These widgets were designed in CSS where you need to specify a layout model for
your children. This patch updates them to the modern style of just taking a
unique child.
Fixes#755
When laying out positioned children inside a stack, we should give them
unbounded constraints because if they draw outside of the stack, we'll just
clip them.
Changed the pageable_list.dart example: tapping on the toolbar changes
the scroll direction. This exposed some problems:
- Scrollable.syncFields() didn't update scrollDirection
- Viewport updated its RenderObject fields in the wrong order
- FixedHeightScrollable scrollDirection changes didn't update the scrollBehavior
There may be similar problems with VariableHeightList and ScrollableViewport.
I will fix those in a separate CL.
- PageableList extends ScrollableList
One fixed width or height item is visible and centered at a
time. Fling and drag gestures scroll to the next/previous item.
- Scrollable.scrollTo(), Scrollable.scrollBy(), ensureWidgetIsVisible() API changed
The named animation parameter for these methods was replaced by
duration and curve. All of the methods now return a Future. The Future
completes when the scroll does.
This change eliminates the need for Scrollable to temporarily take ownership
of a ValueAnimation object (see #645).
- Using Future.then() instead of an AnimationPerformance status listener
In ensure_visible.dart _handleTap() uses ensureWidgetIsVisible() to
center the card roughly as before and then. When the implicit scroll
animation is complete, it changes the centered card's label font. The
change is made when the Future returned by ensureWidgetIsVisible()
completes.
- FixedHeightScrollable's itemHeight parameter is now itemExtent
If scrollDirection is ScrollDirection.vertical (the default) then itemExtent should
be the height of each item; otherwise it should be the width of each item.
Replaced _velocityForFlingGesture() in scrollable.dart with Scrollable._eventVelocity()
The original version clamped pixels/ms against pixels/sec constants. The new version
also deals with scrollDirection.
- Plumbed scrollDirection though FixedHeightScrollable and ScrollableList
Both classes should now support horizontal scrolling.
... and reattach fitness to the build. We detached fitness from the build
because it was seeing an old version of playfair that didn't work with the most
recent version of the Sky package.
Unhook fitness from the build to work around build break in playfair. We
updated the Sky package in an incompatible way, which means we need to roll in
a new playfair package to build fitness.
Similar to widgets.dart, rendering.dart exports the entire rendering layer.
Also, update the examples to use rendering.dart and widgets.dart. Also clean up
some exports so that the examples have more sensible imports.
Sadly, box.dart has grown much longer than 1000 lines. This patch splits it up
into several files based on the class hierarchy. Fortunately, many of these
classes are loosely coupled to each other.
These properties should apply to foreground images as well as background
images. Also, rename these types from BackgroundFit and BackgroundRepeat
because they apply to things other than backgrounds.
We had a remarkable number of analyzer failures.
I'll fix the bots to analyze across the whole project
in a follow-up patch, that should prevent this
in the future.
@abarth
Widgets that want to receive drops should include a DropTarget in their build.
Currently there's no widget for initiating a drag. Components can use the
DragController directly. In the future, we'll probably want to add a Draggable
that knows how to do some of this work automatically.
Fixes#612
