When opting into the Skia renderer, we default to metal on macOS and D3D on Windows.
However if you want to develop a cross-platform application with Skia and
for example rely on OpenGL to be able to implement an OpenGL underlay or overlay,
then we need the ability to explicitly opt into skia's GL renderer.
cc #1445
and use Rc<dyn PlatformWindow> instead. The alias has to stay with the ffi
functions though and the item vtable definitions,
because we don't have an Rc<> template in C++.
One key difference to the Rust way is what `slint::Window` means. In
Rust that holds the `WindowInner` and `slint::Window` is only exposed as
`&slint::Window`. This is possible because the component owns the
`Rc<dyn PlatformWindow>`, which has a function to return the
`&slint::Window`.
In C++ `slint::Window` is also exposed as `slint::Window&` in the
`window()` getter, but there's no way to get a reference to a C++
wrapper for the Rust `&slint::Window` that the `PlatformWindow` trait
returns. Therefore in C++ `slint::Window` wraps `Rc<dyn
PlatformWindow>`.
Previously: Window is an Rc<WindowInner>, which has an Rc<dyn
PLatformWindow> - and weak references the other way around.
Now: Rc<dyn PlatformWindow> is the root of window ownership. The impl
PlatformWindow has a slint::api::Window, which just holds a WindowInner.
This change is incomplete on a few levels, mainly that neither of the
code generators nor the interpreter is ported.
Split backend-gl-* into eventloop-winit-* and renderer-femtovg.
The old feature names are still available.
For consistency eventloop-qt and renderer-qt are aliases for backend-qt.
For embedded images the path is empty but we unconditionally used it to create a TextureCacheKey,
which clashes.
Instead, preserve and store the ImageCacheKey in the ImageInner variants.
This includes the cache of decoded images, the HTMLImage element support
and the SVG rendering adapter.
The objective is that Image holds an ImageInner, which is not a path
anymore that the backend has to process, but instead always either
decoded image data, a pointer to a static texture or an SVG tree that
can be rendered to the desired size.
With two-way bindings and dynamically created components it is possible
to end up with a binding to a property where the binding outlives the
property (see #1394).
With rust generated code, this means on binding evaluation, the upgrade
from self_weak to self_rc fails and panics.
With the interpreter we moved a VRef into the binding closure, which
ends up being a dangling pointer and causes memory corruption. This
change aligns the interpreter with the Rust way of creating closures by
creating the VRc first, moving a VWeak into the callback and binding
closures and upgrading that.
I want to track component structure changes in the window without
generating more code. So use a more generic name for the init_*_items
functions, so that I can add the functionality I need in there.
Also add a register_component to PlatformWindow and call that.
I want a more generic name as I want to do to track component structure
changes in addition to resource freeing and I do not want to add another
call into the generated code.
Implement basic accessibility (a11y) support, using the Qt backend.
_This should get us started, but accessibility support is an additional way to interact with UIs that is very different from the "graphical way" most users will interact with the UI. No single PR will "make a toolkit accessibility", this needs to be an ongoing effort!_
Parts of this PR:
* Add functions to access a11y-related properties to Component
* Add helper functions to Item struct
* Handle accessible- properties in the compiler
* Add documentation, add description, enforce some basic rules
* Make the Text element accessible by default
* Don't optimize away accessibility property in the LLR
* Ensure that accessibility property are marked as used
* Add some accessibility properties to the native style widgets
* Support for bool and integer `accessible` properties
* Implement basic support for accessibility
* Make basic widgets accessible by default
* Make slider focus-able and interactable with keyboard
* Tell a11y layer about value changes
* Generate QAccessible constants using bindgen
* Don't expose the `accessible` properties when using the MCU backend: There is no backend to make use of them
* Handle focus change based on keyboard focus of the window
* Report accessible widgets at correct positions
* Allow for (virtual) focus delegation at the a11y level
* Calculate value step size dynamically
* Make sure to not send notifications to a11y backend about dead objects
