QmlDesigner: Add helper functions to remove transitions

Change-Id: I33c972f9080b5c344e07c3f910e0a36fa981063b
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>

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

@@ -144,6 +144,7 @@ public:
     QmlFlowViewNode flowView() const;
     ModelNode findSourceForDecisionNode() const;
     static bool isFlowEditorTarget(const ModelNode &modelNode);
+    void removeTransitions();
 };
 
 class QMLDESIGNERCORE_EXPORT QmlFlowActionAreaNode : public QmlItemNode
@@ -181,6 +182,8 @@ public:
     const QList<ModelNode> wildcards() const;
     const QList<ModelNode> decicions() const;
     QList<ModelNode> transitionsForTarget(const ModelNode &modelNode);
+    void removeDanglingTransitions();
+    void removeAllTransitions();
 };
 
 

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

@@ -715,6 +715,14 @@ QList<ModelNode> QmlFlowViewNode::transitionsForTarget(const ModelNode &modelNod
     return list;
 }
 
+void QmlFlowViewNode::removeDanglingTransitions()
+{
+    for (const ModelNode &transition : transitions()) {
+        if (!transition.hasBindingProperty("to"))
+            QmlObjectNode(transition).destroy();
+    }
+}
+
 bool QmlFlowTargetNode::isValid() const
 {
      return isFlowEditorTarget(modelNode());
@@ -802,4 +810,24 @@ bool QmlFlowTargetNode::isFlowEditorTarget(const ModelNode &modelNode)
             || QmlVisualNode::isFlowWildcard(modelNode);
 }
 
+void QmlFlowTargetNode::removeTransitions()
+{
+    if (!modelNode().hasId())
+        return;
+
+    for (const BindingProperty &property : BindingProperty::findAllReferencesTo(modelNode())) {
+        if (property.isValid() && QmlVisualNode::isFlowTransition(property.parentModelNode()))
+                QmlObjectNode(property.parentModelNode()).destroy();
+    }
+}
+
+void QmlFlowViewNode::removeAllTransitions()
+{
+    if (!isValid())
+        return;
+
+    if (hasProperty("flowTransitions"))
+        removeProperty("flowTransitions");
+}
+
 } //QmlDesigner