Previously we tried to work around some possible badness from the engine
side, but now we are more assertive about the engine needing to do the
right thing.
Factor out a reusable interface called Decoration from BoxDecoration.
Make all the consumers of BoxDecoration and the erstwhile BoxPainter
into consumers of Decoration.
Make a BoxPainter be something you get from a Decoration, rather than
something to which you pass a BoxDecoration.
Rename Shape to BoxShape now that it's documented specifically as
applying to boxes.
Move EdgeDims to its own file.
Move FractionalOffset up so that it's with the other helper classes in
its file rather than alone at the end.
Minor change to RenderClipOval's hit testing to avoid taking an
unnecessary square root.
Rename BoxDecorationPosition to DecorationPosition since
RenderDecoratedBox now takes any Decoration.
Implement hit testing for rounded rects.
Rename AnimatedBoxDecorationValue to AnimatedDecorationValue, and make
it support lerping across any Decoration (by deferring to the objects
involved).
Users of MaterialApp can provide an onLocaleChanged handler that will be
called to asynchronously fetch locale-specific data. MaterialApp will
then instantiate a LocaleQuery that supplies the locale data to its
descendants.
Instead of PointerInputEvent having a "type" field, we now have a
different class for each pointer type.
This has ripple effects throughout the system.
I also did code cleanup in affected files while I was there.
Previously, we would assert with FlexJustifyContent.collapse if we ran out of
space. Now we do the same thing we do for the other types of justification,
which is to let the children's layout overflow.
Some paint bounds are in fact empty, e.g. at the start of a growing
animation if there's also a fade, the initial 0x0 box will also be
opacity:0, and might get a dedicated layer and PaintingContext.
This patch improves the repaint strategy for HomogeneousViewport so that the
list itself and every entry in the list has a repaint boundary. That means that
we only record list items as they enter the view.
Many of the widgets that use CustomPaint were spamming repaints because
CustomPaint repaints when the identity of the onPaint callback changes, which
it does every build for StatelessComponents.
This patch changes CustomPaint to use a CustomPainter, similar to the new
custom layout widgets. The CustomPainter has a `shouldRepaint` function along
with its `paint` function. This function gives clients explicit control over
when the custom paint object repaints.
This pattern breaks when using compositing because we need to lift those
operations into the compositing tree. This patch removes all the ones I could
find and adds an assert to help prevent more from getting introduced.
Fixes#191
This patch simplifies PaintingContext with several goals:
1) We now call a callback instead of assuming the caller has a single child to
paint. This change will let us handle render objects that wish to paint more
than one child.
2) We now avoid creating lots of empty picture layers because we don't eagerly
start recording pictures. Instead, we wait for the first caller to touch the
canvas before creating the picture recorder.
3) We now are more consistent about which values have incorporated the painting
offset.
Previously, we were putting a ForcedLayer just below the overlay, but that
causes trouble for routes like the popup menu that want to position themselves
inside the overlay. Instead, I've moved the ForcedLayer down into ModalRoute.
Also, rename ForcedLayer to RepaintBoundary, which is more descriptive of what
this widget does.
Fixes#485
Now we use a ForcedLayer in the navigator overlay to cache the recording for
each entry in the overlay. This mechanism just caches the display list, not the
underlying pixels.
Also, remove the "dispose" notification in the Layer tree because it was
disposing layer too eagerly. We don't actually need this notification for
anything other than eagerly freeing some C++ memory.
A common pattern is to use a Positioned with a Sized box to give both an offset
from the edge as well as a fixed size to the child. This patch rolls into into
the Stack layout algorithm for simplicity.
Fixes#250
Prior to this patch, MultiChildLayoutDelegate couldn't be re-entered because it
cleared _idToChild when unwinding its stack. Now we restore the previous value
of _idToChild when we unwind.
