Handle active (current) layer in layer tree view

qgis · May 21, 2014 · a6158d5 · a6158d5
1 parent 1906de1
commit a6158d5
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Showing 2 changed files with 40 additions and 2 deletions.
diff --git a/src/gui/layertree/qgslayertreeview.cpp b/src/gui/layertree/qgslayertreeview.cpp
@@ -6,8 +6,9 @@
 #include <QMenu>
 #include <QContextMenuEvent>
 
-QgsLayerTreeView::QgsLayerTreeView(QWidget *parent) :
-  QTreeView(parent)
+QgsLayerTreeView::QgsLayerTreeView(QWidget *parent)
+  : QTreeView(parent)
+  , mCurrentLayer(0)
 {
   setHeaderHidden(true);
 
@@ -19,6 +20,7 @@ QgsLayerTreeView::QgsLayerTreeView(QWidget *parent) :
 
   connect(this, SIGNAL(collapsed(QModelIndex)), this, SLOT(updateExpandedStateToNode(QModelIndex)));
   connect(this, SIGNAL(expanded(QModelIndex)), this, SLOT(updateExpandedStateToNode(QModelIndex)));
+  connect(this, SIGNAL(currentChanged(QModelIndex,QModelIndex)), this, SLOT(onCurrentChanged(QModelIndex)));
 }
 
 void QgsLayerTreeView::setModel(QAbstractItemModel* model)
@@ -38,6 +40,20 @@ QgsLayerTreeModel *QgsLayerTreeView::layerTreeModel()
   return qobject_cast<QgsLayerTreeModel*>(model());
 }
 
+QgsMapLayer* QgsLayerTreeView::currentLayer() const
+{
+  return mCurrentLayer;
+}
+
+void QgsLayerTreeView::setCurrentLayer(QgsMapLayer* layer)
+{
+  if (mCurrentLayer == layer)
+    return;
+
+  mCurrentLayer = layer;
+  emit currentLayerChanged(mCurrentLayer);
+}
+
 
 void QgsLayerTreeView::contextMenuEvent(QContextMenuEvent *event)
 {
@@ -144,6 +160,19 @@ void QgsLayerTreeView::updateExpandedStateToNode(QModelIndex index)
   node->setExpanded(isExpanded(index));
 }
 
+void QgsLayerTreeView::onCurrentChanged(QModelIndex current)
+{
+  QgsLayerTreeNode* node = layerTreeModel()->index2node(current);
+  if (!node)
+    return; // TODO: maybe also support symbology nodes
+
+  QgsMapLayer* layer = 0;
+  if (node->nodeType() == QgsLayerTreeNode::NodeLayer)
+    layer = static_cast<QgsLayerTreeLayer*>(node)->layer();
+
+  setCurrentLayer(layer);
+}
+
 void QgsLayerTreeView::updateExpandedStateFromNode(QgsLayerTreeNode* node)
 {
   QModelIndex idx = layerTreeModel()->node2index(node);

diff --git a/src/gui/layertree/qgslayertreeview.h b/src/gui/layertree/qgslayertreeview.h
@@ -5,6 +5,7 @@
 
 class QgsLayerTreeModel;
 class QgsLayerTreeNode;
+class QgsMapLayer;
 
 class GUI_EXPORT QgsLayerTreeView : public QTreeView
 {
@@ -16,6 +17,9 @@ class GUI_EXPORT QgsLayerTreeView : public QTreeView
 
   QgsLayerTreeModel* layerTreeModel();
 
+  QgsMapLayer* currentLayer() const;
+  void setCurrentLayer(QgsMapLayer* layer);
+
 protected:
   void contextMenuEvent(QContextMenuEvent* event);
 
@@ -26,6 +30,7 @@ class GUI_EXPORT QgsLayerTreeView : public QTreeView
   void updateExpandedStateFromNode(QgsLayerTreeNode* node);
 
 signals:
+  void currentLayerChanged(QgsMapLayer* layer);
 
 public slots:
 
@@ -38,6 +43,10 @@ protected slots:
 
   void updateExpandedStateToNode(QModelIndex index);
 
+  void onCurrentChanged(QModelIndex current);
+
+protected:
+  QgsMapLayer* mCurrentLayer;
 };
 
 #endif // QGSLAYERTREEVIEW_H