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// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
//
// Description:
// A class which is used as the feedback adorner of the InkCanvas selection
//
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Media;
namespace MS.Internal.Controls
{
/// <summary>
/// InkCanvasFeedbackAdorner
/// </summary>
internal class InkCanvasFeedbackAdorner : Adorner
{
// No default constructor
private InkCanvasFeedbackAdorner() : base(null) { }
/// <summary>
/// InkCanvasFeedbackAdorner Constructor
/// </summary>
/// <param name="inkCanvas">The adorned InkCanvas</param>
internal InkCanvasFeedbackAdorner(InkCanvas inkCanvas)
: base((inkCanvas != null ? inkCanvas.InnerCanvas : null))
{
ArgumentNullException.ThrowIfNull(inkCanvas);
// Initialize the internal data
_inkCanvas = inkCanvas;
_adornerBorderPen = new Pen(Brushes.Black, 1.0);
DoubleCollection dashes = new DoubleCollection();
dashes.Add(4.5);
dashes.Add(4.5);
_adornerBorderPen.DashStyle = new DashStyle(dashes, 2.25);
_adornerBorderPen.DashCap = PenLineCap.Flat;
}
/// <summary>
/// The overridden GetDesiredTransform method
/// </summary>
public override GeneralTransform GetDesiredTransform(GeneralTransform transform)
{
ArgumentNullException.ThrowIfNull(transform);
VerifyAccess();
GeneralTransformGroup desiredTransform = new GeneralTransformGroup();
desiredTransform.Children.Add(transform);
// Check if we need translate the adorner.
if (!DoubleUtil.AreClose(_offsetX, 0) || !DoubleUtil.AreClose(_offsetY, 0))
{
desiredTransform.Children.Add(new TranslateTransform(_offsetX, _offsetY));
}
return desiredTransform;
}
/// <summary>
/// The OnBoundsUpdated method
/// </summary>
/// <param name="rect"></param>
private void OnBoundsUpdated(Rect rect)
{
VerifyAccess();
// Check if the rectangle has been changed.
if (rect != _previousRect)
{
Size newSize;
double offsetX;
double offsetY;
bool invalidArrange = false;
if (!rect.IsEmpty)
{
double offset = BorderMargin + CornerResizeHandleSize / 2;
Rect adornerRect = Rect.Inflate(rect, offset, offset);
newSize = new Size(adornerRect.Width, adornerRect.Height);
offsetX = adornerRect.Left;
offsetY = adornerRect.Top;
}
else
{
newSize = new Size(0, 0);
offsetX = 0;
offsetY = 0;
}
// Check if the size has been changed
if (_frameSize != newSize)
{
_frameSize = newSize;
invalidArrange = true;
}
if (!DoubleUtil.AreClose(_offsetX, offsetX) || !DoubleUtil.AreClose(_offsetY, offsetY))
{
_offsetX = offsetX;
_offsetY = offsetY;
invalidArrange = true;
}
if (invalidArrange)
{
InvalidateMeasure();
InvalidateVisual(); //ensure re-rendering
UIElement parent = ((UIElement)VisualTreeHelper.GetParent(this)) as UIElement;
if (parent != null)
{
((UIElement)VisualTreeHelper.GetParent(this)).InvalidateArrange();
}
}
_previousRect = rect;
}
}
/// <summary>
/// The overridden MeasureOverride method
/// </summary>
/// <param name="constraint"></param>
protected override Size MeasureOverride(Size constraint)
{
VerifyAccess();
// return the frame size.
return _frameSize;
}
/// <summary>
/// The overridden OnRender method
/// </summary>
/// <param name="drawingContext"></param>
protected override void OnRender(DrawingContext drawingContext)
{
// No need to invoke VerifyAccess since this method calls DrawingContext.DrawRectangle.
Debug.Assert(_frameSize != new Size(0, 0));
// Draw the wire frame.
drawingContext.DrawRectangle(null, _adornerBorderPen,
new Rect(CornerResizeHandleSize / 2, CornerResizeHandleSize / 2,
_frameSize.Width - CornerResizeHandleSize, _frameSize.Height - CornerResizeHandleSize));
}
/// <summary>
/// The method is called by InkCanvasSelection.UpdateFeedbackRect
/// </summary>
/// <param name="rect"></param>
internal void UpdateBounds(Rect rect)
{
// Invoke OnBoundsUpdated.
OnBoundsUpdated(rect);
}
private InkCanvas _inkCanvas;
private Size _frameSize = new Size(0, 0);
private Rect _previousRect = Rect.Empty;
private double _offsetX = 0;
private double _offsetY = 0;
private Pen _adornerBorderPen;
private const int CornerResizeHandleSize = 8;
private const double BorderMargin = 8f;
}
}
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