GDI Font

[Administrator]

It appears that when using the GridGdiPaint method that the facename of the font is not being used. In the attached example, cell A1 is being set to some text with the wingdings font. Run the application and you will notice the correct font, but when you press the GDI button the Grid loses the font. This GDI button forces the grid to use GDI for draw operations. Interestingly, the font size does appear to work. Please Advise. Thanks, Steve GDIFont_2191.zip

[Administrator]

Hi Steve,

I did some research and tracked it down to the following method in GridGDIPaint.cs:

		IntPtr CreateHFont(GridFontInfo font)
		{
			NativeMethods.LOGFONT logFont = new NativeMethods.LOGFONT();
			logFont.lfFaceName = font.Facename;
			logFont.lfHeight = (int) (font.Size * 128/72f); // TODO: Take also FontUnit and LOGPIXELSX into consideration
			logFont.lfItalic = (byte) (font.Italic ? 1 : 0);
			logFont.lfStrikeOut = (byte) (font.Strikeout ? 1 : 0);
			logFont.lfUnderline = (byte) (font.Underline ? 1 : 0);
			logFont.lfWeight = font.Bold ? 900 : 300;
			return NativeMethods.CreateFontIndirect(ref logFont);
		}

What is missing here is that for the Wingdings font you need to explicitly set logFont.lfCharSet = SYMBOL_CHARSET.

The tricky part is to find out which charset to set based on the facename. I remember there are some GDI font enumeration routines but I first have to find out again how to use them from Windows Forms.

I will let you know once I figured that out. If you also want to give it a try you are also welcome!

Stefan

[Administrator]

Stefan,

I assume this bug occurs for all fonts that don''t use the same character set as MS-Sans Serif. I found this when attempting to change to other fonts, (wingdings is just easier to demonstrate).

I did a little research and you may be able to get the character set by calling GetObject on the font handler. (from http://www.jelovic.com/weblog/e54.htm) I looked at MSDN to verify but I didn''t try it.

Since this is internal code to SF, I assume that the only work-around would be for me to pull out the GDI routines into my code, or get a new dll from SF. Correct?

Let me know if the getObject() works.

Steve

[Administrator]

I replaced the code to use font.ToHfont instead. That seems to work fine (but I haven''t tested various OSes, framework versions etc.)

You should open a direct trac incident. Then we can give you access to a private build with these changes.

Stefan

[Administrator]

Thanks Stefan. I have opened incident 13373.

[Administrator]

Hi Stefan,

Using the example in this thread and a memory profiler, it appears that each time the GDI button is pressed that 2 GDIFontStyleInfo objects are being created, but are not being released. We are using the scitech memory profiler found at http://www.scitech.se/memprofiler/.

Thanks,
Steve

[Administrator]

Additional info -- The GDIFontStyleInfo objects are being held in a hash table.

[Administrator]

Correction - GridFontInfo object is being held by the hash table.

[Administrator]

Hi Steve,

do you have the grid source code?

If yes, try to replace the following method in Grid\Src\Interop\GridGdiPaint.cs

		private void Application_Idle(object sender, EventArgs e)
		{
			brushes.Clear();
			fonts.Clear();
// Added:
			safedHFonts.Clear();
			safedHBrushs.Clear();
		}

Does this fix the problem you see?

Stefan

[Administrator]

Yes. After some difficulties of making a runtime with the source code I was able to make a sample and discovered that GridFontInfo is NOT being held after your suggested changes. Great Work!!

Is this something we can expect in a future release? Would it be possible to open a direct trac to get a private build? Please Advise.

Thanks Again!
Steve

>Hi Steve,
>
>do you have the grid source code?
>
>If yes, try to replace the following method in Grid\Src\Interop\GridGdiPaint.cs
>
>

>		private void Application_Idle(object sender, EventArgs e)
>		{
>			brushes.Clear();
>			fonts.Clear();
>// Added:
>			safedHFonts.Clear();
>			safedHBrushs.Clear();
>		}
>

>
>Does this fix the problem you see?
>
>Stefan
>

[Administrator]

Sure, the next private build will have those changes.

Thanks for your feedback that it is fine now.

Stefan