Core: Enable TaskDialogs to associate view (#17373)

* Core: Add possibility for task dialogs to associate a view and be able to close when associated view is closed.

* TaskImage: Use task dialog view association.

* Sketcher: Use task dialog view association. Preventing crash (https://github.com/FreeCAD/FreeCAD/issues/16702)

* EditableDatumLabel: Use QPointer to prevent crash

src/Gui/Application.cpp

@@ -1411,6 +1411,11 @@ void Application::viewActivated(MDIView* pcView)
     }
 }
 
+/// Gets called if a view gets closed
+void Application::viewClosed(MDIView* pcView)
+{
+    signalCloseView(pcView);
+}
 
 void Application::updateActive()
 {

src/Gui/Application.h

@@ -97,6 +97,8 @@ public:
     void detachView(Gui::BaseView* pcView);
     /// get called if a view gets activated, this manage the whole activation scheme
     void viewActivated(Gui::MDIView* pcView);
+    /// get called if a view gets closed
+    void viewClosed(Gui::MDIView* pcView);
     /// call update to all documents and all views (costly!)
     void onUpdate();
     /// call update to all views of the active document
@@ -137,6 +139,8 @@ public:
     boost::signals2::signal<void (const Gui::Document&)> signalShowHidden;
     /// signal on activating view
     boost::signals2::signal<void (const Gui::MDIView*)> signalActivateView;
+    /// signal on closing view
+    boost::signals2::signal<void (const Gui::MDIView*)> signalCloseView;
     /// signal on entering in edit mode
     boost::signals2::signal<void (const Gui::ViewProviderDocumentObject&)> signalInEdit;
     /// signal on leaving edit mode

src/Gui/EditableDatumLabel.h

@@ -25,6 +25,7 @@
 #define GUI_EDITABLEDATUMLABEL_H
 
 #include <QObject>
+#include <QPointer>
 #include <Gui/QuantitySpinBox.h>
 
 #include "SoDatumLabel.h"
@@ -98,7 +99,7 @@ private:
 private:
     SoSeparator* root;
     SoTransform* transform;
-    View3DInventorViewer* viewer;
+    QPointer<View3DInventorViewer> viewer;
     QuantitySpinBox* spinBox;
     SoNodeSensor* cameraSensor;
     SbVec3f midpos;

src/Gui/MDIView.cpp

@@ -209,6 +209,8 @@ void MDIView::closeEvent(QCloseEvent *e)
 {
     if (canClose()) {
         e->accept();
+        Application::Instance->viewClosed(this);
+
         if (!bIsPassive) {
             // must be detached so that the last view can get asked
             Document* doc = this->getGuiDocument();

src/Gui/TaskView/TaskDialog.cpp

@@ -27,6 +27,13 @@
 # include <QMessageBox>
 #endif
 
+#include <App/Document.h>
+#include <Gui/Application.h>
+#include <Gui/Document.h>
+#include <Gui/View3DInventor.h>
+#include <Gui/ViewProviderDocumentObject.h>
+
+
 #include "TaskDialog.h"
 #include "TaskView.h"
 
@@ -42,6 +49,8 @@ TaskDialog::TaskDialog()
     : QObject(nullptr), pos(North)
     , escapeButton(true)
     , autoCloseTransaction(false)
+    , autoCloseDeletedDocument(false)
+    , autoCloseClosedView(false)
 {
 
 }
@@ -96,6 +105,25 @@ bool TaskDialog::canClose() const
     return (ret == QMessageBox::Yes);
 }
 
+void TaskDialog::associateToObject3dView(App::DocumentObject* obj)
+{
+    if (!obj) {
+        return;
+    }
+
+    Gui::Document* guiDoc = Gui::Application::Instance->getDocument(obj->getDocument());
+    auto* vp = Gui::Application::Instance->getViewProvider(obj);
+    auto* vpdo = static_cast<Gui::ViewProviderDocumentObject*>(vp);
+    auto* view = guiDoc->openEditingView3D(vpdo);
+
+    if (!view) {
+        return;
+    }
+
+    setAssociatedView(view);
+    setAutoCloseOnClosedView(true);
+}
+
 //==== calls from the TaskView ===============================================================
 
 void TaskDialog::open()
@@ -118,6 +146,11 @@ void TaskDialog::autoClosedOnDeletedDocument()
 
 }
 
+void TaskDialog::autoClosedOnClosedView()
+{
+
+}
+
 void TaskDialog::clicked(int)
 {
 

src/Gui/TaskView/TaskDialog.h

@@ -33,10 +33,11 @@
 
 
 namespace App {
-
+class DocumentObject;
 }
 
 namespace Gui {
+class MDIView;
 namespace TaskView {
 
 class TaskContent;
@@ -104,6 +105,22 @@ public:
     { return documentName; }
     void setDocumentName(const std::string& doc)
     { documentName = doc; }
+
+    /// Defines whether a task dialog must be closed if the associated view
+    /// is deleted.
+    void setAutoCloseOnClosedView(bool on) {
+        autoCloseClosedView = on;
+    }
+    bool isAutoCloseOnClosedView() const {
+        return autoCloseClosedView;
+    }
+    void associateToObject3dView(App::DocumentObject* obj);
+
+    const Gui::MDIView* getAssociatedView() const
+    { return associatedView; }
+    void setAssociatedView(const Gui::MDIView* view)
+    { associatedView = view; }
+
     /*!
       Indicates whether this task dialog allows other commands to modify
       the document while it is open.
@@ -136,6 +153,9 @@ public:
     /// is called by the framework when the dialog is automatically closed due to
     /// deleting the document
     virtual void autoClosedOnDeletedDocument();
+    /// is called by the framework when the dialog is automatically closed due to
+    /// closing of associated view
+    virtual void autoClosedOnClosedView();
     /// is called by the framework if a button is clicked which has no accept or reject role
     virtual void clicked(int);
     /// is called by the framework if the dialog is accepted (Ok)
@@ -160,9 +180,11 @@ protected:
 
 private:
     std::string documentName;
+    const Gui::MDIView* associatedView;
     bool escapeButton;
     bool autoCloseTransaction;
     bool autoCloseDeletedDocument;
+    bool autoCloseClosedView;
 
     friend class TaskDialogAttorney;
 };

src/Gui/TaskView/TaskImage.cpp

@@ -679,9 +679,7 @@ TaskImageDialog::TaskImageDialog(Image::ImagePlane* obj)
 {
     addTaskBox(Gui::BitmapFactory().pixmap("image-plane"), widget);
 
-    auto doc = obj->getDocument();
-    setDocumentName(doc->getName());
-    setAutoCloseOnDeletedDocument(true);
+    associateToObject3dView(obj);
 }
 
 void TaskImageDialog::open()

src/Gui/TaskView/TaskView.cpp

@@ -295,6 +295,9 @@ TaskView::TaskView(QWidget *parent)
     connectApplicationDeleteDocument = 
     App::GetApplication().signalDeleteDocument.connect
         (std::bind(&Gui::TaskView::TaskView::slotDeletedDocument, this, sp::_1));
+    connectApplicationClosedView =
+    Gui::Application::Instance->signalCloseView.connect
+        (std::bind(&Gui::TaskView::TaskView::slotViewClosed, this, sp::_1));
     connectApplicationUndoDocument = 
     App::GetApplication().signalUndoDocument.connect
         (std::bind(&Gui::TaskView::TaskView::slotUndoDocument, this, sp::_1));
@@ -310,6 +313,7 @@ TaskView::~TaskView()
 {
     connectApplicationActiveDocument.disconnect();
     connectApplicationDeleteDocument.disconnect();
+    connectApplicationClosedView.disconnect();
     connectApplicationUndoDocument.disconnect();
     connectApplicationRedoDocument.disconnect();
     Gui::Selection().Detach(this);
@@ -479,6 +483,29 @@ void TaskView::slotDeletedDocument(const App::Document& doc)
     }
 }
 
+void TaskView::slotViewClosed(const Gui::MDIView* view)
+{
+    // It can happen that only a view is closed an not the document
+    if (ActiveDialog) {
+        if (ActiveDialog->isAutoCloseOnClosedView()) {
+            const Gui::MDIView* associatedView = ActiveDialog->getAssociatedView();
+            if (!associatedView) {
+                Base::Console().Warning(std::string("TaskView::slotViewClosed"),
+                    "No view associated\n");
+            }
+
+            if (associatedView == view) {
+                ActiveDialog->autoClosedOnClosedView();
+                removeDialog();
+            }
+        }
+    }
+
+    if (!ActiveDialog) {
+        updateWatcher();
+    }
+}
+
 void TaskView::transactionChangeOnDocument(const App::Document& doc)
 {
     if (ActiveDialog) {

src/Gui/TaskView/TaskView.h

@@ -37,6 +37,7 @@ class Property;
 }
 
 namespace Gui {
+class MDIView;
 class ControlSingleton;
 namespace DockWnd{
 class ComboView;
@@ -183,6 +184,7 @@ private:
     void tryRestoreWidth();
     void slotActiveDocument(const App::Document&);
     void slotDeletedDocument(const App::Document&);
+    void slotViewClosed(const Gui::MDIView*);
     void slotUndoDocument(const App::Document&);
     void slotRedoDocument(const App::Document&);
     void transactionChangeOnDocument(const App::Document&);
@@ -210,6 +212,7 @@ protected:
 
     Connection connectApplicationActiveDocument;
     Connection connectApplicationDeleteDocument;
+    Connection connectApplicationClosedView;
     Connection connectApplicationUndoDocument;
     Connection connectApplicationRedoDocument;
 };

src/Mod/Sketcher/Gui/TaskDlgEditSketch.cpp

@@ -79,6 +79,8 @@ TaskDlgEditSketch::TaskDlgEditSketch(ViewProviderSketch* sketchView)
         std::bind(&SketcherGui::TaskDlgEditSketch::slotToolChanged, this, sp::_1));
 
     ToolSettings->setHidden(true);
+
+    associateToObject3dView(sketchView->getObject());
 }
 
 TaskDlgEditSketch::~TaskDlgEditSketch()
@@ -145,4 +147,10 @@ bool TaskDlgEditSketch::reject()
 }
 
 
+void TaskDlgEditSketch::autoClosedOnClosedView()
+{
+    // Make sure the edit mode is exited when the view is closed.
+    reject();
+}
+
 #include "moc_TaskDlgEditSketch.cpp"

src/Mod/Sketcher/Gui/TaskDlgEditSketch.h

@@ -67,6 +67,7 @@ public:
     {
         return false;
     }
+    void autoClosedOnClosedView() override;
 
     /// returns for Close and Help button
     QDialogButtonBox::StandardButtons getStandardButtons() const override