touchEventToMouseEvent function

MouseEvent? touchEventToMouseEvent(TouchEvent event)

Converts a TouchEvent event to a MouseEvent.

This helps to use TouchEvent as normal MouseEvent, simplifying UI support for touch events and mouse events.

Implementation

MouseEvent? touchEventToMouseEvent(TouchEvent event) {
  var touches = event.touches;
  if (touches == null || touches.isEmpty) return null;

  var first = touches[0];
  var type = '';

  switch (event.type.toLowerCase()) {
    case 'touchstart':
      type = 'mousedown';
      break;
    case 'touchmove':
      type = 'mousemove';
      break;
    case 'touchend':
      type = 'mouseup';
      break;
    default:
      return null;
  }

  EventTarget? target;

  // If `event.target` is null, not dispatched, it will throw an exception.
  try {
    target = event.target;
  }
  // ignore: empty_catches
  catch (ignore) {}

  var simulatedEvent = MouseEvent(type,
      canBubble: event.bubbles!,
      cancelable: event.cancelable!,
      view: window,
      detail: 1,
      screenX: first.screen.x as int,
      screenY: first.screen.y as int,
      clientX: first.client.x as int,
      clientY: first.client.y as int,
      ctrlKey: event.ctrlKey!,
      altKey: event.altKey!,
      shiftKey: event.shiftKey!,
      metaKey: event.metaKey!,
      button: 0,
      relatedTarget: target);

  return simulatedEvent;
}