How to: Custom Paint Hints

  • 2 minutes to read

The sample code below handles the NavBarControl.CustomDrawHint event to custom paint hints in the VSToolBoxView style. The NavBarControl.CalcHintSize event is handled to adjust the size of the hints in order to draw their outer borders.

The image below shows the result.

CustomDraw - Hints

using System.Drawing.Drawing2D;

private void navBarControl1_CalcHintSize(object sender, NavBarCalcHintSizeEventArgs e)
{
    // Enlarge the size of the hint to create space for drawing borders
    Size NewSize = e.Size;
    NewSize.Width += 18;
    NewSize.Height += 8;
    e.Size = new Size(NewSize.Width, NewSize.Height);
}

private void navBarControl1_CustomDrawHint(object sender, NavBarCustomDrawHintEventArgs e)
{
    // Obtain the object used to paint.
    Graphics gr = e.PaintArgs.Graphics;

    // Paint borders.
    LinearGradientBrush outerBrush = new LinearGradientBrush(e.Bounds, 
        Color.LightSkyBlue, Color.Blue, LinearGradientMode.Vertical);
    gr.FillRectangle(outerBrush, e.Bounds);
    outerBrush.Dispose();

    // Paint the background.
    // The background rectangle is reduced to make the borders visible.
    Rectangle innerRect = Rectangle.Inflate(e.Bounds, -3, -3);
    LinearGradientBrush innerBrush = new LinearGradientBrush(e.Bounds, 
        Color.Blue, Color.LightSkyBlue, LinearGradientMode.Vertical);
    gr.FillRectangle(innerBrush, innerRect);
    innerBrush.Dispose();

    // Format the output string.
    RectangleF textRect = new RectangleF(innerRect.Left, innerRect.Top, 
        innerRect.Width, innerRect.Height);
    StringFormat outStringFormat = new StringFormat();
    outStringFormat.Alignment = StringAlignment.Center;
    outStringFormat.LineAlignment = StringAlignment.Center;

    // Paint text.
    SolidBrush textBrush = new SolidBrush(Color.White);
    gr.DrawString(e.Hint, e.Appearance.Font, textBrush, textRect, outStringFormat);
    textBrush.Dispose();

    // Prohibit default hint painting         
    e.Handled = true;
}