onNeedVisualUpdate property Null safety

VoidCallback? onNeedVisualUpdate
final

Called when a render object associated with this pipeline owner wishes to update its visual appearance.

Typical implementations of this function will schedule a task to flush the various stages of the pipeline. This function might be called multiple times in quick succession. Implementations should take care to discard duplicate calls quickly.

Implementation

final VoidCallback? onNeedVisualUpdate;