animatedAppearing property
If true, the panel is created (instantiated) with PanelState.dismissed. After initialization is completed, the panel animates to given initialState.
Useful when navigating to a new route, that contains an open SlidingPanel.
For modal panels, this is ignored, as they always animate while created.
NOTE that this value can't be changed once the panel is created.
Default : false
Implementation
final bool animatedAppearing;