REFERENCE GUIDE

Table 1.8Dialog box keyboardinterfaceKeyDOWNENTERESCAPELEFfRIGHTSHIFf+TABTABUPActionMoves the input focus to the next control that has theWS_GROUP style.Sends a WM_ COMMAND message to the dialogfunction. The wParam parameter is set to 1 or thedefault button.Sends a WM_ COMMAND message to the dialogfunction. The wParam parameter is set to 2.Same as UP.Same as DOWN.Moves the input focus to the previous control that hasthe WS_TABSTOP style.Moves the input focus to the next control that has theWS_TABSTOP style.Moves the input focus to the previous control that hasthe WS_GROUP style.The TAB and DIRECTION keys have no effect if the controls in thedialog box do not have the WS_TABSTOP or WS_GROUP style.The keys have no effect in a modeless dialog box if theIs Dialog Message function is not used to filter messages for thedialog box.t:> For applications that use accelerators and have modeless dialogboxes, the IsDialogMessage function must be called before theTranslateAccelerator function. Otherwise, the keyboard interfacefor the dialog box may not be processed correctly.Applications that have modeless dialog boxes and want thoseboxes to have the special keyboard interface must filter allmessages retrieved from the application queue through theIs Dialog Message function before carrying out any otherprocessing. This means that the application must pass themessage to the function immediately after retrieving the messageby using the GetMessage or PeekMessage function. Mostapplications that have modeless dialog boxes incorporate theIsDialogMessage function as part of the main message loop in theWinMain function. The IsDialogMessage function automaticallyprocesses any messages for the dialog box. This means that if thefunction returns a nonzero value, the message does not requireadditional processing and must not be passed to theTranslateMessage or DispatchMessage function.The IsDialogMessage function also processes the ALT+mnemonicsequence.Chapter 1, Window manager interface functions 67