implement currentLayer() and setCurrentLayer() in QgsLegendInterface …

…to set/get current layer

python/gui/qgslegendinterface.sip

@@ -68,6 +68,17 @@ class QgsLegendInterface : QObject
      */
     virtual bool removeLegendLayerAction( QAction* action ) = 0;
 
+    //! Returns the current layer if the current item is a QgsLegendLayer.
+    //! If the current item is a QgsLegendLayer, its first maplayer is returned.
+    //! Else, 0 is returned.
+    //! @note Added in 2.0
+    virtual QgsMapLayer* currentLayer() = 0;
+
+    //! set the current layer
+    //! returns true if the layer exists, false otherwise
+    //! @note Added in 2.0
+    virtual bool setCurrentLayer( QgsMapLayer *layer ) = 0;
+
   signals:
 
     //! emitted when a group index has changed

src/app/legend/qgsapplegendinterface.cpp

@@ -30,6 +30,7 @@ QgsAppLegendInterface::QgsAppLegendInterface( QgsLegend * legend )
   connect( legend, SIGNAL( itemMovedGroup( QgsLegendItem *, int ) ), this, SIGNAL( groupRelationsChanged() ) );
   // connect( legend, SIGNAL( itemChanged( QTreeWidgetItem*, int ) ), this, SIGNAL( groupRelationsChanged() ) );
   connect( legend, SIGNAL( itemRemoved() ), this, SIGNAL( itemRemoved() ) );
+  connect( legend, SIGNAL( currentLayerChanged( QgsMapLayer * ) ), this, SIGNAL( currentLayerChanged( QgsMapLayer * ) ) );
 }
 
 QgsAppLegendInterface::~QgsAppLegendInterface()
@@ -208,3 +209,12 @@ bool QgsAppLegendInterface::removeLegendLayerAction( QAction* action )
   return mLegend->removeLegendLayerAction( action );
 }
 
+QgsMapLayer* QgsAppLegendInterface::currentLayer()
+{
+  return mLegend->currentLayer();
+}
+
+bool QgsAppLegendInterface::setCurrentLayer( QgsMapLayer *layer )
+{
+  return mLegend->setCurrentLayer( layer );
+}

src/app/legend/qgsapplegendinterface.h

@@ -72,6 +72,9 @@ class QgsAppLegendInterface : public QgsLegendInterface
     void addLegendLayerActionForLayer( QAction* action, QgsMapLayer* layer );
     bool removeLegendLayerAction( QAction* action );
 
+    QgsMapLayer* currentLayer();
+    bool setCurrentLayer( QgsMapLayer *layer );
+
   public slots:
 
     //! Add a new group

src/gui/qgslegendinterface.h

@@ -103,6 +103,17 @@ class GUI_EXPORT QgsLegendInterface : public QObject
      */
     virtual bool removeLegendLayerAction( QAction* action ) = 0;
 
+    //! Returns the current layer if the current item is a QgsLegendLayer.
+    //! If the current item is a QgsLegendLayer, its first maplayer is returned.
+    //! Else, 0 is returned.
+    //! @note Added in 2.0
+    virtual QgsMapLayer* currentLayer() = 0;
+
+    //! set the current layer
+    //! returns true if the layer exists, false otherwise
+    //! @note Added in 2.0
+    virtual bool setCurrentLayer( QgsMapLayer *layer ) = 0;
+
   signals:
 
     //! emitted when a group index has changed
@@ -117,6 +128,11 @@ class GUI_EXPORT QgsLegendInterface : public QObject
     /* //! emitted when an item (group/layer) is removed */
     void itemRemoved( );
 
+    //! Emitted whenever current (selected) layer changes
+    //  the pointer to layer can be null if no layer is selected
+    //! @note Added in 2.0
+    void currentLayerChanged( QgsMapLayer * layer );
+
   public slots:
 
     //! Add a new group