device pixel ratio). The resulting `Size` that the `RenderView` would like to be is then communicated back to the engine by passing it to the `FlutterView.render` call.
Tests will fail until https://github.com/flutter/engine/pull/48090 has rolled into the framework.
`FakeView` wraps the same underlying `FlutterView`. Sending semantics updates and Scene objects from multiple fake views into the same engine `FlutterView` violates contracts with the engine. This PR stubs out `render` and `updateSemantics` methods in `FakeView` classes to prevent that.
This unblocks https://github.com/flutter/engine/pull/48251, which implements multi-view semantics for web.
This change enables Flutter to generate multiple Scenes to be rendered into separate FlutterViews from a single widget tree. Each Scene is described by a separate render tree, which are all associated with the single widget tree.
This PR implements the framework-side mechanisms to describe the content to be rendered into multiple views. Separate engine-side changes are necessary to provide these views to the framework and to draw the framework-generated Scene into them.
## Summary of changes
The details of this change are described in [flutter.dev/go/multiple-views](https://flutter.dev/go/multiple-views). Below is a high-level summary organized by layers.
### Rendering layer changes
* The `RendererBinding` no longer owns a single `renderView`. In fact, it doesn't OWN any `RenderView`s at all anymore. Instead, it offers an API (`addRenderView`/`removeRenderView`) to add and remove `RenderView`s that then will be MANAGED by the binding. The `RenderView` itself is now owned by a higher-level abstraction (e.g. the `RawView` Element of the widgets layer, see below), who is also in charge of adding it to the binding. When added, the binding will interact with the `RenderView` to produce a frame (e.g. by calling `compositeFrame` on it) and to perform hit tests for incoming pointer events. Multiple `RenderView`s can be added to the binding (typically one per `FlutterView`) to produce multiple Scenes.
* Instead of owning a single `pipelineOwner`, the `RendererBinding` now owns the root of the `PipelineOwner` tree (exposed as `rootPipelineOwner` on the binding). Each `PipelineOwner` in that tree (except for the root) typically manages its own render tree typically rooted in one of the `RenderView`s mentioned in the previous bullet. During frame production, the binding will instruct each `PipelineOwner` of that tree to flush layout, paint, semantics etc. A higher-level abstraction (e.g. the widgets layer, see below) is in charge of adding `PipelineOwner`s to this tree.
* Backwards compatibility: The old `renderView` and `pipelineOwner` properties of the `RendererBinding` are retained, but marked as deprecated. Care has been taken to keep their original behavior for the deprecation period, i.e. if you just call `runApp`, the render tree bootstrapped by this call is rooted in the deprecated `RendererBinding.renderView` and managed by the deprecated `RendererBinding.pipelineOwner`.
### Widgets layer changes
* The `WidgetsBinding` no longer attaches the widget tree to an existing render tree. Instead, it bootstraps a stand-alone widget tree that is not backed by a render tree. For this, `RenderObjectToWidgetAdapter` has been replaced by `RootWidget`.
* Multiple render trees can be bootstrapped and attached to the widget tree with the help of the `View` widget, which internally is backed by a `RawView` widget. Configured with a `FlutterView` to render into, the `RawView` creates a new `PipelineOwner` and a new `RenderView` for the new render tree. It adds the new `RenderView` to the `RendererBinding` and its `PipelineOwner` to the pipeline owner tree.
* The `View` widget can only appear in certain well-defined locations in the widget tree since it bootstraps a new render tree and does not insert a `RenderObject` into an ancestor. However, almost all Elements expect that their children insert `RenderObject`s, otherwise they will not function properly. To produce a good error message when the `View` widget is used in an illegal location, the `debugMustInsertRenderObjectIntoSlot` method has been added to Element, where a child can ask whether a given slot must insert a RenderObject into its ancestor or not. In practice, the `View` widget can be used as a child of the `RootWidget`, inside the `view` slot of the `ViewAnchor` (see below) and inside a `ViewCollection` (see below). In those locations, the `View` widget may be wrapped in other non-RenderObjectWidgets (e.g. InheritedWidgets).
* The new `ViewAnchor` can be used to create a side-view inside a parent `View`. The `child` of the `ViewAnchor` widget renders into the parent `View` as usual, but the `view` slot can take on another `View` widget, which has access to all inherited widgets above the `ViewAnchor`. Metaphorically speaking, the view is anchored to the location of the `ViewAnchor` in the widget tree.
* The new `ViewCollection` widget allows for multiple sibling views as it takes a list of `View`s as children. It can be used in all the places that accept a `View` widget.
## Google3
As of July 5, 2023 this change passed a TAP global presubmit (TGP) in google3: tap/OCL:544707016:BASE:545809771:1688597935864:e43dd651
## Note to reviewers
This change is big (sorry). I suggest focusing the initial review on the changes inside of `packages/flutter` first. The majority of the changes describe above are implemented in (listed in suggested review order):
* `rendering/binding.dart`
* `widgets/binding.dart`
* `widgets/view.dart`
* `widgets/framework.dart`
All other changes included in the PR are basically the fallout of what's implemented in those files. Also note that a lot of the lines added in this PR are documentation and tests.
I am also very happy to walk reviewers through the code in person or via video call, if that is helpful.
I appreciate any feedback.
## Feedback to address before submitting ("TODO")
* Reland "Inject current `FlutterView` into tree and make available via `View.of(context)` (#116924)"
This reverts commit 9102f2fe0bd26db6074ac4a17785296cd341ecb9.
* remove window placeholder
