Using to non-native filedialog on MacOS for DirectoryPathWidget (#4720)

Moved the filebrowsing from the widget to the delegate (MacOS only)
Fixes #4719

src/Gui/StyledItemDelegates.cpp

@@ -339,16 +339,16 @@ DirectoryPathWidget::DirectoryPathWidget
 {
     lineEdit = new QLineEdit();
 
-    openButton = new QPushButton(tr("Browse"));
+    browseButton = new QPushButton(tr("Browse"));
 
     QHBoxLayout *layout = new QHBoxLayout(this);
     layout->setContentsMargins(0, 0, 0, 0);
     layout->setSpacing(0);
     layout->addWidget(lineEdit, 1);
-    layout->addWidget(openButton, 0);
+    layout->addWidget(browseButton, 0);
 
-    connect(openButton, SIGNAL(clicked()), this, SLOT(openDialog()));
-    connect(lineEdit, SIGNAL(editingFinished()), this, SLOT(lineEditFinished()));
+    connect(browseButton, &QPushButton::clicked, this, &DirectoryPathWidget::handleBrowseClicked);
+    connect(lineEdit, &QLineEdit::editingFinished, this, &DirectoryPathWidget::lineEditFinished);
 }
 
 
@@ -377,28 +377,63 @@ DirectoryPathWidget::setPlaceholderText
 
 
 void
-DirectoryPathWidget::openDialog
+DirectoryPathWidget::setDelegateMode
+(bool delegateMode)
+{
+    this->delegateMode = delegateMode;
+}
+
+
+void
+DirectoryPathWidget::handleBrowseClicked
 ()
 {
-    QFileDialog fileDialog(this);
-    QStringList selectedDirs;
-    fileDialog.setFileMode(QFileDialog::Directory);
-    fileDialog.setOptions(QFileDialog::ShowDirsOnly | QFileDialog::DontResolveSymlinks);
+    if (delegateMode) {
+        QTimer::singleShot(0, this, [=]() {
+            openFileDialog();
+        });
+    } else {
+        openFileDialog();
+    }
+}
+
+
+void
+DirectoryPathWidget::openFileDialog
+()
+{
+#ifdef Q_OS_MACOS
+    // On macOS in delegate mode, emit a signal and let the delegate handle the dialog.
+    // This avoids widget lifecycle issues where the editor is destroyed during
+    // QFileDialog::exec().
+    if (delegateMode) {
+        emit browseRequested();
+        return; // The delegate must take over.
+    }
+#endif
+
+    // Standard modal dialog approach for non-delegate mode or non-macOS
+    QFileDialog dialog(window());
+    dialog.setFileMode(QFileDialog::Directory);
+    dialog.setOptions(  QFileDialog::ShowDirsOnly
+                      | QFileDialog::DontResolveSymlinks);
     QString path = lineEdit->text();
     if (path.isEmpty()) {
         path = QStandardPaths::writableLocation(QStandardPaths::HomeLocation);
     }
-    fileDialog.setDirectory(path);
-    if (fileDialog.exec()) {
-        selectedDirs = fileDialog.selectedFiles();
-    }
-    if (selectedDirs.count() > 0) {
-        QString dir = selectedDirs.at(0);
-        if (dir != "") {
-            lineEdit->setText(dir);
+    dialog.setDirectory(path);
+    bool accepted = false;
+    if (dialog.exec() == QDialog::Accepted) {
+        const QStringList selectedDirs = dialog.selectedFiles();
+        if (! selectedDirs.isEmpty()) {
+            QString selectedDir = selectedDirs.first();
+            if (! selectedDir.isEmpty()) {
+                setPath(selectedDir);
+                accepted = true;
+            }
         }
     }
-    emit editingFinished();
+    emit editingFinished(accepted);
 }
 
 
@@ -412,8 +447,8 @@ DirectoryPathWidget::lineEditFinished
     }
     lineEditAlreadyFinished = true;
 
-    if (! openButton->hasFocus()) {
-        emit editingFinished();
+    if (! browseButton->hasFocus()) {
+        emit editingFinished(true);
     }
 }
 
@@ -435,8 +470,17 @@ DirectoryPathDelegate::createEditor
     Q_UNUSED(index)
 
     DirectoryPathWidget *editor = new DirectoryPathWidget(parent);
+    editor->setDelegateMode(true);
     editor->setPlaceholderText(placeholderText);
-    connect(editor, SIGNAL(editingFinished()), this, SLOT(commitAndCloseEditor()));
+
+    DirectoryPathDelegate *delegate = const_cast<DirectoryPathDelegate*>(this);
+#ifdef Q_OS_MACOS
+    // On macOS, the delegate handles the dialog to prevent lifecycle crashes.
+    connect(editor, &DirectoryPathWidget::browseRequested, delegate, [delegate, editor, index]() {
+        delegate->openFileDialogForEditor(editor, index);
+    });
+#endif
+    connect(editor, &DirectoryPathWidget::editingFinished, delegate, &DirectoryPathDelegate::onEditingFinished);
 
     return editor;
 }
@@ -446,8 +490,9 @@ void
 DirectoryPathDelegate::setEditorData
 (QWidget *editor, const QModelIndex &index) const
 {
-    DirectoryPathWidget *filepath = static_cast<DirectoryPathWidget*>(editor);
-    filepath->setPath(index.data(Qt::DisplayRole).toString());
+    if (DirectoryPathWidget *pathEditor = qobject_cast<DirectoryPathWidget*>(editor)) {
+        pathEditor->setPath(index.data(Qt::EditRole).toString());
+    }
 }
 
 
@@ -455,8 +500,9 @@ void
 DirectoryPathDelegate::setModelData
 (QWidget *editor, QAbstractItemModel *model, const QModelIndex &index) const
 {
-    DirectoryPathWidget *filepath = static_cast<DirectoryPathWidget*>(editor);
-    model->setData(index, filepath->getPath(), Qt::DisplayRole);
+    if (DirectoryPathWidget *pathEditor = qobject_cast<DirectoryPathWidget*>(editor)) {
+        model->setData(index, pathEditor->getPath(), Qt::EditRole);
+    }
 }
 
 
@@ -518,15 +564,62 @@ DirectoryPathDelegate::setPlaceholderText
 
 
 void
-DirectoryPathDelegate::commitAndCloseEditor
-()
+DirectoryPathDelegate::onEditingFinished
+(bool accepted)
 {
-    QWidget *editor = qobject_cast<QWidget*>(sender());
-    emit commitData(editor);
-    emit closeEditor(editor);
+    DirectoryPathWidget *editor = qobject_cast<DirectoryPathWidget*>(sender());
+    if (editor) {
+        if (accepted) {
+            emit commitData(editor);
+        }
+        emit closeEditor(editor);
+    }
 }
 
 
+#ifdef Q_OS_MACOS
+void
+DirectoryPathDelegate::closeEditorForWidget
+(QWidget *editor)
+{
+    if (editor) {
+        emit closeEditor(editor, QAbstractItemDelegate::NoHint);
+    }
+}
+
+
+void
+DirectoryPathDelegate::openFileDialogForEditor
+(QWidget *editor, const QModelIndex &index) const
+{
+    QPointer<QWidget> pathEditor(editor);
+    QFileDialog dialog(pathEditor.data());
+    dialog.setFileMode(QFileDialog::Directory);
+    dialog.setOption(QFileDialog::ShowDirsOnly, true);
+    dialog.setOption(QFileDialog::DontUseNativeDialog, true);
+
+    if (dialog.exec() == QDialog::Accepted) {
+        // Check if the editor widget still exists before using it
+        if (!pathEditor.isNull()) {
+            QString selectedDir = dialog.selectedFiles().first();
+            // Write directly to the model - this persists the data
+            QAbstractItemModel *model = const_cast<QAbstractItemModel*>(index.model());
+            model->setData(index, selectedDir, Qt::EditRole);
+        }
+    }
+
+    // The editor might have been destroyed during dialog.exec().
+    // Schedule the closeEditor call to happen safely in the event loop.
+    if (!pathEditor.isNull()) {
+        QTimer::singleShot(0, const_cast<DirectoryPathDelegate*>(this), [this, pathEditor]() {
+            if (!pathEditor.isNull()) {
+                const_cast<DirectoryPathDelegate*>(this)->closeEditorForWidget(pathEditor.data());
+            }
+        });
+    }
+}
+#endif
+
 
 // ListEditWidget //////////////////////////////////////////////////////////////////////
 
@@ -534,7 +627,7 @@ ListEditWidget::ListEditWidget
 (QWidget *parent)
 : QWidget(parent)
 {
-    dialog = new QDialog(this);
+    dialog = new QDialog(parent);
     dialog->setModal(true);
 
     title = new QLabel();

src/Gui/StyledItemDelegates.h

@@ -145,20 +145,28 @@ class DirectoryPathWidget: public QWidget
 public:
     DirectoryPathWidget(QWidget *parent = nullptr);
 
-    void setPath(const QString &path);
     QString getPath() const;
     void setPlaceholderText(const QString &placeholder);
+    void setDelegateMode(bool delegateMode);
+
+public slots:
+    void setPath(const QString &path);
 
 signals:
-    void editingFinished();
+    void editingFinished(bool accepted);
+#ifdef Q_OS_MACOS
+    void browseRequested();
+#endif
 
 private:
-    QPushButton *openButton;
+    bool delegateMode = false;
+    QPushButton *browseButton;
     QLineEdit *lineEdit;
     bool lineEditAlreadyFinished = false;
 
 private slots:
-    void openDialog();
+    void handleBrowseClicked();
+    void openFileDialog();
     void lineEditFinished();
 };
 
@@ -179,12 +187,16 @@ public:
     void setMaxWidth(int maxWidth);
     void setPlaceholderText(const QString &placeholderText);
 
-private slots:
-    void commitAndCloseEditor();
-
 private:
     int maxWidth = -1;
     QString placeholderText;
+#ifdef Q_OS_MACOS
+    void closeEditorForWidget(QWidget *editor);
+    void openFileDialogForEditor(QWidget *editor, const QModelIndex &index) const;
+#endif
+
+private slots:
+    void onEditingFinished(bool accepted);
 };