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Aligning text in OwnerDraw tooltip in C # /. NET

I have a multi-line text string (eg "Stuff \ nMore Stuff \ nYet More Stuff") and I want to draw it along with the bitmap in the tooltip. Since I am drawing a bitmap I need to set OwnerDraw to true, which is what I do. I also handle the Popup event, so I can tweak the tooltip just enough to hold the text and bitmap.

I call e.DrawBackground and e.DrawBorder () and then draw a bitmap on the left side of the tooltip area.

Is there a set of flags that I can pass to e.DrawText () to align the text to the left, but offset it so that it doesn't draw on top of my bitmap? Or do I need the custom to draw all the text (which would probably involve splitting the line into newlines, etc.)?

UPDATED: The final code looks like this:

private void _ItemTip_Draw(object sender, DrawToolTipEventArgs e)
{
  e.DrawBackground();
  e.DrawBorder();

  // Reserve a square of size e.Bounds.Height x e.Bounds.Height
  // for the image. Keep a margin around it so that it looks good.
  int margin = 2;
  Image i = _ItemTip.Tag as Image;  
  if (i != null)
  {
    int side = e.Bounds.Height - 2 * margin;  
    e.Graphics.DrawImage(i, new Rectangle(margin, margin, side, side));
  }

  // Construct bounding rectangle for text (don't want to paint it over the image).
  int textOffset = e.Bounds.Height + 2 * margin; 
  RectangleF rText = e.Bounds;
  rText.Offset(textOffset, 0);
  rText.Width -= textOffset;

  e.Graphics.DrawString(e.ToolTipText, e.Font, Brushes.Black, rText);
}
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2 answers


My guess is that if you define a bounding box to draw (calculating the image offset yourself), you can simply:



     RectangleF rect = new RectangleF(100,100,100,100);
     e.Graphics.DrawString(myString, myFont, myBrush, rect);
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to calculate the height of the owner, drawn on line s with a specific width w, we use the following code:

double MeasureStringHeight (Graphics g, string s, Font f, int w) {
    double result = 0;
    int n = s.Length;
    int i = 0;
    while (i < n) {
        StringBuilder line = new StringBuilder();
        int iLineStart = i;
        int iSpace = -1;
        SizeF sLine = new SizeF(0, 0);
        while ((i < n) && (sLine.Width <= w)) {
            char ch = s[i];
            if ((ch == ' ') || (ch == '-')) {
                iSpace = i;
            }
            line.Append(ch);
            sLine = g.MeasureString(line.ToString(), f);
            i++;
        }
        if (sLine.Width > w) {
            if (iSpace >= 0) {
                i = iSpace + 1;
            } else {
                i--;
            }
            // Assert(w > largest ch in line)
        }
        result += sLine.Height;
    }
    return result;
}


Regards, Tamberg

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