isDismissible property
A flag indicating whether the flushbar can be dismissed.
If set to true, the flushbar can be dismissed by the user. The dismiss
action can be triggered by swiping in the direction specified by
dismissDirection, or by tapping on the flushbar if onTap is provided.
If set to false, the flushbar will not be dismissible, and user actions
such as swiping or tapping will have no effect.
The default value is true.
Implementation
final bool isDismissible;