Implements the debugPaintPointersEnabled
debugging feature.
RenderBox
subclasses that implement handleEvent
should call
debugHandleEvent
from their handleEvent
method, as follows:
@override
void handleEvent(PointerEvent event, HitTestEntry entry) {
assert(debugHandleEvent(event, entry));
// ... handle the event ...
}
If you call this for a PointerDownEvent
, make sure you also call it for
the corresponding PointerUpEvent
or PointerCancelEvent
.
Source
bool debugHandleEvent(PointerEvent event, HitTestEntry entry) { assert(() { if (debugPaintPointersEnabled) { if (event is PointerDownEvent) { _debugActivePointers += 1; } else if (event is PointerUpEvent || event is PointerCancelEvent) { _debugActivePointers -= 1; } markNeedsPaint(); } return true; }); return true; }