QmlDesigner: Choose proper default signal

Change-Id: I2a9493d0cc2a49afd624d58b53df54686d827422
Reviewed-by: Henning Gründl <henning.gruendl@qt.io>

src/plugins/qmldesigner/components/connectioneditor/connectionmodel.cpp

@@ -303,6 +303,46 @@ ModelNode ConnectionModel::getTargetNodeForConnection(const ModelNode &connectio
     return result;
 }
 
+static QString addOnToSignalName(const QString &signal)
+{
+    QString ret = signal;
+    ret[0] = ret.at(0).toUpper();
+    ret.prepend("on");
+    return ret;
+}
+
+static PropertyName getFirstSignalForTarget(const NodeMetaInfo &target)
+{
+    PropertyName ret = "clicked";
+
+    if (!target.isValid())
+        return ret;
+
+    const auto signalNames = target.signalNames();
+    if (signalNames.isEmpty())
+        return ret;
+
+    const PropertyNameList priorityList = {"clicked",
+                                           "toggled",
+                                           "started",
+                                           "stopped",
+                                           "moved",
+                                           "valueChanged",
+                                           "visualPostionChanged",
+                                           "accepted",
+                                           "currentIndexChanged",
+                                           "activeFocusChanged"};
+
+    for (const auto &signal : priorityList) {
+        if (signalNames.contains(signal))
+            return signal;
+    }
+
+    ret = target.signalNames().first();
+
+    return ret;
+}
+
 void ConnectionModel::addConnection()
 {
     QmlDesignerPlugin::emitUsageStatistics(Constants::EVENT_CONNECTION_ADDED);
@@ -314,8 +354,16 @@ void ConnectionModel::addConnection()
         NodeMetaInfo nodeMetaInfo = connectionView()->model()->qtQuickConnectionsMetaInfo();
 
         if (nodeMetaInfo.isValid()) {
-            connectionView()->executeInTransaction("ConnectionModel::addConnection", [=, &rootModelNode](){
+            ModelNode selectedNode = connectionView()->selectedModelNodes().constFirst();
-                ModelNode newNode = connectionView()->createModelNode("QtQuick.Connections",
+            const PropertyName signalHandlerName = addOnToSignalName(
+                                                       QString::fromUtf8(getFirstSignalForTarget(
+                                                           selectedNode.metaInfo())))
+                                                       .toUtf8();
+
+            connectionView()
+                ->executeInTransaction("ConnectionModel::addConnection", [=, &rootModelNode]() {
+                    ModelNode newNode = connectionView()
+                                            ->createModelNode("QtQuick.Connections",
                                                               nodeMetaInfo.majorVersion(),
                                                               nodeMetaInfo.minorVersion());
                     QString source = "console.log(\"clicked\")";
@@ -325,21 +373,26 @@ void ConnectionModel::addConnection()
                         if (QmlItemNode::isValidQmlItemNode(selectedNode))
                             selectedNode.nodeAbstractProperty("data").reparentHere(newNode);
                         else
-                        rootModelNode.nodeAbstractProperty(rootModelNode.metaInfo().defaultPropertyName()).reparentHere(newNode);
+                            rootModelNode
+                                .nodeAbstractProperty(rootModelNode.metaInfo().defaultPropertyName())
+                                .reparentHere(newNode);
 
-                    if (QmlItemNode(selectedNode).isFlowActionArea() || QmlVisualNode(selectedNode).isFlowTransition())
+                        if (QmlItemNode(selectedNode).isFlowActionArea()
+                            || QmlVisualNode(selectedNode).isFlowTransition())
                             source = selectedNode.validId() + ".trigger()";
 
                         if (!connectionView()->selectedModelNodes().constFirst().id().isEmpty())
                             newNode.bindingProperty("target").setExpression(selectedNode.validId());
                     } else {
-                    rootModelNode.nodeAbstractProperty(rootModelNode.metaInfo().defaultPropertyName()).reparentHere(newNode);
+                        rootModelNode
+                            .nodeAbstractProperty(rootModelNode.metaInfo().defaultPropertyName())
+                            .reparentHere(newNode);
                         newNode.bindingProperty("target").setExpression(rootModelNode.validId());
                     }
 
-                newNode.signalHandlerProperty("onClicked").setSource(source);
+                    newNode.signalHandlerProperty(signalHandlerName).setSource(source);
 
-                selectProperty(newNode.signalHandlerProperty("onClicked"));
+                    selectProperty(newNode.signalHandlerProperty(signalHandlerName));
                 });
         }
     }
@@ -790,14 +843,6 @@ QString removeOnFromSignalName(const QString &signal)
     return ret;
 }
 
-QString addOnToSignalName(const QString &signal)
-{
-    QString ret = signal;
-    ret[0] = ret.at(0).toUpper();
-    ret.prepend("on");
-    return ret;
-}
-
 void ConnectionModelBackendDelegate::setCurrentRow(int i)
 {
     if (m_currentRow == i)