WPF InkCanvas 继承 class

Question

我想创建一个自定义 InkCanvas Adorner 并找到背后的逻辑：

You can re-use the existing lasso functionality of the InkCanvasEditingMode.Select mode. Then, in the SelectionChanged event, you can get a reference to the selected strokes (and/or elements). Now clear the selection (to get rid of the standard adorner) and then bring up your custom adorner.

我如何继承 InkCanvas class 我自己的编辑模式 class 并访问事件？

class myInkCanvasClass : InkCanvas ?
{
    base class constructor call ?
    ...

}

Answer 1

您不必继承 InkCanvas，SelectionChanged 是 InkCanvas 上的 public 事件，因此您只需向其添加处理程序即可。此外，EditingMode 是一个 public 属性，您也可以在 InkCanvas 的实例上设置它。因此，要将处理程序添加到 SelectionChanged 并在 Ink 和 Select 之间切换 EditingMode，您只需使用 public API 11=]实例。

基本示例：

inkCanvas.SelectionChanged += InkCanvas_SelectionChanged;
inkCanvas.EditingMode = InkCanvasEditingMode.Select;

Answer 2

我成功地将 InkCanvas Class 继承到我的 CustomInkCanvas Class 并获得了 SelectionChanged 的 EventListener：

public class CustomInkCanvas : InkCanvas
{
    //variables 

    //constructor
    public CustomInkCanvas()
    {
       //...
    }

    override protected void OnSelectionChanged(EventArgs e) 
    {
        MessageBox.Show("Selection Changed");
    }
}

因此，如果我更改选择，我会被注意到。

Answer 3

[DebuggerDisplay("[{Scene}]Strokes:{Strokes.Count}, Children:{Children.Count}")]
public class InkCanvas_Sandeep : InkCanvas
{
    public int PagId = -1;
    public InkCanvas_Sandeep()
    {
        DefaultDrawingAttributes.Color = Colors.Red;
        DefaultDrawingAttributes.FitToCurve = true;
        DefaultDrawingAttributes.Height = 2;
        DefaultDrawingAttributes.Width = 2;
        DefaultDrawingAttributes.IgnorePressure = false;
        DefaultDrawingAttributes.IsHighlighter = false;
        DefaultDrawingAttributes.StylusTip = System.Windows.Ink.StylusTip.Ellipse;
        DefaultDrawingAttributes.StylusTipTransform = Matrix.Identity;
        HorizontalAlignment = System.Windows.HorizontalAlignment.Stretch;
        VerticalAlignment = System.Windows.VerticalAlignment.Stretch;
        SnapsToDevicePixels = true;
    }
}
public void createMultipleInstances()
{
    InkCanvas_Sandeep canvas new InkCanvas_Sandeep();
    canvas.PagId = ++PageDetails.PageId;
}

WPF InkCanvas 继承 class

WPF InkCanvas inherit class

c#

wpf

inkcanvas