A few problem:
- the horizontal and vertical property were swapped
- The implementation of the "preferred_xxx" property was not materialized properly
because the `bindings` were borrowed in the materialize_fake_properties pass
- Since the Window has a stretch factor of 0., the preferred size of the inner layout
was not taken into account when merging the LayoutInfo. I believe taking the
maximum preferred size is the right solution when merging them.
When using cmake to configure the C++ build and Qt is found, and then
build with `SIXTYFPS_NO_QT=0 cmake --build ..`, the C++ library is built
without Qt support but qt_viewer is built. Linkage then fails when it
tries to access the API in libsixtyfps_cpp.so that provides the QWidget,
as that symbol is not present.
So with newer CMake we use find_package to provide positive information
to the cargo build about where Qt is, and consequently this patch
provides negative information to disable Qt support if CMake could not
find Qt -- or it was deliberately disabled for example using
`-DCMAKE_DISABLE_FIND_PACKAGE_Qt5=1`.
cc #232
find_package(Qt5) may do a better job at finding qmake, especially if the build is invoked
through Qt Creator, which may make sure that CMAKE_PREFIX_PATH is set.
Forward the qmake path therefore the the rust build.
The item tree is intended to be initialized with pointers to the item
vtables, which are implemented using data relocation records that
resolve to the symbols exported by the sixtyfps_cpp shared library.
On windows, according to
https://docs.microsoft.com/en-us/cpp/c-language/rules-and-limitations-for-dllimport-dllexport?view=msvc-160
such data relocations are not supported, so this patch implements the
fallback through getter functions.
I can't seem to convince sphinx/breathe/doxygen to include them like
they work in the class docs.
I tried the markdown quotes, spaces, \code/\endcode, \rst/\endrst but no luck yet.
* 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.
Mark some functions as inline to avoid generating symbols that would
produce duplicate errors when linking multiple .o files that include the
SixtyFPS headers.
