ListModelEditor: Prevent adding qml keywords as a property name

Qml keywords shouldn't be used a property name for the list elements.
Also the user can't add an existing property name.

Fixes: QDS-15121
Change-Id: I3886ddfffe4013f8a92c53e1a126e46c40ebccde
Reviewed-by: Miikka Heikkinen <miikka.heikkinen@qt.io>
Reviewed-by: Marco Bubke <marco.bubke@qt.io>

src/plugins/qmldesigner/CMakeLists.txt

@@ -496,6 +496,7 @@ extend_qtc_plugin(QmlDesigner
   SOURCES
     listmodeleditordialog.cpp listmodeleditordialog.h
     listmodeleditormodel.cpp listmodeleditormodel.h
+    listmodeleditorpropertydialog.cpp listmodeleditorpropertydialog.h
 )
 
 extend_qtc_plugin(QmlDesigner

src/plugins/qmldesigner/components/listmodeleditor/listmodeleditordialog.cpp

@@ -2,10 +2,12 @@
 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
 
 #include "listmodeleditordialog.h"
-#include "listmodeleditormodel.h"
 
-#include <theme.h>
+#include "listmodeleditormodel.h"
+#include "listmodeleditorpropertydialog.h"
+
 #include <qmldesignericons.h>
+#include <theme.h>
 
 #include <coreplugin/icore.h>
 #include <utils/algorithm.h>
@@ -123,10 +125,14 @@ void ListModelEditorDialog::addRowBelow()
 
 void ListModelEditorDialog::openColumnDialog()
 {
-    bool ok;
-    QString columnName = QInputDialog::getText(
-        this, tr("Add Property"), tr("Property name:"), QLineEdit::Normal, "", &ok);
-    if (ok && !columnName.isEmpty())
+    ListModelEditorPropertyDialog propertyDialog{m_model->propertyNames()};
+    int result = propertyDialog.exec();
+
+    if (result != QDialog::Accepted)
+        return;
+
+    const QString columnName = propertyDialog.propertyName();
+    if (!columnName.isEmpty())
         m_model->addColumn(columnName);
 }
 

src/plugins/qmldesigner/components/listmodeleditor/listmodeleditordialog.h

@@ -7,8 +7,8 @@
 
 QT_BEGIN_NAMESPACE
 class QAbstractItemModel;
-class QTableView;
 class QModelIndex;
+class QTableView;
 QT_END_NAMESPACE
 
 namespace Ui {

src/plugins/qmldesigner/components/listmodeleditor/listmodeleditorpropertydialog.cpp

@@ -0,0 +1,78 @@
+// Copyright (C) 2025 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
+
+#include "listmodeleditorpropertydialog.h"
+
+#include <modelutils.h>
+#include <theme.h>
+
+#include <QDialogButtonBox>
+#include <QLabel>
+#include <QLayout>
+#include <QLineEdit>
+#include <QPushButton>
+#include <QRegularExpressionValidator>
+#include <QSpacerItem>
+
+namespace QmlDesigner {
+
+ListModelEditorPropertyDialog::ListModelEditorPropertyDialog(const PropertyNameList &existingProperties)
+    : QDialog()
+    , m_existingProperties(existingProperties)
+    , m_lineEdit(new QLineEdit(this))
+    , m_errorLabel(new QLabel(this))
+{
+    static const QRegularExpression propertyNameRegex{R"(^[a-z_]{1}\w+$)"};
+
+    QLabel *propertyLabel = new QLabel(tr("Property name:"), this);
+    m_lineEdit->setValidator(new QRegularExpressionValidator(propertyNameRegex, this));
+    connect(m_lineEdit,
+            &QLineEdit::textChanged,
+            this,
+            &ListModelEditorPropertyDialog::secondaryValidation);
+
+    QDialogButtonBox *dialogButtons = new QDialogButtonBox(this);
+    m_okButton = dialogButtons->addButton(QDialogButtonBox::Ok);
+    dialogButtons->addButton(QDialogButtonBox::Cancel);
+    connect(dialogButtons, &QDialogButtonBox::accepted, this, &QDialog::accept);
+    connect(dialogButtons, &QDialogButtonBox::rejected, this, &QDialog::reject);
+
+    m_errorLabel->setStyleSheet(
+        QString("color: %1").arg(Theme::getColor(Theme::DSwarningColor).name()));
+
+    QVBoxLayout *dialogLayout = new QVBoxLayout(this);
+    dialogLayout->addWidget(propertyLabel);
+    dialogLayout->addWidget(m_lineEdit);
+    dialogLayout->addWidget(m_errorLabel);
+    dialogLayout->addSpacerItem(
+        new QSpacerItem{1, 10, QSizePolicy::Minimum, QSizePolicy::MinimumExpanding});
+    dialogLayout->addWidget(dialogButtons);
+
+    setWindowTitle(tr("Add property"));
+    setError({});
+}
+
+QString ListModelEditorPropertyDialog::propertyName() const
+{
+    return m_lineEdit->text();
+}
+
+void ListModelEditorPropertyDialog::secondaryValidation(const QString &text)
+{
+    if (ModelUtils::isQmlKeyword(text))
+        setError(tr("`%1` is a QML keyword and can't be used as a property name.").arg(text));
+    else if (m_existingProperties.contains(text.toUtf8()))
+        setError(tr("`%1` already exists in the property list.").arg(text));
+    else
+        setError({});
+}
+
+void ListModelEditorPropertyDialog::setError(const QString &errorString)
+{
+    const bool hasError = !errorString.isEmpty();
+    const bool nameIsEmpty = propertyName().isEmpty();
+    m_errorLabel->setText(errorString);
+    m_okButton->setEnabled(!hasError && !nameIsEmpty);
+}
+
+} // namespace QmlDesigner

src/plugins/qmldesigner/components/listmodeleditor/listmodeleditorpropertydialog.h

@@ -0,0 +1,36 @@
+// Copyright (C) 2025 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
+
+#pragma once
+
+#include <nodeinstanceglobal.h>
+
+#include <QDialog>
+
+QT_BEGIN_NAMESPACE
+class QLabel;
+class QLineEdit;
+class QPushButton;
+QT_END_NAMESPACE
+
+namespace QmlDesigner {
+
+class ListModelEditorPropertyDialog : public QDialog
+{
+    Q_OBJECT
+
+public:
+    ListModelEditorPropertyDialog(const PropertyNameList &existingProperties);
+    QString propertyName() const;
+
+private:
+    void secondaryValidation(const QString &text);
+    void setError(const QString &errorString);
+
+    const PropertyNameList m_existingProperties;
+    QLineEdit *m_lineEdit = nullptr;
+    QLabel *m_errorLabel = nullptr;
+    QPushButton *m_okButton = nullptr;
+};
+
+} // namespace QmlDesigner