Instead of using a solve_layout function in the component, use property to hold
a layout cache.
This commit only implement the GridLayout and only the interpreter part
According to llvm-lines, MaybeAnimatedPropertyInfoWrapper::set_binding was
in the top 5 of functions with 15971 lines over 46 copies.
Split the code that does not depend on the Item parameter in a different function
Pass everything needed for delayed evaluation for
`PlatformWindow::font_metrics()` to permit caching the font matching
result in the Text/TextInput's rendering cache.
We query text metrics frequently for text items, for example when in
layouts. This requires font resolution, which is about to become more
much more expensive due to analysis of the underlying text. To speed
this up, the objective is to use the item rendering cache. Making that
work in turn requires querying all related properties inside a property
tracker. That means we need to delay querying anything related to that,
including the font request needed for the `font_metrics()` function on
the PlatformWindow trait.
Commit 843f52b3c5 erroneously applied the cross-axis
preferred size, which breaks the
images in buttons in the printer demo.
Also use the same value for shrink as for flex-grow, as advised by Olivier :-)
The component layout needs to be re-calculated. For some reason it is with
the Qt backend but not with GL.
Either way we can force it to re-calculate when the component changes.
It possibly doesn't get dirty when the dependencies are deleted.
Remove the intermediate properties for width and height and - just like
qt backend - apply the width and height in apply_window_properties
and when receiving a window resize event.
This also elimiates the get_geometry() getter as that would otherwise just
have been a FIXME'ed default().
Setting the redraw and window_properties tracker dirty won't have an
effect by itself, as nobody is tracking them in turn nor is any code
checking is_dirty(). Instead both trackers use callbacks to send events
(redraw or prop update), and so we can do these by hand with the already
existing request_redraw() call and the additional
request_window_properties_update() one.
* Provide an internal behavior parameter to run_event_loop() that we can use
from the preview to not quit when the last window was closed.
* Fix Drop for the winit event loop GraphicsWindow to drop the backend window correctly
when unmapping, not when the graphics window dies. Otherwise QuitOnLastWindowClosed doesn't work.
Test that assigning colors works:
* Test the implicit `Brush(const Color &)` C++ constructor
* Add derive_more::From to allow convenient conversion in Rust
* When assigning to brush properties in JavaScript, try at least to see if it's a color string (could be extended in the future)
* sixtyfps_timer_start needs to *take* the timer id out of the Rust
timer to avoid that the subsequent drop stops the timer again
* For the Qt event loop, call `timer_event()` once before entering
QCoreApplication::exec(), to schedule any timers that were started
beforehand.
* Added a way to quit the event loop gently, in order to use that
from the C++ unit test.
Similar to the window properties, use a property tracker with a change
handler in window to issue redraw requests. This allows eliminating the
forced repaints in the event loop after event processing and ensures
that the UI is repainted when programmatically setting a property, for
example.
Synchronize title/background/etc. once when the window is mapped and
afterwards lazily when the corresponding property tracker notifies us.
Since that callback can happen at any point in time and to also capture
potentially multiple changes, this first triggers a wakeup of the event
loop, when the actual application of properties happens.
A Property tracker can now be constructed with a callback that's invoked
when a property accessed during evaluate is changed.
The callback is guarded to be called only once until the tracker has
been evaluated. This is implemented by passing the information about
whether the property/tracker was already dirty before through the
mark_dirty() vtable call.
By default PropertyTracker::evaluate() registers the currently
evaluating binding/tracker as a dependency. This should help with
repeaters and other scenarios where in the run-time we use property
trackers but want to track the overall "dirtyness" in the window with
regards to whether a redraw is needed or not.
The new evaluate_as_dependency_root() function allows skipping this
mechanism and is used for the two trackers in the window.
