.NET: Setting the Default Font in a Windows Mobile/Compact Framework Custom Control

This tip applies to creating a custom control using Visual Studio 2008, Compact Framework 3.5, and Windows Mobile 5 or 6.

To set a default font in a Windows Mobile/Compact Framework custom control:

1. In the constructor for the custom class, set the default font:

   [c#]
   public partial class ExampleControl : Control
   {
       private static readonly Font fontReset =
           new Font("Tahoma", 8F, FontStyle.Regular);
   
       public ListInput()
       {
           this.Font = fontReset;
       }
   }
   

2. In the xmta Design Time Attribute File, set the default font:

       <Class Name="Company.NameSpace.ExampleControl">
           <ApplyDeviceDefaults>
               <PropertyName>Font</PropertyName>
               <ApplyDefaults>false</ApplyDefaults>
           </ApplyDeviceDefaults>
           <Property Name="Font">
               <DefaultValue>
                   <Value>Tahoma, 8pt</Value>
                   <Type>System.Drawing.Font,
                   System.Drawing,
                   Version=2.0.0.0,
                   Culture=neutral,
                   PublicKeyToken=b03f5f7f11d50a3a</Type>
               </DefaultValue>
           </Property>
       </Class>
   

An explanation: The ApplyDeviceDefaults tag is necessary to keep the designer from resetting the font to the Control class default of 9 point. The DefaultValue tag sets the default in the designer. This makes it so that if you right click on the property and select Reset, it will return to this font.

The especially tricky part, though, is that although your control will use the Compact Framework 3.5, and that is the version of the font class that is used in the emulator, in the designer you are using the full version of the .NET Framework 2.0. If you try to reference the 3.5 version of the Font class in the xmta file, it won't be recognised in the designer as the class the font is instantiated from, and Reset will return the font to the Control class's default, instead of your default. It seems so simple, but it is so underdocumented it took me hours of fooling with it before I understood what was going on.

Supplemental information that may help can be found in the article Creating and Migrating Smart Device Custom Controls by Using Visual Studio 2005.