User handles in Xamarin.Android diagram

14 Oct 20223 minutes to read

User handles are customizable handles which can be used to perform custom actions and also default clipboard actions. You can able to customize the user handles using:

• SfGraphicPath
• Image
• View

The following code illustrates how to add custom user handle in diagram:

C#

//Add graphic path into user handle
SfGraphics graph = new SfGraphics();
Pen stroke = new Pen();
stroke.Brush = new SolidBrush(Color.Transparent);
stroke.StrokeWidth = 3;
stroke.StrokeBrush = new SolidBrush(Color.Rgb(24, 161, 237));
graph.DrawEllipse(stroke, new System.Drawing.Rectangle(10, 0, 20, 20));
graph.DrawArc(stroke, 0, 20, 40, 40, 180, 180);
diagram.UserHandles.Add(new Syncfusion.SfDiagram.Android.UserHandle("SfGraphicsPath", UserHandlePosition.Right, graph) { BackgroundColor = Color.Transparent });

//Add image into user handle
var image = new ImageView(this);
image.SetImageResource(Resource.Drawable.delete);
diagram.UserHandles.Add(new Syncfusion.SfDiagram.Android.UserHandle("Delete", UserHandlePosition.Bottom, image));

//Add View into user handle
var view = new View(this);
view.SetBackgroundColor(Color.Purple);
diagram.UserHandles.Add(new Syncfusion.SfDiagram.Android.UserHandle("View", UserHandlePosition.Left, view));

User handles clicked event

The following code illustrate how to define user handles clicked event and its action.

C#

//User handles clicked event
diagram.UserHandleClicked += Diagram_UserHandleClicked;

private void Diagram_UserHandleClicked(object sender, UserHandleClickedEventArgs args)
{
    if (args.Item.Name == "Delete")
    {
        diagram.Delete();
    }
}

Customizing user handle position

User handle position can be moved or adjusted from its default position. The following code shows how to adjust the position using the “MoveBy” method.

C#

//Define the user handle 

            UserHandleCollection userHandles = new UserHandleCollection();
            UserHandle left = new UserHandle("Left", UserHandlePosition.Left, plusTemplate) { Visible = true };
     //Customize the user handle position using move by method
            left.MoveBy(-10, -10);
            userHandles.Add(left);
            userHandles.Add(new UserHandle("Right", UserHandlePosition.Right, m_expandTemplate) { Visible = true });
            userHandles.Add(new UserHandle("Delete", UserHandlePosition.Bottom, deleteTemplate) { Visible = true });
            diagram.UserHandles = userHandles;