Add non modal dialog to project

If we have an existing project one needs to do the following steps to add an non-modal dialog.

Example Project:

  ModelessDialog.zip (45,5 KiB)

1. Add a new dialog to the project and add a class for that dialog
2. Add a member variable for the dialog to the application class.
   If our project is called ‘SecondDialog’ the application class would then look like this

   class CSecondDialogApp : public CWinApp
   {
   public:
   	CSecondDialogApp();
    
   	DlgSecond* m_pDlgSecond;
    
   // Überschreibungen
   	public:
   	virtual BOOL InitInstance();
    
   // Implementierung
    
   	DECLARE_MESSAGE_MAP()
   };
    
   extern CSecondDialogApp theApp;

   with m_pDlgSecond the member variable of the new dialog.

   Also add the header file with #include "DlgSecond.h" to the same file.

3. Add an Button (or Menu entry) to the project which shall show the dialog
   This function should then have the following content to open the dialog when the button is clicked

   void CSecondDialogDlg::OnBnClickedButtonShowSecondDialog()
   {
    
   	if (theApp.m_pDlgSecond != NULL) {
   		theApp.m_pDlgSecond->SetForegroundWindow();
   		theApp.m_pDlgSecond->SetFocus();
   	}
   	else {		
   		theApp.m_pDlgSecond = new DlgSecond;
   		theApp.m_pDlgSecond->Create(DlgSecond::IDD);				
   		// Ausgabe initialisieren		
   		theApp.m_pDlgSecond->ShowWindow(SW_SHOW);	
   	}
    
   }

4. Make sure the variable is deleted
   

   CSecondDialogDlg::~CSecondDialogDlg()
   {
   	if (theApp.m_pDlgSecond != NULL) 
   	{
   		delete [] theApp.m_pDlgSecond;
   	}
   }