QWidget: Don't re-use backing store on Android

QWidget re-uses backing stores created in QWidgetPrivate::create().
The Android platform plugin creates a new platform window, when a
widget becomes a toplevel window. When it is hidden, the platform
window is deleted. The link between QAndroidPlatformWindow and its
backing store is made in the constructor of
QAndroidPlatformBackingstore. When a new QAndroidPlatformWindow is
constructed and the backing store is re-used, there is no more link
between platform window and platform backing store.
This has lead to screen assets not being painted, when shown more than
once.

This patch forces QWidgetPrivate::create() to construct a new backing
store on Android. This way, toplevel windows always have a backing
store associated with it. It adds an assertion to
QAndroidPlatformScreen::addWindow(). That will make e.g.
tst_QWidget::visible() crash without the fix.

Fixes: QTBUG-97482
Pick-to: 6.6 6.5 6.2
Change-Id: Ib1b172068b03549df161ab93ac24a273221d5423
Reviewed-by: Jan Arve Sæther <jan-arve.saether@qt.io>

0 files changed, 0 insertions, 0 deletions