Hello!
A have a custom GridLayout class:
`using System;
using Android.Widget;
using Android.Content;
using Android.Graphics;

namespace SUDOKU
{
public class GridLayoutExt:GridLayout
{
public GridLayoutExt (Context context):base(context)
{
SetWillNotDraw (false);
}

    protected override void OnDraw(Canvas canvas)
    {
        base.OnDraw (canvas);

        Paint paint = new Paint ();
        paint.Color = Android.Graphics.Color.Red;
        paint.StrokeWidth = 4;

        canvas.DrawLine (0, 0, 100, 100, paint);

    }
}

}`

How can I add it to the screen of my application&

When I'm trying to start application I have an exception:
java.lang.reflect.InvocationTargetException

In this place:
GridLayoutExt GL = new GridLayoutExt (this); GL.ColumnCount = ColNum; **GL.LayoutParameters.Width = getWidth();** GL.LayoutParameters.Height = getWidth();

Here is the getWidth() method:

`public int getWidth()
{
int widthInP;
var metrics = Resources.DisplayMetrics;
widthInP = metrics.WidthPixels;//ConvertPixelsToDp(metrics.WidthPixels);

        return widthInP;
    }`

How can I resolve this problem?
Thank you for help!