Flutter for Beginners

Horizontal drag

Let's see how the horizontal version looks in code:

// part of drag_event_example.dart (full source code in the attached files)GestureDetector(  onHorizontalDragStart: (DragStartDetails details) {    setState(() {      _move = Offset.zero;      _dragging = true;     });  },  onHorizontalDragUpdate: (DragUpdateDetails details) {    setState(() {      _move += details.delta;    });  },  onHorizontalDragEnd: (DragEndDetails details) {    setState(() {       _dragging = false;      _dragCount++;    });  },  child: ... // for brevity)

This time, we need a bit more work than for tap events. In the example, we have three properties present in the state:

• _dragging: Used to update the text viewed by the user while dragging.
• _dragCount: This accumulates the total number of drag events ...