allocate size for the extra controls in the file dialog (#9679)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@58270 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/filedlg.h

@@ -120,8 +120,6 @@ public:
     // create the window containing the extra controls we want to show in it
     typedef wxWindow *(*ExtraControlCreatorFunction)(wxWindow*);
 
-    // extra controls are currently supported in GTK and generic versions
-    // only currently
     virtual bool SupportsExtraControl() const { return false; }
 
     bool SetExtraControlCreator(ExtraControlCreatorFunction WXUNUSED(c));
@@ -155,6 +153,11 @@ protected:
 
     // returns true if control is created (if it already exists returns false)
     bool CreateExtraControl();
+    // return true if SetExtraControlCreator() was called
+    bool HasExtraControlCreator() const
+        { return m_extraControlCreator != NULL; }
+    // get the size of the extra control by creating and deleting it
+    wxSize GetExtraControlSize();
 
 private:
     ExtraControlCreatorFunction m_extraControlCreator;

include/wx/msw/filedlg.h

@@ -32,6 +32,10 @@ public:
     virtual void SetPath(const wxString& path);
     virtual void GetPaths(wxArrayString& paths) const;
     virtual void GetFilenames(wxArrayString& files) const;
+#ifndef __WXWINCE__
+    virtual bool SupportsExtraControl() const { return true; }
+#endif // __WXWINCE__
+    void MSWOnInitDialogHook(WXHWND hwnd);
 
     virtual int ShowModal();
 

include/wx/msw/private.h

@@ -605,14 +605,25 @@ private:
 class GlobalPtr
 {
 public:
+    // default ctor, call Init() later
+    GlobalPtr()
+    {
+        m_hGlobal = NULL;
+    }
+
     // allocates a block of given size
-    GlobalPtr(size_t size, unsigned flags = GMEM_MOVEABLE)
+    void Init(size_t size, unsigned flags = GMEM_MOVEABLE)
     {
         m_hGlobal = ::GlobalAlloc(flags, size);
         if ( !m_hGlobal )
             wxLogLastError(_T("GlobalAlloc"));
     }
 
+    GlobalPtr(size_t size, unsigned flags = GMEM_MOVEABLE)
+    {
+        Init(size, flags);
+    }
+
     ~GlobalPtr()
     {
         if ( m_hGlobal && ::GlobalFree(m_hGlobal) )

src/common/fldlgcmn.cpp

@@ -168,6 +168,18 @@ bool wxFileDialogBase::CreateExtraControl()
     return true;
 }
 
+wxSize wxFileDialogBase::GetExtraControlSize()
+{
+    if ( !m_extraControlCreator )
+        return wxDefaultSize;
+
+    // create the extra control in an empty dialog just to find its size: this
+    // is not terribly efficient but we do need to know the size before
+    // creating the native dialog and this seems to be the only way
+    wxDialog dlg(NULL, wxID_ANY, "");
+    return (*m_extraControlCreator)(&dlg)->GetSize();
+}
+
 //----------------------------------------------------------------------------
 // wxFileDialog convenience functions
 //----------------------------------------------------------------------------

src/msw/filedlg.cpp

@@ -86,6 +86,14 @@ wxFileDialogHookFunction(HWND      hDlg,
 {
     switch ( iMsg )
     {
+        case WM_INITDIALOG:
+            {
+                OPENFILENAME* ofn = reinterpret_cast<OPENFILENAME *>(lParam);
+                reinterpret_cast<wxFileDialog *>(ofn->lCustData)
+                    ->MSWOnInitDialogHook((WXHWND)hDlg);
+            }
+            break;
+
         case WM_NOTIFY:
             {
                 OFNOTIFY *pNotifyCode = reinterpret_cast<OFNOTIFY *>(lParam);
@@ -360,6 +368,15 @@ static bool ShowCommFileDialog(OPENFILENAME *of, long style)
     return true;
 }
 
+void wxFileDialog::MSWOnInitDialogHook(WXHWND hwnd)
+{
+   SetHWND(hwnd);
+
+   CreateExtraControl();
+
+   SetHWND(NULL);
+}
+
 int wxFileDialog::ShowModal()
 {
     HWND hWnd = 0;
@@ -385,7 +402,7 @@ int wxFileDialog::ShowModal()
         in the upper left of the frame, it does not center
         automatically.
     */
-    if (m_bMovedWindow) // we need these flags.
+    if (m_bMovedWindow || HasExtraControlCreator()) // we need these flags.
     {
         msw_flags |= OFN_EXPLORER|OFN_ENABLEHOOK;
 #ifndef __WXWINCE__
@@ -421,6 +438,37 @@ int wxFileDialog::ShowModal()
     of.lpstrFileTitle    = titleBuffer;
     of.nMaxFileTitle     = wxMAXFILE + 1 + wxMAXEXT;
 
+#ifndef __WXWINCE__
+    GlobalPtr hgbl;
+    if ( HasExtraControlCreator() )
+    {
+        msw_flags |= OFN_ENABLETEMPLATEHANDLE;
+
+        hgbl.Init(256, GMEM_ZEROINIT);
+        GlobalPtrLock hgblLock(hgbl);
+        LPDLGTEMPLATE lpdt = static_cast<LPDLGTEMPLATE>(hgblLock.Get());
+
+        // Define a dialog box.
+
+        lpdt->style = DS_CONTROL | WS_CHILD | WS_CLIPSIBLINGS;
+        lpdt->cdit = 0;         // Number of controls
+        lpdt->x = 0;
+        lpdt->y = 0;
+
+        wxSize extra_size = GetExtraControlSize();
+        // setting cx doesn't change the width of the dialog
+        lpdt->cx = extra_size.GetWidth();
+        // Dividing by 2 gives expected height on WinXP and Wine.
+        // I don't know why (MW).
+        lpdt->cy = extra_size.GetHeight() / 2;
+
+        // after the DLGTEMPLATE there are 3 additional WORDs for dialog menu,
+        // class and title, all three set to zeros.
+
+        of.hInstance = (HINSTANCE)lpdt;
+    }
+#endif // __WXWINCE__
+
     // Convert forward slashes to backslashes (file selector doesn't like
     // forward slashes) and also squeeze multiple consecutive slashes into one
     // as it doesn't like two backslashes in a row neither