Adding support for new 'desktop' preferences

cmd/winfe/prefs/nsprefui/src/framedlg.cpp

@@ -215,6 +215,8 @@ DialogProc(HWND hwndDlg, UINT uMsg, WPARAM wParam, LPARAM lParam)
 /////////////////////////////////////////////////////////////////////////////
 // CPropertyFrameDialog implementation
 
+HWND CPropertyFrameDialog::m_hwndShowing = 0;
+
 // Constructor
 CPropertyFrameDialog::CPropertyFrameDialog(HWND		   hwndOwner,
 										   int		   x,
@@ -286,7 +288,7 @@ CPropertyFrameDialog::InitDialog(HWND hdlg)
 	HWND	hwnd;
 
 	// Save away the window handle for the dialog
-	m_hdlg = hdlg;
+	m_hwndShowing = m_hdlg = hdlg;
 
 	// Get the bold font we will be using. It's the same font as the
 	// dialog box uses, except it's bold
@@ -885,6 +887,7 @@ CPropertyFrameDialog::DoModal()
 	// Cleanup
 	if (m_pCurPage)
 		m_pCurPage->m_pPage->SetObjects(0, NULL);
+    m_hwndShowing = 0;
 	DestroyWindow(m_hdlg);
 
 	return nResult;

cmd/winfe/prefs/nsprefui/src/framedlg.h

@@ -48,12 +48,18 @@ class CPropertyFrameDialog {
 		// a chance to translate accelerators
 		HRESULT		TranslateAccelerator(LPMSG);
 
+        // Static functions to be used to ensure only one property frame is
+        // showing.
+        static BOOL IsShowing() { return m_hwndShowing != 0; }
+        static void BringToTop() { ::BringWindowToTop(m_hwndShowing); }
+
 	protected:
 		int			RunModalLoop();
 
 	private:
 		HWND				 m_hdlg;
 		HWND				 m_hwndOwner;
+        static HWND          m_hwndShowing;
 		int					 m_x, m_y;
 		LPCSTR				 m_lpszCaption;
 		ULONG				 m_nInitialCategory;

cmd/winfe/prefs/nsprefui/src/prefui.cpp

@@ -330,20 +330,27 @@ NS_CreatePropertyFrame(HWND     			   		 hwndOwner,
 	if (nCategories == 0)
 		return ResultFromScode(S_FALSE);
 
-	// Create the property frame dialog
-	CPropertyFrameDialog	dialog(hwndOwner, x, y, lpszCaption, lpfnNetHelp);
-
-	// Initialize the property frame dialog
-	hres = dialog.CreatePages(nCategories, lplpProviders, nInitial);
-	if (FAILED(hres)) {
-#ifdef _DEBUG
-		OutputDebugString("CPropertyFrameDialog::CreatePages failed\n");
-#endif
-		return hres;
-	}
-
-	// Display the property frame as a modal dialog
-	dialog.DoModal();
+    // Catch cases where prefs already showing; we can get here if prefs are
+    // showing and user does "mozilla -prefs", for example.
+    if ( CPropertyFrameDialog::IsShowing() ) {
+        // Bring existing property frame dialog to top.
+        CPropertyFrameDialog::BringToTop();
+    } else {
+    	// Create the property frame dialog
+    	CPropertyFrameDialog	dialog(hwndOwner, x, y, lpszCaption, lpfnNetHelp);
+    
+    	// Initialize the property frame dialog
+    	hres = dialog.CreatePages(nCategories, lplpProviders, nInitial);
+    	if (FAILED(hres)) {
+    #ifdef _DEBUG
+    		OutputDebugString("CPropertyFrameDialog::CreatePages failed\n");
+    #endif
+    		return hres;
+    	}
+    
+    	// Display the property frame as a modal dialog
+    	dialog.DoModal();
+    }
 	return NOERROR;
 }