void ChainToKeymap (wxKeymap *next, Bool prefix)
Multiple keymaps can be chained off one keymap using ChainToKeymap. If next will be used to handle events which are not handled by this keymap. If prefix is TRUE, then next will take precedence over other keymaps already chained to this one. Keymaps can be chained together arbitrarily, but cannot be chained in a cycle. The AdjustUsage method of next will be called when it is added to the keymap chain list.