debugPrintBeginFrameBanner top-level property Null safety

Print a banner at the beginning of each frame.

Frames triggered by the engine and handler by the scheduler binding will have a banner giving the frame number and the time stamp of the frame.

Frames triggered eagerly by the widget framework (e.g. when calling runApp) will have a label saying "warm-up frame" instead of the time stamp (the time stamp sent to frame callbacks in that case is the time of the last frame, or 0:00 if it is the first frame).

To include a banner at the end of each frame as well, to distinguish intra-frame output from inter-frame output, set debugPrintEndFrameBanner to true as well.

See also:

• debugProfilePaintsEnabled, which does something similar for painting but using the timeline view.
• debugPrintLayouts, which does something similar for layout but using console output.
• The discussions at WidgetsBinding.drawFrame and at SchedulerBinding.handleBeginFrame.