Question

How can I disable the focus cues on a SplitContainer?
I ask because I’d rather draw them myself using OnPaint in order to make it look somewhat smoother.

I tried this:

    protected override bool ShowFocusCues
    {
        get
        {
            return false;
        }
    }

And this is my control:

    public class cSplitContainer : SplitContainer
    {
        private bool IsDragging;

        protected override void OnMouseDown(MouseEventArgs e)
        {
            base.OnMouseDown(e);
            if (!IsSplitterFixed) IsDragging = true;
            Invalidate();
        }
        protected override void OnMouseUp(MouseEventArgs e)
        {
            base.OnMouseUp(e);
            if (IsDragging)
            {
                IsDragging = false;
                IsSplitterFixed = false;
            }
        }
        protected override void OnMouseMove(MouseEventArgs e)
        {
            base.OnMouseMove(e);
            if (IsDragging)
            {
                IsSplitterFixed = true;
                if (e.Button == MouseButtons.Left)
                {
                    if (Orientation == Orientation.Vertical)
                    {
                        if (e.X > 0 && e.X < Width) SplitterDistance = e.X;
                    }
                    else
                    {
                        if (e.Y > 0 && e.Y < Height) SplitterDistance = e.Y;
                    }
                }
                else
                {
                    IsDragging = false;
                    IsSplitterFixed = false;
                }
            }
        }
        protected override void OnPaint(System.Windows.Forms.PaintEventArgs e)
        {
            base.OnPaint(e);
            if (IsDragging)
            {
                e.Graphics.FillRectangle(new SolidBrush(Color.FromArgb(127, 0, 0, 0)), Orientation == Orientation.Horizontal ? new Rectangle(0, SplitterDistance, Width, SplitterWidth) : new Rectangle(SplitterDistance, 0, SplitterWidth, Height));
            }
        }
    }

but it didn’t work. I also tried some other methods mentioned before, but I’m still getting focus cues.

Answer 1

The code of SplitContainer is like:

protected override void OnPaint(PaintEventArgs e) {
  base.OnPaint(e);
  if (Focused) {
    DrawFocus(e.Graphics,SplitterRectangle);
  }
}

DrawFocus is not virtual. So you can’t override it.
Focused is virtual. Maybe you can set it to false while calling base.OnPaint(...) in your OnPaint override.

So you could add following code (I did not tested if it works):

private bool _painting;
public override bool Focused
{
  get { return _painting ? false : base.Focused; }
}

protected override void OnPaint(PaintEventArgs e)
{
  _painting = true;

  try
  {
    base.OnPaint(e);
  }
  finally
  {
    _painting = false;
  }
}

That is more a hack than a clean solution.