/// <summary>
/// Tunneled event handler for when the mouse is moving
/// </summary>
/// <param name="sender">The object which invokes this event</param>
/// <param name="e">Event args from the sender</param>
private void DragSource_PreviewMouseMove(Object sender, MouseEventArgs e)
{
if (_mouseCaptured || _dragDropPreviewControlDataContext == null)
{
return; //we're already capturing the mouse, or we don't have a data context for the preview control
}
if (DragDrop.IsMovementBigEnough(_initialMousePosition, e.GetPosition(_topWindow)) == false)
{
return; //only drag when the user moved the mouse by a reasonable amount
}
_dragDropPreviewControl = (DragDropPreviewBase)GetDragDropPreviewControl(sender as DependencyObject);
_dragDropPreviewControl.DataContext = _dragDropPreviewControlDataContext;
_dragDropPreviewControl.Opacity = 0.7;
_dragDropContainer.Children.Add(_dragDropPreviewControl);
_mouseCaptured = Mouse.Capture(_dragDropPreviewControl); //have the preview control recieve and be able to handle mouse events
//offset it just a bit so it looks like it's underneath the mouse
Mouse.OverrideCursor = Cursors.Hand;
Canvas.SetLeft(_dragDropPreviewControl, _initialMousePosition.X - 20);
Canvas.SetTop(_dragDropPreviewControl, _initialMousePosition.Y - 15);
_dragDropContainer.PreviewMouseMove += DragDropContainer_PreviewMouseMove;
_dragDropContainer.PreviewMouseUp += DragDropContainer_PreviewMouseUp;
}
/// <summary>
/// Removes the drag and drop preview control from the drag drop canvas, and clears the reference for the next drag/drop operation
/// </summary>
private void FinalizePreviewControlMouseUp()
{
_dragDropContainer.Children.Remove(_dragDropPreviewControl);
_dragDropContainer.PreviewMouseMove -= DragDropContainer_PreviewMouseMove;
_dragDropContainer.PreviewMouseUp -= DragDropContainer_PreviewMouseUp;
if (_dragDropPreviewControl != null)
{
_dragDropPreviewControl.ReleaseMouseCapture();
}
_dragDropPreviewControl = null;
Mouse.OverrideCursor = null;
}
/// <summary>
/// Removes the drag and drop preview control from the drag drop canvas, and clears the reference for the next drag/drop operation
/// </summary>
private void FinalizePreviewControlMouseUp()
{
_dragDropContainer.Children.Remove(_dragDropPreviewControl);
_dragDropContainer.PreviewMouseMove -= DragDropContainer_PreviewMouseMove;
_dragDropContainer.PreviewMouseUp -= DragDropContainer_PreviewMouseUp;
if (_dragDropPreviewControl != null)
{
_dragDropPreviewControl.ReleaseMouseCapture();
}
_dragDropPreviewControl = null;
Mouse.OverrideCursor = null;
}
/// <summary>
/// Tunneled event handler for when the mouse is moving
/// </summary>
/// <param name="sender">The object which invokes this event</param>
/// <param name="e">Event args from the sender</param>
private void DragSource_PreviewMouseMove(Object sender, MouseEventArgs e)
{
if (_mouseCaptured || _dragDropPreviewControlDataContext == null)
{
return; //we're already capturing the mouse, or we don't have a data context for the preview control
}
if (DragDrop.IsMovementBigEnough(_initialMousePosition, e.GetPosition(_topWindow)) == false)
{
return; //only drag when the user moved the mouse by a reasonable amount
}
_dragDropPreviewControl = (DragDropPreviewBase)GetDragDropPreviewControl(sender as DependencyObject);
_dragDropPreviewControl.DataContext = _dragDropPreviewControlDataContext;
_dragDropPreviewControl.Opacity = 0.7;
_dragDropContainer.Children.Add(_dragDropPreviewControl);
_mouseCaptured = Mouse.Capture(_dragDropPreviewControl); //have the preview control recieve and be able to handle mouse events
//offset it just a bit so it looks like it's underneath the mouse
Mouse.OverrideCursor = Cursors.Hand;
Canvas.SetLeft(_dragDropPreviewControl, _initialMousePosition.X - 20);
Canvas.SetTop(_dragDropPreviewControl, _initialMousePosition.Y - 15);
_dragDropContainer.PreviewMouseMove += DragDropContainer_PreviewMouseMove;
_dragDropContainer.PreviewMouseUp += DragDropContainer_PreviewMouseUp;
}
/// <summary>
/// Sets the attached value of <see cref="DragDropPreviewControlProperty"/>
/// </summary>
/// <param name="element">The <see cref="DependencyObject"/> that the attached <see cref="DependencyProperty"/>, <see cref="DragDropPreviewControlProperty"/>, is attched to.</param>
/// <param name="value">the value to set</param>
public static void SetDragDropPreviewControl(DependencyObject element, DragDropPreviewBase value)
{
element.SetValue(DragDropPreviewControlProperty, value);
}
/// <summary>
/// Sets the attached value of <see cref="DragDropPreviewControlProperty"/>
/// </summary>
/// <param name="element">The <see cref="DependencyObject"/> that the attached <see cref="DependencyProperty"/>, <see cref="DragDropPreviewControlProperty"/>, is attched to.</param>
/// <param name="value">the value to set</param>
public static void SetDragDropPreviewControl(DependencyObject element, DragDropPreviewBase value)
{
element.SetValue(DragDropPreviewControlProperty, value);
}