c# - Drag selection box in WPF

Question

Is it possible to implement mouse hover selection by hover on the object and drawing a circle and drag selection hover box in WPF. what I want specifically when the user hover on the button a by drawing a circle this button make specific action like as click on it. Could you give a bit of sample code or a link?

Answer 1

It is an advanced topic and involves the use of adorners More information can be found here :

https://denisvuyka.wordpress.com/2007/10/15/wpf-simple-adorner-usage-with-drag-and-resize-operations/

and

What's the point to WPF adorners?

A small example where I used it :

public class SelectionAdorner : Adorner
{
    public SelectionAdorner(UIElement adornedElement)
        : base(adornedElement)
    {
    }

    protected override void OnRender(DrawingContext drawingContext)
    {
        Rect adornedElementRect = new Rect(0,0,ActualWidth,ActualHeight);

        // Some arbitrary drawing implements.
        SolidColorBrush renderBrush = new SolidColorBrush(Colors.Green);
        renderBrush.Opacity = 0.2;
        Pen renderPen = new Pen(new SolidColorBrush(Colors.Navy), 1.5);
        double renderRadius = 5.0;

        // Draw a circle at each corner.
        drawingContext.DrawEllipse(renderBrush, renderPen, adornedElementRect.TopLeft, renderRadius, renderRadius);
        drawingContext.DrawEllipse(renderBrush, renderPen, adornedElementRect.TopRight, renderRadius, renderRadius);
        drawingContext.DrawEllipse(renderBrush, renderPen, adornedElementRect.BottomLeft, renderRadius, renderRadius);
        drawingContext.DrawEllipse(renderBrush, renderPen, adornedElementRect.BottomRight, renderRadius, renderRadius);
    }

}