This implements an update to the look of the Slider widget.
Specifically, it does the following:
* Adds the ability to customize the colors of all components of the slider
* Adds the ability to customize the shape of the slider thumb and value indicator
* Adds the ability to show the value indicator on continuous sliders
* Updates the default value indicator to be a "paddle" shape with new animations.
* Changes the tick marks to be visible all the time on discrete sliders
* Fixes a memory leak of an animation controller.
* Removes "thumbOpenAtMin" flag, which is no longer needed, and can be emulated by the
custom thumb shape support. It was not widely used.
* Adds tests for all of the new features.
Fixes#13743Fixes#12379
Follow-up to #13745
Also adds an option to hide gestures introduced by `InkWell` and `InkResponse` from the semantics tree (see also `GestureDetector.excludeFromSemantics`).
Applies media padding (e.g. iPhone X safe area insets) to the Material Design demos in the Gallery.
Covers the following demos:
* Buttons (via the TabbedComponentDemoScaffold change)
* Cards
* Expansion panels
* Grid list
* Icons
* Images (via the TabbedComponentDemoScaffold change)
* Page Selector
* Progress Indicator
* Scrollable tabs
* Selection controls (via the TabbedComponentDemoScaffold change)
* Snack bar
* Tabs
* Text fields
* Tooltips
Fixes#13594
Fix the dismissible demo in the gallery (make it actuall update when you pick something from its menu; give it a better affordance for resetting once you've dismissed everything).
Improve some docs.
Fix various flinging bugs with dismissible. Add tests for those cases.
Add a feature to flutter_test to support a drag-then-fling gesture (used by the flinging tests).
In order to allow chips to be properly drawn when they expand in size (without
using IntrinsicHeight), I needed a BoxDecoration shape that would be dependent
upon the rendered height of the widget. This seemed to be pretty generally
useful, so I added a new ShapeDecoration called StadiumBorder. It uses the
minimum dimension to adjust the BorderRadius of a rounded rect in the shape
decoration.
I also converted some uses of BoxShape to be case statements, updated the
chips to use the StadiumBorder decoration, and updated some of the metrics to match
the Material spec, as well as implementing lerping to and from StadiumBorder.
This lets us preview widgets in the gallery using small, normal, large, and HUGE text.
Added selections to the main drawer for these options. Defaults to "normal", obviously.
Previously, we used `Alignment`, which was difficult to understand. Now,
we just use an `Offset` scaled to the child's size, which is much easier
to understand.
Also, clean up the menus code a bit.
Also, make it easier to write a PopupMenuEntry that has itself many
items (for example, the way Chrome's menu has icons in a row).
Minor fixes throughout, e.g. removing trailing commas from the end of sample code expressions, changing headings to "sample code" more consistently, removing stale todos, fix typos in a private method name, minor grammar fixes, added some clarifications to CircularProgressIndicator, LinearProgressIndicator, CrossAxisAlignment, added some cross-references to various members, made it slightly clearer that layout algorithms are implementation details.
Clarified "elevation" throughout.
Added docs to InkResponse and InkWell.
Added sample code for: SliverAppBar, Card, ListTile, EdgeInsets, Row, Column, CustomScrollView, ListView, SliverFixedExtentList, and SliverGrid.
Fixes#10317.
Fixes#10316.
Fixes#10267. (sort of, see comment therein)
Fixes#9331. (sort of, see comment therein)
Fixes#9407. (sort of, see comment therein)
* Adjust the defaults behaviour of scroll views.
Now, primary scroll views scroll by default. Others only scroll if necessary.
* apply suggested changes
* Add a text formatter interface used by EditingText. Provide some default implementations.
* self nits
* Handle -1 selection offsets
* review notes
* simplify regular expression
* Add whitelisting formatters. Use a custom phone number formatter in text demo.
* review notes
* not being able to addAll(null) is pretty annoying
* review notes
* partial tests
* Add tests
* didn’t end up needing mockito
* move to services
