Added horizontal and vertical alignment properties to Stack so that the origin of non-positioned children can be specified. Currently all of the non-positioned children just end up with their top-left at 0,0. Now, for example, you can center the children by specifying verticalAlignment: 0.5, horizontalAlignment: 0.5.
Added IndexedStack which only paints the stack child specified by the index property. Since it's a Stack, it's as big as the biggest non-positioned child. This component will be essential for building mobile drop down menus.
Added a (likely temporary) example that demonstrates IndexedStack.
Previously, RenderObjectElements didn't support being marked dirty. This
is fine, except for MixedViewport and HomogeneousViewport, which have
builder functions to which they hand themselves as a BuildContext. If
those builder functions call, e.g., Theme.of(), then when the theme
changes, the Inherited logic tries to tell the RenderObjectElement
object that its dependencies changed and that doesn't go down well.
This patch fixes this by making RenderObjectElement a BuildableElement,
and making MixedViewport and HomogeneousViewport hook into that to
rebuild themselves appropriately.
Also, this was only found at all because ThemeData didn't implement
operator==, so we were aggressively marking the entire tree dirty all
the time. That's fixed here too.
Also, I changed card_collection.dart to have more features to make this
easier to test. This found bugs #1524, #1522, #1528, #1529, #1530, #1531.
(These are changes cherry-picked from in-flight branches since they are
more independent and could be helpful even without those changes.)
- Change RouteBuilder's signature to take a single argument in which the
other fields are placed, so that we can keep iterating on those
arguments without having to break compatibility each time. Also, this
makes defining route builders much simpler (only one argument to
ignore rather than a variable number).
- Expose the next performance to RouteBuilders, since sometimes the
route itself might not be where it's used.
- Allow BuildContext to be used to walk children, just like it can for
ancestors
- Allow BuildContext to be used to get the Widget of the current
BuildContext
- Allow StatefulComponentElement to be referenced with a type
specialisation so that you don't have to cast when you know what the
type you're dealing with actually is.
This patch simplifies AnimationTiming and all the AnimatedValue base classes.
Also, make PopupMenu a stateless component because it has no state.
Fixes#1168
This patch converts drawer to using the "openDialog" pattern for managing its
state. Currently, the drawer entrance and exit animation aren't integrated with
the navigator's animation system because the drawer's animations can be stopped
and reversed, which the navigator can't yet understand. That means dismissing
the drawer via the system back button causes the drawer to be removed
instanteously.
Fixes#715Fixes#1187
The ShaderMask widget enables rendering its child with an alpha channel defined by a Shader. For example if the Shader was a linear gradient in alpha then the component behind the ShaderMask's child would appear wherever the gradient's alpha value was not fully opaque.
The card_collection.dart example demonstrates this. Select the "Let the sun shine" checkbox in the app's drawer.
You can now set an offset that will be used for the hit testing for
drops. (It doesn't move the feedback by default; use a Transform for
that.) I also made the default feedback not be Opacity 0.5 always.
Introduce a Draggable class that wraps all the logic of dragging
something and dropping it on a DragTarget.
Update examples/widgets/drag_and_drop.dart accordingly.
Make the performance/transition part of routes optional.
Initial snap offset support for ScrollableWidgetList (and ScrollableList<T>) and ScrollableMixedWidgetList. If a ```toSnapOffset(scrollOffset)``` function is provided, fling Scrolls will coast to the returned value. If ```alignmentOffset``` is specified then fling scrolls conclude when toSnapOffset's value lines up with the Scrollable widget's origin + alignmentOffset. For example if the Scrollable widget's height was 200.0, and alignmentOffset:100.0 was specified, then fling scrolls would end with the value returned by toSnapOffset() lined up with the center of the Scrollable.
This approach to Scrollable snapping assumes that the layout of whatever the Scrollable contains is known at the outset. This is often true however a ScrollableMixedWidgetList may not know its items' sizes until they've been reached by scrolling.
This is a first cut at snapping support. Among the things that remain to be done:
- Scrolling limits trump snapping. Snapping should probably trump scrolling limits.
- Drag scrolls aren't snapped. This may be desirable so perhaps the feature should be controlled with a flag.
- Specifying alignmentOffset as a percentage would probably be more convenient.
- It would be nice if one could wrap items in a SnapOffset value like: ```new SnapOffset(0.5, child: myItem)``` to snap to the center of the item.
Updated the CardCollection example: snapping and fixed size items can be turned on/off with Drawer checkboxes.
Also, introduce Colors and Typography to hold the material colors and the
typography declarations. Previously we expected clients of these libraries to
import them into a namespace, but that doesn't play nice with re-exporting them
from material.dart.
Move the animation libraries into src/animation and change importers to use
package:sky/animation.dart. Also, move scheduler.dart into the animation
library so that the animation library can be self-contained.
Turns out many of the functions on BoxConstraints weren't used or had callers
that could easily be updated to other functions. I've added dartdoc to all the
public functions as well as renamed some functions that had similar names but
did different things.
```
enum DismissDirection {
vertical,
horizontal,
left,
right,
up,
down
}
```
To only enable dismissing to the right create the `Dismissable` with `direction: DismissDirection.right`. By default direction is `DismissDirection.horizontal` (left or right).
Updated the card_collection "Swipe Away" demo with a drawer that can be used to select one of the three X axis dismiss directions. Currently the MixedViewport class doesn't support horizontal scrolling, so the demo doesn't support the X axis dismiss directions.
Add a way of having keys based on numeric types or DateTimes by having a ValueKey<T> class.
Remove the redundant ways of declaring things, except for leaving one shorthand -- you can say `new Key(s)` instead of `new ValueKey<String>(s)`.
