QmlDesigner: Respect canBeContainer on drag from library to navigator

If the parent node can't be a container for the newly created node,
the newly created node is deleted within the same transaction.

Change-Id: I4f4771add3aae5b4509b3bb0a8fbabfed2e7c99e
Fixes: QDS-2660
Reviewed-by: Mahmoud Badri <mahmoud.badri@qt.io>
Reviewed-by: Thomas Hartmann <thomas.hartmann@qt.io>

src/plugins/qmldesigner/components/navigator/navigatortreemodel.cpp

@@ -557,9 +557,10 @@ void NavigatorTreeModel::handleItemLibraryItemDrop(const QMimeData *mimeData, in
     bool moveNodesAfter = true;
 
     if (foundTarget) {
-        if (!NodeHints::fromItemLibraryEntry(itemLibraryEntry).canBeDroppedInNavigator())
+        if (!hints.canBeDroppedInNavigator())
             return;
 
+        bool validContainer = false;
         QmlObjectNode newQmlObjectNode;
         m_view->executeInTransaction("NavigatorTreeModel::handleItemLibraryItemDrop", [&] {
             newQmlObjectNode = QmlItemNode::createQmlObjectNode(m_view, itemLibraryEntry, QPointF(), targetProperty, false);
@@ -587,6 +588,7 @@ void NavigatorTreeModel::handleItemLibraryItemDrop(const QMimeData *mimeData, in
                     ModelNode targetEnv;
                     if (targetProperty.parentModelNode().isSubclassOf("QtQuick3D.SceneEnvironment")) {
                         targetEnv = targetProperty.parentModelNode();
+                        validContainer = true;
                     } else if (targetProperty.parentModelNode().isSubclassOf("QtQuick3D.View3D")) {
                         // see if View3D has environment set to it
                         BindingProperty envNodeProp = targetProperty.parentModelNode().bindingProperty("environment");
@@ -595,6 +597,7 @@ void NavigatorTreeModel::handleItemLibraryItemDrop(const QMimeData *mimeData, in
                             if (envNode.isValid())
                                 targetEnv = envNode;
                         }
+                        validContainer = true;
                     }
                     insertIntoList("effects", targetEnv);
                 } else if (newModelNode.isSubclassOf("QtQuick3D.Material")) {
@@ -603,6 +606,7 @@ void NavigatorTreeModel::handleItemLibraryItemDrop(const QMimeData *mimeData, in
                         ModelNode targetModel;
                         targetModel = targetProperty.parentModelNode();
                         insertIntoList("materials", targetModel);
+                        validContainer = true;
                     }
                 } else {
                     const bool isShader = newModelNode.isSubclassOf("QtQuick3D.Shader");
@@ -627,13 +631,20 @@ void NavigatorTreeModel::handleItemLibraryItemDrop(const QMimeData *mimeData, in
                                 // want undo to place the node under invalid parent
                                 moveNodesAfter = false;
                                 moveNodesInteractive(targetProperty, {newQmlObjectNode}, targetRowNumber, false);
+                                validContainer = true;
                             }
                         }
                     }
                 }
+                if (!validContainer) {
+                    validContainer = NodeHints::fromModelNode(targetProperty.parentModelNode()).canBeContainerFor(newModelNode);
+                    if (!validContainer)
+                        newQmlObjectNode.destroy();
+                }
             }
         });
 
+        if (validContainer) {
             if (moveNodesAfter && newQmlObjectNode.isValid() && targetProperty.isNodeListProperty()) {
                 QList<ModelNode> newModelNodeList;
                 newModelNodeList.append(newQmlObjectNode);
@@ -644,6 +655,7 @@ void NavigatorTreeModel::handleItemLibraryItemDrop(const QMimeData *mimeData, in
             if (newQmlObjectNode.isValid())
                 m_view->setSelectedModelNode(newQmlObjectNode.modelNode());
         }
+    }
 }
 
 void NavigatorTreeModel::handleItemLibraryImageDrop(const QMimeData *mimeData, int rowNumber, const QModelIndex &dropModelIndex)
@@ -717,9 +729,14 @@ void NavigatorTreeModel::handleItemLibraryImageDrop(const QMimeData *mimeData, i
             // if dropping an image on a texture, set the texture source
             targetNode.variantProperty("source").setValue(imagePath);
         } else {
-
+            m_view->executeInTransaction("NavigatorTreeModel::handleItemLibraryImageDrop", [&] {
                 // create an image
-            newModelNode = QmlItemNode::createQmlItemNodeFromImage(m_view, imageSource , QPointF(), targetProperty);
+                QmlItemNode newItemNode = QmlItemNode::createQmlItemNodeFromImage(m_view, imageSource, QPointF(), targetProperty, false);
+                if (NodeHints::fromModelNode(targetProperty.parentModelNode()).canBeContainerFor(newItemNode.modelNode()))
+                    newModelNode = newItemNode.modelNode();
+                else
+                    newItemNode.destroy();
+            });
         }
 
         if (newModelNode.isValid()) {

src/plugins/qmldesigner/designercore/include/qmlitemnode.h

@@ -61,11 +61,13 @@ public:
     static QmlItemNode createQmlItemNodeFromImage(AbstractView *view,
                                                   const QString &imageName,
                                                   const QPointF &position,
-                                                  QmlItemNode parentQmlItemNode);
+                                                  QmlItemNode parentQmlItemNode,
+                                                  bool executeInTransaction = true);
     static QmlItemNode createQmlItemNodeFromImage(AbstractView *view,
                                                   const QString &imageName,
                                                   const QPointF &position,
-                                                  NodeAbstractProperty parentproperty);
+                                                  NodeAbstractProperty parentproperty,
+                                                  bool executeInTransaction = true);
 
     QList<QmlItemNode> children() const;
     QList<QmlObjectNode> resources() const;

src/plugins/qmldesigner/designercore/model/qmlitemnode.cpp

@@ -73,22 +73,21 @@ QmlItemNode QmlItemNode::createQmlItemNode(AbstractView *view,
     return QmlItemNode(createQmlObjectNode(view, itemLibraryEntry, position, parentQmlItemNode));
 }
 
-QmlItemNode QmlItemNode::createQmlItemNodeFromImage(AbstractView *view, const QString &imageName, const QPointF &position, QmlItemNode parentQmlItemNode)
+QmlItemNode QmlItemNode::createQmlItemNodeFromImage(AbstractView *view, const QString &imageName, const QPointF &position, QmlItemNode parentQmlItemNode, bool executeInTransaction)
 {
     if (!parentQmlItemNode.isValid())
         parentQmlItemNode = QmlItemNode(view->rootModelNode());
 
     NodeAbstractProperty parentProperty = parentQmlItemNode.defaultNodeAbstractProperty();
 
-    return QmlItemNode::createQmlItemNodeFromImage(view, imageName, position, parentProperty);
+    return QmlItemNode::createQmlItemNodeFromImage(view, imageName, position, parentProperty, executeInTransaction);
 }
 
-QmlItemNode QmlItemNode::createQmlItemNodeFromImage(AbstractView *view, const QString &imageName, const QPointF &position, NodeAbstractProperty parentproperty)
+QmlItemNode QmlItemNode::createQmlItemNodeFromImage(AbstractView *view, const QString &imageName, const QPointF &position, NodeAbstractProperty parentproperty, bool executeInTransaction)
 {
     QmlItemNode newQmlItemNode;
 
-    if (parentproperty.isValid() && view->model()->hasNodeMetaInfo("QtQuick.Image")) {
+    auto doCreateQmlItemNodeFromImage = [=, &newQmlItemNode, &parentproperty]() {
-        view->executeInTransaction("QmlItemNode::createQmlItemNodeFromImage", [=, &newQmlItemNode, &parentproperty](){
         NodeMetaInfo metaInfo = view->model()->metaInfo("QtQuick.Image");
         QList<QPair<PropertyName, QVariant> > propertyPairList;
         propertyPairList.append({PropertyName("x"), QVariant(qRound(position.x()))});
@@ -112,8 +111,12 @@ QmlItemNode QmlItemNode::createQmlItemNodeFromImage(AbstractView *view, const QS
         newQmlItemNode.modelNode().variantProperty("fillMode").setEnumeration("Image.PreserveAspectFit");
 
         Q_ASSERT(newQmlItemNode.isValid());
-        });
+    };
-    }
+
+    if (executeInTransaction)
+        view->executeInTransaction("QmlItemNode::createQmlItemNodeFromImage", doCreateQmlItemNodeFromImage);
+    else
+        doCreateQmlItemNodeFromImage();
 
     return newQmlItemNode;
 }