/// <summary>
/// Assigns an event handler to capture mouse events.
/// </summary>
/// <param name="handler">The event handler that captures mouse events.</param>
/// <remarks>
/// If an event handler is already set to capture mouse events, the event handler is replaced with the handler specified by this method.
/// </remarks>
public static void CaptureMouse(this IEventHandler handler)
{
VisualElement ve = handler as VisualElement;
if (ve != null)
{
ve.CapturePointer(PointerId.mousePointerId);
ve.panel.ProcessPointerCapture(PointerId.mousePointerId);
}
}
public static void CaptureMouse(this IEventHandler handler)
{
VisualElement visualElement = handler as VisualElement;
bool flag = visualElement != null;
if (flag)
{
visualElement.CapturePointer(PointerId.mousePointerId);
visualElement.panel.ProcessPointerCapture(PointerId.mousePointerId);
}
}
private void OnPointerMoveEvent(PointerMoveEvent evt)
{
if (useDragEvents)
{
if (m_DragState != DragState.CanStartDrag)
{
return;
}
}
else
{
if (m_DragState == DragState.Dragging)
{
UpdateDrag(evt.position);
return;
}
if (m_DragState != DragState.CanStartDrag)
{
return;
}
}
if (Mathf.Abs(m_Start.x - evt.position.x) > k_DistanceToActivation ||
Mathf.Abs(m_Start.y - evt.position.y) > k_DistanceToActivation)
{
var startDragArgs = StartDrag(m_Start);
if (useDragEvents)
{
// Drag can only be started by mouse events or else it will throw an error, so we leave early.
if (Event.current.type != EventType.MouseDown && Event.current.type != EventType.MouseDrag)
{
return;
}
DragAndDropUtility.dragAndDrop.StartDrag(startDragArgs);
}
else // Force default drag and drop client for runtime panels.
{
m_Target.CapturePointer(evt.pointerId);
evt.StopPropagation();
dragAndDropClient = new DefaultDragAndDropClient();
dragAndDropClient.StartDrag(startDragArgs);
}
m_DragState = DragState.Dragging;
}
}
private void UpdateValueOnPointerDown(PointerDownEvent evt)
{
if (CanStartDrag(evt.button, evt.localPosition))
{
// We want to allow dragging when using a mouse in any context and when in an Editor context with any pointer type.
if (evt.pointerType == PointerType.mouse)
{
m_DragElement.CaptureMouse();
ProcessDownEvent(evt);
}
else if (m_DragElement.panel.contextType == ContextType.Editor)
{
evt.PreventDefault();
m_DragElement.CapturePointer(evt.pointerId);
ProcessDownEvent(evt);
}
}
}