QmlDesigner.propertyEditor: crash fix

If the anchor target does not have a corresponding model node
we had a crash. This happens for e.g. Flickable because children
is redefined.


Task-number: QTCREATORBUG-5829
Change-Id: Ib3f609fe7c29778dd4fdd8ed1ac8526afbb36fe0
Reviewed-on: http://codereview.qt.nokia.com/3327
Reviewed-by: Marco Bubke <marco.bubke@nokia.com>
Reviewed-by: Thomas Hartmann <Thomas.Hartmann@nokia.com>

1 files changed, 60 insertions, 24 deletions

diff --git a/src/plugins/qmldesigner/components/propertyeditor/qmlanchorbindingproxy.cpp b/src/plugins/qmldesigner/components/propertyeditor/qmlanchorbindingproxy.cpp
index 41a01e0209..bb33ab26dc 100644
--- a/src/plugins/qmldesigner/components/propertyeditor/qmlanchorbindingproxy.cpp
+++ b/src/plugins/qmldesigner/components/propertyeditor/qmlanchorbindingproxy.cpp
@@ -82,23 +82,41 @@ void QmlAnchorBindingProxy::setup(const QmlItemNode &fxItemNode)
 
     m_verticalTarget = m_horizontalTarget = m_topTarget = m_bottomTarget = m_leftTarget = m_rightTarget = m_fxItemNode.modelNode().parentProperty().parentModelNode();
 
-    if (topAnchored())
-        m_topTarget = m_fxItemNode.anchors().instanceAnchor(AnchorLine::Top).qmlItemNode();
+    if (topAnchored()) {
+        ModelNode targetNode = m_fxItemNode.anchors().instanceAnchor(AnchorLine::Top).qmlItemNode();
+        if (targetNode.isValid())
+            m_topTarget = targetNode;
+    }
 
-    if (bottomAnchored())
-        m_bottomTarget = m_fxItemNode.anchors().instanceAnchor(AnchorLine::Bottom).qmlItemNode();
+    if (bottomAnchored()) {
+        ModelNode targetNode = m_fxItemNode.anchors().instanceAnchor(AnchorLine::Bottom).qmlItemNode();
+        if (targetNode.isValid())
+            m_bottomTarget = targetNode;
+    }
 
-    if (leftAnchored())
-        m_leftTarget = m_fxItemNode.anchors().instanceAnchor(AnchorLine::Left).qmlItemNode();
+    if (leftAnchored()) {
+        ModelNode targetNode = m_fxItemNode.anchors().instanceAnchor(AnchorLine::Left).qmlItemNode();
+        if (targetNode.isValid())
+            m_leftTarget = targetNode;
+    }
 
-    if (rightAnchored())
-        m_rightTarget = m_fxItemNode.anchors().instanceAnchor(AnchorLine::Right).qmlItemNode();
+    if (rightAnchored()) {
+        ModelNode targetNode = m_fxItemNode.anchors().instanceAnchor(AnchorLine::Right).qmlItemNode();
+        if (targetNode.isValid())
+            m_rightTarget = targetNode;
+    }
 
-    if (verticalCentered())
-        m_verticalTarget = m_fxItemNode.anchors().instanceAnchor(AnchorLine::VerticalCenter).qmlItemNode();
+    if (verticalCentered()) {
+        ModelNode targetNode = m_fxItemNode.anchors().instanceAnchor(AnchorLine::VerticalCenter).qmlItemNode();
+        if (targetNode.isValid())
+            m_verticalTarget = targetNode;
+    }
 
-    if (horizontalCentered())
-        m_horizontalTarget = m_fxItemNode.anchors().instanceAnchor(AnchorLine::HorizontalCenter).qmlItemNode();
+    if (horizontalCentered()) {
+        ModelNode targetNode = m_fxItemNode.anchors().instanceAnchor(AnchorLine::HorizontalCenter).qmlItemNode();
+        if (targetNode.isValid())
+            m_horizontalTarget = targetNode;
+    }
 
     emit itemNodeChanged();
     emit parentChanged();
@@ -130,23 +148,41 @@ void QmlAnchorBindingProxy::invalidate(const QmlItemNode &fxItemNode)
 
     m_verticalTarget = m_horizontalTarget = m_topTarget = m_bottomTarget = m_leftTarget = m_rightTarget = m_fxItemNode.modelNode().parentProperty().parentModelNode();
 
-    if (topAnchored())
-        m_topTarget = m_fxItemNode.anchors().instanceAnchor(AnchorLine::Top).qmlItemNode();
+    if (topAnchored()) {
+        ModelNode targetNode = m_fxItemNode.anchors().instanceAnchor(AnchorLine::Top).qmlItemNode();
+        if (targetNode.isValid())
+            m_topTarget = targetNode;
+    }
 
-    if (bottomAnchored())
-        m_bottomTarget = m_fxItemNode.anchors().instanceAnchor(AnchorLine::Bottom).qmlItemNode();
+    if (bottomAnchored()) {
+        ModelNode targetNode = m_fxItemNode.anchors().instanceAnchor(AnchorLine::Bottom).qmlItemNode();
+        if (targetNode.isValid())
+            m_bottomTarget = targetNode;
+    }
 
-    if (leftAnchored())
-        m_leftTarget = m_fxItemNode.anchors().instanceAnchor(AnchorLine::Left).qmlItemNode();
+    if (leftAnchored()) {
+        ModelNode targetNode = m_fxItemNode.anchors().instanceAnchor(AnchorLine::Left).qmlItemNode();
+        if (targetNode.isValid())
+            m_leftTarget = targetNode;
+    }
 
-    if (rightAnchored())
-        m_rightTarget = m_fxItemNode.anchors().instanceAnchor(AnchorLine::Right).qmlItemNode();
+    if (rightAnchored()) {
+        ModelNode targetNode = m_fxItemNode.anchors().instanceAnchor(AnchorLine::Right).qmlItemNode();
+        if (targetNode.isValid())
+            m_rightTarget = targetNode;
+    }
 
-    if (verticalCentered())
-        m_verticalTarget = m_fxItemNode.anchors().instanceAnchor(AnchorLine::VerticalCenter).qmlItemNode();
+    if (verticalCentered()) {
+        ModelNode targetNode = m_fxItemNode.anchors().instanceAnchor(AnchorLine::VerticalCenter).qmlItemNode();
+        if (targetNode.isValid())
+            m_verticalTarget = targetNode;
+    }
 
-    if (horizontalCentered())
-        m_horizontalTarget = m_fxItemNode.anchors().instanceAnchor(AnchorLine::HorizontalCenter).qmlItemNode();
+    if (horizontalCentered()) {
+        ModelNode targetNode = m_fxItemNode.anchors().instanceAnchor(AnchorLine::HorizontalCenter).qmlItemNode();
+        if (targetNode.isValid())
+            m_horizontalTarget = targetNode;
+    }
 
     emit topAnchorChanged();
     emit bottomAnchorChanged();