"squishy" drag 'n' drop of pieces already on the board

[csells]

it feels like we're using touch-based d'n'd instead of mouse-based d'n'd which is intrinsically "squishy" as you have to move 5-10 pixels before a drag operation is registered and the piece is first moved.

[deniza]

@csells this is a general problem about Draggables. You can use a slightly modified version of Draggable to solve this issue. Below is a ZeroDelayDraggableClass I am using which prevents "touch -> drag" delay you mentioned.

class ZeroDelayDraggable extends Draggable<dynamic> {

  _ZeroDelayDraggable({Tile dynamic, int maxSimultaneousDrags, Widget child, Widget feedback, DragAnchor dragAnchor, Widget childWhenDragging, VoidCallback onDragStarted, DraggableCanceledCallback onDraggableCanceled, DragEndCallback onDragEnd})
    : super(data: data, maxSimultaneousDrags: maxSimultaneousDrags, child: child, feedback: feedback, dragAnchor: dragAnchor, childWhenDragging: childWhenDragging, onDragStarted: onDragStarted, onDraggableCanceled: onDraggableCanceled, onDragEnd: onDragEnd);

  @override
  MultiDragGestureRecognizer<MultiDragPointerState> createRecognizer(GestureMultiDragStartCallback onStart) {
    return DelayedMultiDragGestureRecognizer(delay: Duration.zero)..onStart = onStart;
  }

}

[csells]

Interesting. Can the same technique be used with a GestureDetector?

[deniza]

There will be a delay if you use multiple gesture recognizers on top of each other. Here we got 2 objects fighting for gesture events. One is game board, one is the draggable on the game board. If you have only one gesture detecting widget, for example a SingleChildScrollView, there will be no delay recognizing the drag gesture.