i am fix call FontLoaderCallback add commit

[CSerX]

Never called FontLoaderCallback, i am fix it. I use this function to load self fonts.

Source/SvgFontManager.cs
@@ -50,10 +50,10 @@
         {
             if (name == null) return null;
             FontFamily ff = null;
-            if (SystemFonts.TryGetValue(name.ToLower(), out ff)) return ff;
+            if (SystemFonts.TryGetValue(name.ToLower(), out ff) && ff != null) return ff;
             if (FontLoaderCallback == null) return null;
             var ff2 = FontLoaderCallback(name);
-            SystemFonts.Add(name.ToLower(), ff2);
+            if (ff2 != null) SystemFonts.Add(name.ToLower(), ff2);
             return ff2;
         }
     }

[mrbean-bremen]

Thanks - the diff had been garbled by the formatting, so I didn't understand this first...
Though I don't understand the change yet.

  if (SystemFonts.TryGetValue(name.ToLower(), out ff)) return ff;

This returns only, if a font was found - so the second check for ff is not needed, as far as I can see.
The second check to avoid adding a null font makes sense to me, but I still don't understand why FontLoaderCallback was not called in the first place.

[CSerX]

I don't know why, result is true and ff is null.
And if FontLoaderCallback return null then it can't be added to SystemFonts.

[mrbean-bremen]

Sorry for the delay!
Strange... I would really like to understand what is going on here before adding this - maybe there is a bug elsewhere. Can you check the value of SystemFonts before that call? Can it be that somehow there is a null as value in the dictionary?

[CSerX]

Sorry, i am undestend. First check not needed, second is required. Beсause FontLoaderCallback can return null, after this dictionary contains null :) (i am debug after first execution)

[mrbean-bremen]

Ok, thanks - that makes sense then! I'll add the second check in this case.