When an overlay handle dropped directly after pushing a new overlay, it
was possible for new overlays to be popped off improperly, causing a
subtraction overflow panic later.
Closes#98
This finishes my initial refactoring of the dynamic system to add
support for several dataflows including:
- Pure data sources that can be implemented using an `Owned<T>` at the
root of a graph of `Dynamic<U>`/`DynamicReader<U>`s.
- Read-only data sinks. I thought this would be more useful across other
widgets, but in general, Progress and Label seem like the only types
that this applies to currently.
- The ability to mix/match Dynamic/DynamicReader in tuple-based
for_each/map_each.
Refs #98
This refactor overhauls the reactive system to move all the reactive
methods to traits. The side effect of this change is that now
DynamicReader's API is the same as Dynamic's API, but because it only
implements Source<T>, DynamicReader does not offer any mutation
functions.
While it's unfortunate to have more traits to include to use Cushy, this
seems like the best option, and it offers a path to try to integrate
this into the tuple ForEach/MapEach traits. Unfortunately, my attempt at
doing those in this set of changes led to issues specifying generic
associated lifetimes for the DynamicGuard. But, I was also in the middle
of this larger refactoring, so it might be that a fresh attempt will
succeed.
This cascaded into a lot more work than expected. However, in general,
if one clones a `WidgetInstance` and shares it between two windows, it
should now work. Widget authors must ensure that when they cache
information, they do so with either a `WidgetCacheKey` or use a
`WindowLocal<T>` if per-window state is desired.
This is demonstrated in the debug-window example, where the counter of
open windows is next to a clone of the same button from the main window
that opens a new window.
While this was a workaround for a docs.rs issue (Px/Lp are not
linked), I decided having the shorter import path would look better in
the examples.
It probably wasn't necessary to update all of the references in the
internal code, but I decided it was worth the consistency.
- Blur no longer expands the shadow geometry, but instead is clamped to
avoid overlapping drawing calls.
- Overlay now handles hit tests correctly with regards to the original
relative widget.
- Align was using an Into conversion that wasn't actually correct,
causing the contents to not actually get aligned in some situations.
