Extracting an Event (tabControl_DrawItem) to Class Library

Question

I have the following code under a TabConttrols DrawItem event that I am trying to extract into a class file. I am having trouble since it is tied to an event. Any hints or pointers would be greatly appreciated.

        private void tabCaseNotes_DrawItem(object sender, DrawItemEventArgs e)
    {
        TabPage currentTab = tabCaseNotes.TabPages[e.Index];
        Rectangle itemRect = tabCaseNotes.GetTabRect(e.Index);
        SolidBrush fillBrush = new SolidBrush(Color.Linen);
        SolidBrush textBrush = new SolidBrush(Color.Black);
        StringFormat sf = new StringFormat
                              {
                                  Alignment = StringAlignment.Center,
                                  LineAlignment = StringAlignment.Center
                              };

        //If we are currently painting the Selected TabItem we'll
        //change the brush colors and inflate the rectangle.
        if (System.Convert.ToBoolean(e.State & DrawItemState.Selected))
        {
            fillBrush.Color = Color.LightSteelBlue;
            textBrush.Color = Color.Black;
            itemRect.Inflate(2, 2);
        }

        //Set up rotation for left and right aligned tabs
        if (tabCaseNotes.Alignment == TabAlignment.Left || tabCaseNotes.Alignment == TabAlignment.Right)
        {
            float rotateAngle = 90;
            if (tabCaseNotes.Alignment == TabAlignment.Left)
                rotateAngle = 270;
            PointF cp = new PointF(itemRect.Left + (itemRect.Width / 2), itemRect.Top + (itemRect.Height / 2));
            e.Graphics.TranslateTransform(cp.X, cp.Y);
            e.Graphics.RotateTransform(rotateAngle);
            itemRect = new Rectangle(-(itemRect.Height / 2), -(itemRect.Width / 2), itemRect.Height, itemRect.Width);
        }

        //Next we'll paint the TabItem with our Fill Brush
        e.Graphics.FillRectangle(fillBrush, itemRect);

        //Now draw the text.
        e.Graphics.DrawString(currentTab.Text, e.Font, textBrush, (RectangleF)itemRect, sf);

        //Reset any Graphics rotation
        e.Graphics.ResetTransform();

        //Finally, we should Dispose of our brushes.
        fillBrush.Dispose();
        textBrush.Dispose();
    }

Answer 1

Depends on what you're trying to achieve. You could always sub class TabControl or you could encapsulate the drawing code in a class that you pass a TabControl to.

public class TabRenderer
{
    private TabControl _tabControl;

    public TabRenderer(TabControl tabControl)
    {
        _tabControl = tabControl;
        _tabControl.DrawMode = TabDrawMode.OwnerDrawFixed;
        _tabControl.DrawItem += TabControlDrawItem;
    }

    private void TabControlDrawItem(object sender, DrawItemEventArgs e)
    {
     // Your drawing code...
    }
}