/// <summary>
/// Event raised on mouse down in the ZoomAndPanControl.
/// </summary>
protected override void OnMouseDown(MouseButtonEventArgs e)
{
base.OnMouseLeftButtonDown(e);
GetZoomAndPanControl().SaveZoom();
_mouseHandlingMode = MouseHandlingModeEnum.Panning;
_origContentMouseDownPoint = e.GetPosition(_viewportCanvas);
if ((Keyboard.Modifiers & ModifierKeys.Shift) != 0)
{
// Shift + left- or right-down initiates zooming mode.
_mouseHandlingMode = MouseHandlingModeEnum.DragZooming;
_dragBorder.Visibility = Visibility.Hidden;
_sizingBorder.Visibility = Visibility.Visible;
Canvas.SetLeft(_sizingBorder, _origContentMouseDownPoint.X);
Canvas.SetTop(_sizingBorder, _origContentMouseDownPoint.Y);
_sizingBorder.Width = 0;
_sizingBorder.Height = 0;
}
else
{
// Just a plain old left-down initiates panning mode.
_mouseHandlingMode = MouseHandlingModeEnum.Panning;
}
if (_mouseHandlingMode != MouseHandlingModeEnum.None)
{
// Capture the mouse so that we eventually receive the mouse up event.
_viewportCanvas.CaptureMouse();
e.Handled = true;
}
}
/// <summary>
/// Event raised on mouse down in the ZoomAndPanControl.
/// </summary>
protected override void OnMouseDown(MouseButtonEventArgs e)
{
base.OnMouseDown(e);
SaveZoom();
_content.Focus();
Keyboard.Focus(_content);
_mouseButtonDown = e.ChangedButton;
_origZoomAndPanControlMouseDownPoint = e.GetPosition(this);
_origContentMouseDownPoint = e.GetPosition(_content);
if ((Keyboard.Modifiers & ModifierKeys.Shift) != 0 &&
(e.ChangedButton == MouseButton.Left ||
e.ChangedButton == MouseButton.Right))
{
// Shift + left- or right-down initiates zooming mode.
_mouseHandlingMode = MouseHandlingModeEnum.Zooming;
}
else if (_mouseButtonDown == MouseButton.Left)
{
// Just a plain old left-down initiates panning mode.
_mouseHandlingMode = MouseHandlingModeEnum.Panning;
}
if (_mouseHandlingMode != MouseHandlingModeEnum.None)
{
// Capture the mouse so that we eventually receive the mouse up event.
this.CaptureMouse();
}
}
/// <summary>
/// Event raised on mouse up in the ZoomAndPanControl.
/// </summary>
protected override void OnMouseUp(MouseButtonEventArgs e)
{
base.OnMouseUp(e);
if (_mouseHandlingMode != MouseHandlingModeEnum.None)
{
if (_mouseHandlingMode == MouseHandlingModeEnum.Zooming)
{
if (_mouseButtonDown == MouseButton.Left)
{
// Shift + left-click zooms in on the content.
ZoomIn(_origContentMouseDownPoint);
}
else if (_mouseButtonDown == MouseButton.Right)
{
// Shift + left-click zooms out from the content.
ZoomOut(_origContentMouseDownPoint);
}
}
else if (_mouseHandlingMode == MouseHandlingModeEnum.DragZooming)
{
var finalContentMousePoint = e.GetPosition(_content);
// When drag-zooming has finished we zoom in on the rectangle that was highlighted by the user.
ApplyDragZoomRect(finalContentMousePoint);
}
this.ReleaseMouseCapture();
_mouseHandlingMode = MouseHandlingModeEnum.None;
}
}
/// <summary>
/// Event raised on mouse move in the ZoomAndPanControl.
/// </summary>
protected override void OnMouseMove(MouseEventArgs e)
{
base.OnMouseMove(e);
var oldContentMousePoint = MousePosition;
var curContentMousePoint = e.GetPosition(_content);
MousePosition = curContentMousePoint.FilterClamp(_content.ActualWidth - 1, _content.ActualHeight - 1);
OnPropertyChanged(new DependencyPropertyChangedEventArgs(MousePositionProperty, oldContentMousePoint,
curContentMousePoint));
if (_mouseHandlingMode == MouseHandlingModeEnum.Panning)
{
//
// The user is left-dragging the mouse.
// Pan the viewport by the appropriate amount.
//
var dragOffset = curContentMousePoint - _origContentMouseDownPoint;
this.ContentOffsetX -= dragOffset.X;
this.ContentOffsetY -= dragOffset.Y;
e.Handled = true;
}
else if (_mouseHandlingMode == MouseHandlingModeEnum.Zooming)
{
var curZoomAndPanControlMousePoint = e.GetPosition(this);
var dragOffset = curZoomAndPanControlMousePoint - _origZoomAndPanControlMouseDownPoint;
double dragThreshold = 10;
if (_mouseButtonDown == MouseButton.Left &&
(Math.Abs(dragOffset.X) > dragThreshold ||
Math.Abs(dragOffset.Y) > dragThreshold))
{
//
// When Shift + left-down zooming mode and the user drags beyond the drag threshold,
// initiate drag zooming mode where the user can drag out a rectangle to select the area
// to zoom in on.
//
_mouseHandlingMode = MouseHandlingModeEnum.DragZooming;
InitDragZoomRect(_origContentMouseDownPoint, curContentMousePoint);
}
}
else if (_mouseHandlingMode == MouseHandlingModeEnum.DragZooming)
{
//
// When in drag zooming mode continously update the position of the rectangle
// that the user is dragging out.
//
curContentMousePoint = e.GetPosition(this);
SetDragZoomRect(_origZoomAndPanControlMouseDownPoint, curContentMousePoint);
}
}
/// <summary>
/// Event raised on mouse up in the ZoomAndPanControl.
/// </summary>
protected override void OnMouseUp(MouseButtonEventArgs e)
{
base.OnMouseLeftButtonUp(e);
if (_mouseHandlingMode == MouseHandlingModeEnum.DragZooming)
{
var zoomAndPanControl = GetZoomAndPanControl();
var curContentPoint = e.GetPosition(_viewportCanvas);
var rect = ViewportHelpers.Clip(curContentPoint, _origContentMouseDownPoint, new Point(0, 0),
new Point(_viewportCanvas.Width, _viewportCanvas.Height));
zoomAndPanControl.AnimatedZoomTo(rect);
_dragBorder.Visibility = Visibility.Visible;
_sizingBorder.Visibility = Visibility.Hidden;
}
_mouseHandlingMode = MouseHandlingModeEnum.None;
_viewportCanvas.ReleaseMouseCapture();
e.Handled = true;
}
