onTriggered property
final
Called when an undo or redo causes a state change.
If the state would still be the same before and after the undo/redo, this will not be called. For example, receiving a redo when there is nothing to redo will not call this method.
Changes to the value while this method is running will not be recorded on the undo stack. For example, a TextInputFormatter may change the value from what was on the undo stack, but this new value will not be recorded, as that would wipe out the redo history.
Implementation
final void Function(T value) onTriggered;