qmlpreview: fix crash

Change-Id: I862a02b24948435f700cf9284edb369a92ce584d
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>

1 files changed, 3 insertions, 3 deletions

diff --git a/src/plugins/qmlpreview/qmlpreviewplugin.cpp b/src/plugins/qmlpreview/qmlpreviewplugin.cpp
index 8803475d8a..d18b8c37b0 100644
--- a/src/plugins/qmlpreview/qmlpreviewplugin.cpp
+++ b/src/plugins/qmlpreview/qmlpreviewplugin.cpp
@@ -329,9 +329,9 @@ void QmlPreviewPlugin::previewCurrentFile()
 
 void QmlPreviewPluginPrivate::onEditorChanged(Core::IEditor *editor)
 {
-    if (m_lastEditor) {
-        Core::IDocument *doc = m_lastEditor->document();
-        disconnect(doc, &Core::IDocument::contentsChanged, this, &QmlPreviewPluginPrivate::setDirty);
+    if (m_lastEditor && m_lastEditor->document()) {
+        disconnect(m_lastEditor->document(), &Core::IDocument::contentsChanged,
+                   this, &QmlPreviewPluginPrivate::setDirty);
         if (m_dirty) {
             m_dirty = false;
             checkEditor();