C# Label highlight and remove highlight

Question

I'm sure this is something very easy to figure out but I cannot do it. I have a winform with 3 Label inside a Panel . When the form loads, the first Label has a Paint event that draws a rectangle on it. I would like a backgroundWorker to go through each one, wait 5 seconds, restore the Label to normal (redrawing I'm guessing) and then draw a rectangle on the following Label .

public List<Label> GetLabelList()
        {
            return new List<List>()
            {
                label1,
                label2,
                label3,
                label4
            };
        }

private void bgBackgroundWorker_DoWork(object sender, DoWorkEventArgs e)
    {
        var getList = GetLabelList();

        for (int i = 0; i < getList.Count; i++)
        {
            if ((bgBackgroundWorker.CancellationPending == true))
            {
                e.Cancel = true;
                break;
            }

            else
            {
                Thread.Sleep(5000);
                getList [i].Paint += RemoveLabelHighlight;
                getList [i].Invalidate();

                if (i < 2)
                {
                    getList [i + 1].Paint += AddLabelHighlight;
                    getList [i + 1].Invalidate();
                }

                bgBackgroundWorker.ReportProgress((i * 10));
            }
        }
    }

private void AddLabelHighlight(object sender, PaintEventArgs e)
    {
        var label = sender as Label;
        e.Graphics.DrawRectangle(new Pen(Color.DeepPink, 8), label.ClientRectangle);
    }

    private void RemoveLabelHighlight(object sender, PaintEventArgs e)
    {
        var label = sender as Label; 
        e.Graphics.DrawRectangle(new Pen(Color.Green, 8), label.ClientRectangle); // This should return the Label back to original state
    }

This works but when the rectangle is drawn, the label is cut off all the way around. Any suggestions?

Also, I'm sure there is a much better and more efficient way to achieve this, maybe by an EventHandler or something. I'd like some suggestions, if possible.

Answer 1

This is actually being caused by your use of the pen width of 8 pixels, I believe. Try a different size and see if that changes the size of the rectangle not being drawn.

To fill the rectangle instead, use:

e.Graphics.FillRectangle(new SolidBrush(Color.DeepPink), e.ClipRectangle);

EDIT Since you're now completely responsible for drawing the control, the text can be redrawn with a DrawString call:

e.Graphics.DrawString(label.Text, label.Font, SystemBrushes.ControlText, new PointF(0,0));

EDIT Here's how to nest a panel and a label to achieve what you're looking for:

• Add a new panel, set the padding to 8,8,8,8, and BackColor to whatever you like
• Add a new label to this panel, set it's AutoSize property to false, Dock property to Fill, and TextAlign property to MiddleCenter

While I have always loved doing owner-drawn stuff, sometimes it's just easier to use what's there! For fun though, I would wrap this into a new Panel-derived control to make it easy to reuse.