WPF InkCanvas inherit class

Question

I want to create an custom InkCanvas Adorner and found the logic behind:

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.

How can i inherit the InkCanvas class with the editing mode in my own class and get access to the Events?

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

}

Answer 1

You shouldn't have to inherit from InkCanvas , SelectionChanged is a public event on InkCanvas so you can just add a handler to it. Also the EditingMode is a public property that you can set on an instance of InkCanvas as well. So to add the handler to SelectionChanged and toggle the EditingMode between Ink and Select you can just use the public API of an InkCanvas instance.

Basic example:

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

Answer 2

I managed to inherit the InkCanvas Class to my CustomInkCanvas Class and get the EventListener of SelectionChanged:

public class CustomInkCanvas : InkCanvas
{
    //variables 

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

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

So if i change a Selection i get noticed.

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;
}