Gui: Fix undo/redo behaviour in transformation tool

If the user clicks on undo while the transformation dialog is
open the currently active transaction will be closed.
From now on any change of the placement won't be recorded any
more so that e.g. canceling the dialog or an undo after
accepting the dialog leads to unexpected behaviour.

To fix the issue two new virtual methods onUndo() and onRedo()
are added to TaskDialog and reimplemented in TaskTransformDialog.
These functions make sure to open a new transaction.

This fixes issue 19152

src/Gui/TaskTransform.cpp

@@ -728,16 +728,31 @@ void TaskTransformDialog::open()
 
     Gui::TaskView::TaskDialog::open();
 
-    Gui::Application::Instance->activeDocument()->openCommand(
-        QT_TRANSLATE_NOOP("Command", "Transform"));
+    openCommand();
+}
+
+void TaskTransformDialog::openCommand()
+{
+    if (auto document = vp->getDocument()) {
+        if (!document->hasPendingCommand()) {
+            document->openCommand(QT_TRANSLATE_NOOP("Command", "Transform"));
+        }
+    }
+}
+
+void TaskTransformDialog::onUndo()
+{
+    openCommand();
+}
+
+void TaskTransformDialog::onRedo()
+{
+    openCommand();
 }
 
 bool TaskTransformDialog::accept()
 {
-    if (auto documentObject = vp->getObject()) {
-        Gui::Document* document =
-            Gui::Application::Instance->getDocument(documentObject->getDocument());
-        assert(document);
+    if (auto document = vp->getDocument()) {
         document->commitCommand();
         document->resetEdit();
         document->getDocument()->recompute();
@@ -748,10 +763,7 @@ bool TaskTransformDialog::accept()
 
 bool TaskTransformDialog::reject()
 {
-    if (auto documentObject = vp->getObject()) {
-        Gui::Document* document =
-            Gui::Application::Instance->getDocument(documentObject->getDocument());
-        assert(document);
+    if (auto document = vp->getDocument()) {
         document->abortCommand();
         document->resetEdit();
         document->getDocument()->recompute();

src/Gui/TaskTransform.h

@@ -166,6 +166,11 @@ public:
     void open() override;
     bool accept() override;
     bool reject() override;
+    void onUndo() override;
+    void onRedo() override;
+
+private:
+    void openCommand();
 
 private:
     ViewProviderDragger* vp;

src/Gui/TaskView/TaskDialog.cpp

@@ -172,6 +172,16 @@ void TaskDialog::helpRequested()
 
 }
 
+void TaskDialog::onUndo()
+{
+
+}
+
+void TaskDialog::onRedo()
+{
+
+}
+
 
 
 

src/Gui/TaskView/TaskDialog.h

@@ -162,8 +162,12 @@ public:
     virtual bool accept();
     /// is called by the framework if the dialog is rejected (Cancel)
     virtual bool reject();
-    /// is called by the framework if the user press the help button 
+    /// is called by the framework if the user press the help button
     virtual void helpRequested();
+    /// is called by the framework if the user press the undo button
+    virtual void onUndo();
+    /// is called by the framework if the user press the redo button
+    virtual void onRedo();
 
     void emitDestructionSignal() {
         Q_EMIT aboutToBeDestroyed();

src/Gui/TaskView/TaskView.cpp

@@ -503,11 +503,15 @@ void TaskView::slotViewClosed(const Gui::MDIView* view)
     }
 }
 
-void TaskView::transactionChangeOnDocument(const App::Document& doc)
+void TaskView::transactionChangeOnDocument(const App::Document& doc, bool undo)
 {
     if (ActiveDialog) {
+        std::string name = ActiveDialog->getDocumentName();
+        if (name == doc.getName()) {
+            undo ? ActiveDialog->onUndo() : ActiveDialog->onRedo();
+        }
+
         if (ActiveDialog->isAutoCloseOnTransactionChange()) {
-            std::string name = ActiveDialog->getDocumentName();
             if (name.empty()) {
                 Base::Console().warning(std::string("TaskView::transactionChangeOnDocument"),
                                         "No document name set\n");
@@ -527,12 +531,12 @@ void TaskView::transactionChangeOnDocument(const App::Document& doc)
 
 void TaskView::slotUndoDocument(const App::Document& doc)
 {
-    transactionChangeOnDocument(doc);
+    transactionChangeOnDocument(doc, true);
 }
 
 void TaskView::slotRedoDocument(const App::Document& doc)
 {
-    transactionChangeOnDocument(doc);
+    transactionChangeOnDocument(doc, false);
 }
 
 /// @cond DOXERR

src/Gui/TaskView/TaskView.h

@@ -187,7 +187,7 @@ private:
     void slotViewClosed(const Gui::MDIView*);
     void slotUndoDocument(const App::Document&);
     void slotRedoDocument(const App::Document&);
-    void transactionChangeOnDocument(const App::Document&);
+    void transactionChangeOnDocument(const App::Document&, bool undo);
 
 protected:
     void keyPressEvent(QKeyEvent* event) override;