protected override void RaiseAllCanExecuteChanged() { base.RaiseAllCanExecuteChanged(); ImportAttachmentFromDiskCommand.RaiseCanExecuteChanged(); ImportAttachmentFromClipboardCommand.RaiseCanExecuteChanged(); SaveAttachmentToDiskCommand.RaiseCanExecuteChanged(); OpenAttachmentCommand.RaiseCanExecuteChanged(); DeleteAttachmentCommand.RaiseCanExecuteChanged(); }