Dialogs:

- implement a mechanisme to query the widgetset how and when to handle DoShow, DoCanClose and DoClose.
- implement QueryWSEventCapabilities for Win32 widgetset

git-svn-id: trunk@52850 -

lcl/dialogs.pp

@@ -58,6 +58,10 @@ type
 
   { TCommonDialog }
 
+  TCDWSEventCapability = (cdecWSPerformsDoShow, cdecWSPerformsDoCanClose, cdecWSPerformsDoClose,
+                          cdecWSNOCanCloseSupport);
+  TCDWSEventCapabilities = set of TCDWSEventCapability;
+
   TCommonDialog = class(TLCLComponent)
   private
     FHandle : THandle;
@@ -72,6 +76,7 @@ type
     FDoShowCalled: Boolean;
     FDoCloseCalled: Boolean;
     FClosing: boolean;
+    FWSEventCapabilities :TCDWSEventCapabilities;
     procedure SetHandle(const AValue: THandle);
     function IsTitleStored: boolean;
   protected

lcl/include/commondialog.inc

@@ -36,6 +36,7 @@ begin
     try
       FUserChoice := mrNone;
       ResetShowCloseFlags;
+      FWSEventCapabilities := TWSCommonDialogClass(WidgetSetClass).QueryWSEventCapabilities(Self);
       Handle := TWSCommonDialogClass(WidgetSetClass).CreateHandle(Self);
       Result:= DoExecute;
       Close;
@@ -55,7 +56,7 @@ procedure TCommonDialog.Close;
 begin
   if HandleAllocated and not FClosing then begin
     FClosing := true;
-    if not FDoCloseCalled then
+    if (not FDoCloseCalled) and (not (cdecWSPerformsDoClose in FWSEventCapabilities)) then
       DoClose;
     TWSCommonDialogClass(WidgetSetClass).DestroyHandle(Self);
     FHandle := 0;
@@ -73,7 +74,7 @@ end;
 procedure TCommonDialog.DoCanClose(var CanClose: Boolean);
 begin
   FDoCanCloseCalled := True;
-  if Assigned(FOnCanClose) then
+  if Assigned(FOnCanClose) and (not (cdecWSNOCanCloseSupport in FWSEventCapabilities)) then
     OnCanClose(Self, CanClose);
 end;
 
@@ -128,10 +129,17 @@ function TCommonDialog.DoExecute : boolean;
 var
   CanClose: boolean;
 begin
+  {
+    Various widgetsets may or may not call DoShow, DoCanClose or DoClose from within
+    the WS implementation.
+    If the WS calls any of these, we assume that we should NOT call them from here.
+    Checking for FDoShowCalled (etc) alone is not enough, since it may very well be that
+    the WS wants to (deiberately) call the methos at a later point in time.
+  }
   {$ifdef DebugCommonDialogEvents}
   debugln(['TCommonDialog.DoExecute A']);
   {$endif}
-  if not FDoShowCalled then
+  if (not FDoShowCalled) and (not (cdecWSPerformsDoShow in FWSEventCapabilities)) then
   begin
     {$ifdef DebugCommonDialogEvents}
     debugln(['TCommonDialog.DoExecute calling DoShow']);
@@ -146,7 +154,7 @@ begin
   debugln(['TCommonDialog.DoExecute after WS_ShowModal, FCanCloseCalled=',FDoCanCloseCalled,' FUserChoice=',ModalResultStr[FUserChoice]]);
   {$endif}
   // can close was called from widgetset loop
-  if not FDoCanCloseCalled then
+  if (not FDoCanCloseCalled) and ((FWSEventCapabilities * [cdecWSPerformsDoCanClose,cdecWSNOCanCloseSupport]) = []) then
   begin
     repeat
       {$ifdef DebugCommonDialogEvents}

lcl/interfaces/win32/win32wsdialogs.pp

@@ -82,6 +82,7 @@ type
     class function CreateHandle(const ACommonDialog: TCommonDialog): THandle; override;
     class procedure DestroyHandle(const ACommonDialog: TCommonDialog); override;
     class procedure ShowModal(const ACommonDialog: TCommonDialog); override;
+    class function QueryWSEventCapabilities(const ACommonDialog: TCommonDialog): TCDWSEventCapabilities; override;
   end;
 
   { TWin32WSSaveDialog }
@@ -91,6 +92,7 @@ type
     class function CreateHandle(const ACommonDialog: TCommonDialog): THandle; override;
     class procedure DestroyHandle(const ACommonDialog: TCommonDialog); override;
     class procedure ShowModal(const ACommonDialog: TCommonDialog); override;
+    class function QueryWSEventCapabilities(const ACommonDialog: TCommonDialog): TCDWSEventCapabilities; override;
   end;
 
   { TWin32WSSelectDirectoryDialog }
@@ -100,6 +102,7 @@ type
     class function CreateOldHandle(const ACommonDialog: TCommonDialog): THandle;
   published
     class function CreateHandle(const ACommonDialog: TCommonDialog): THandle; override;
+    class function QueryWSEventCapabilities(const ACommonDialog: TCommonDialog): TCDWSEventCapabilities; override;
   end;
 
   { TWin32WSColorDialog }
@@ -109,6 +112,7 @@ type
     class function CreateHandle(const ACommonDialog: TCommonDialog): THandle; override;
     class procedure ShowModal(const ACommonDialog: TCommonDialog); override;
     class procedure DestroyHandle(const ACommonDialog: TCommonDialog); override;
+    class function QueryWSEventCapabilities(const ACommonDialog: TCommonDialog): TCDWSEventCapabilities; override;
   end;
 
   { TWin32WSColorButton }
@@ -122,6 +126,7 @@ type
   TWin32WSFontDialog = class(TWSFontDialog)
   published
     class function CreateHandle(const ACommonDialog: TCommonDialog): THandle; override;
+    class function QueryWSEventCapabilities(const ACommonDialog: TCommonDialog): TCDWSEventCapabilities; override;
   end;
 
 
@@ -411,6 +416,12 @@ begin
   end;
 end;
 
+class function TWin32WSColorDialog.QueryWSEventCapabilities(
+  const ACommonDialog: TCommonDialog): TCDWSEventCapabilities;
+begin
+  Result := [cdecWSNoCanCloseSupport];
+end;
+
 procedure UpdateStorage(Wnd: HWND; OpenFile: LPOPENFILENAME);
 var
   FilesSize: SizeInt;
@@ -997,6 +1008,12 @@ begin
   end;
 end;
 
+class function TWin32WSOpenDialog.QueryWSEventCapabilities(
+  const ACommonDialog: TCommonDialog): TCDWSEventCapabilities;
+begin
+  Result := [cdecWSPerformsDoShow,cdecWSPerformsDoCanClose];
+end;
+
 { TWin32WSSaveDialog }
 
 class function TWin32WSSaveDialog.CreateHandle(const ACommonDialog: TCommonDialog): THandle;
@@ -1065,6 +1082,12 @@ begin
   end;
 end;
 
+class function TWin32WSSaveDialog.QueryWSEventCapabilities(
+  const ACommonDialog: TCommonDialog): TCDWSEventCapabilities;
+begin
+  Result := [cdecWSPerformsDoShow,cdecWSPerformsDoCanClose];
+end;
+
 { TWin32WSFontDialog }
 
 class function TWin32WSFontDialog.CreateHandle(const ACommonDialog: TCommonDialog): THandle;
@@ -1150,6 +1173,12 @@ begin
   Result := 0;
 end;
 
+class function TWin32WSFontDialog.QueryWSEventCapabilities(
+  const ACommonDialog: TCommonDialog): TCDWSEventCapabilities;
+begin
+  Result := [cdecWSPerformsDoShow, cdecWSPerformsDoClose, cdecWSNoCanCloseSupport];
+end;
+
 { TWin32WSCommonDialog }
 
 class function TWin32WSCommonDialog.CreateHandle(const ACommonDialog: TCommonDialog): THandle;
@@ -1208,6 +1237,15 @@ begin
     Result := CreateOldHandle(ACommonDialog);
 end;
 
+class function TWin32WSSelectDirectoryDialog.QueryWSEventCapabilities(
+  const ACommonDialog: TCommonDialog): TCDWSEventCapabilities;
+begin
+  if CanUseVistaDialogs(TSelectDirectoryDialog(ACommonDialog)) then
+    Result := [cdecWSPerformsDoShow,cdecWSPerformsDoCanClose]
+  else
+    Result := [cdecWSPerformsDoShow, cdecWSPerformsDoClose, cdecWSNoCanCloseSupport];
+end;
+
 class function TWin32WSSelectDirectoryDialog.CreateOldHandle(
   const ACommonDialog: TCommonDialog): THandle;
 var

lcl/widgetset/wsdialogs.pp

@@ -51,6 +51,7 @@ type
     class function  CreateHandle(const ACommonDialog: TCommonDialog): THandle; virtual;
     class procedure ShowModal(const ACommonDialog: TCommonDialog); virtual;
     class procedure DestroyHandle(const ACommonDialog: TCommonDialog); virtual;
+    class function QueryWSEventCapabilities(const ACommonDialog: TCommonDialog): TCDWSEventCapabilities; virtual;
   end;
 
   { TWSFileDialog }
@@ -120,6 +121,12 @@ class procedure TWSCommonDialog.DestroyHandle(const ACommonDialog: TCommonDialog
 begin
 end;
 
+class function TWSCommonDialog.QueryWSEventCapabilities(
+  const ACommonDialog: TCommonDialog): TCDWSEventCapabilities;
+begin
+  Result := [];
+end;
+
 class procedure TWSCommonDialog.ShowModal(const ACommonDialog: TCommonDialog);
 begin
 end;