[FEATURE] Duplicate map layer(s)

- Action available in Layer menu and legend contextual menu
- Layer style copy/pasted to duplicate
- Memory and plugin layers skipped
- Add sip binding to action in app interface

Author: dakcarto

python/gui/qgisinterface.sip

@@ -364,6 +364,8 @@ class QgisInterface : QObject
     virtual QAction *actionLayerSaveAs() = 0;
     virtual QAction *actionLayerSelectionSaveAs() = 0;
     virtual QAction *actionRemoveLayer() = 0;
+    /** @note added in 2.0 */
+    virtual QAction *actionDuplicateLayer() = 0;
     virtual QAction *actionLayerProperties() = 0;
     virtual QAction *actionLayerSeparator2() = 0 /Deprecated/;
     virtual QAction *actionAddToOverview() = 0;

src/app/legend/qgslegendlayer.cpp

@@ -430,6 +430,9 @@ void QgsLegendLayer::addToPopupMenu( QMenu& theMenu )
   // remove from canvas
   theMenu.addAction( QgsApplication::getThemeIcon( "/mActionRemoveLayer.png" ), tr( "&Remove" ), QgisApp::instance(), SLOT( removeLayer() ) );
 
+  // duplicate layer
+  theMenu.addAction( QgsApplication::getThemeIcon( "/mActionAddMap.png" ), tr( "&Duplicate" ), QgisApp::instance(), SLOT( duplicateLayers() ) );
+
   // set layer crs
   theMenu.addAction( QgsApplication::getThemeIcon( "/mActionSetCRS.png" ), tr( "&Set Layer CRS" ), QgisApp::instance(), SLOT( setLayerCRS() ) );
 

src/app/qgisapp.cpp

@@ -961,6 +961,7 @@ void QgisApp::createActions()
   connect( mActionLayerSaveAs, SIGNAL( triggered() ), this, SLOT( saveAsFile() ) );
   connect( mActionLayerSelectionSaveAs, SIGNAL( triggered() ), this, SLOT( saveSelectionAsVectorFile() ) );
   connect( mActionRemoveLayer, SIGNAL( triggered() ), this, SLOT( removeLayer() ) );
+  connect( mActionDuplicateLayer, SIGNAL( triggered() ), this, SLOT( duplicateLayers() ) );
   connect( mActionSetLayerCRS, SIGNAL( triggered() ), this, SLOT( setLayerCRS() ) );
   connect( mActionSetProjectCRSFromLayer, SIGNAL( triggered() ), this, SLOT( setProjectCRSFromLayer() ) );
   connect( mActionLayerProperties, SIGNAL( triggered() ), this, SLOT( layerProperties() ) );
@@ -1630,6 +1631,7 @@ void QgisApp::setTheme( QString theThemeName )
   mActionAddMssqlLayer->setIcon( QgsApplication::getThemeIcon( "/mActionAddMssqlLayer.png" ) );
 #endif
   mActionRemoveLayer->setIcon( QgsApplication::getThemeIcon( "/mActionRemoveLayer.png" ) );
+  mActionDuplicateLayer->setIcon( QgsApplication::getThemeIcon( "/mActionAddMap.png" ) );
   mActionSetLayerCRS->setIcon( QgsApplication::getThemeIcon( "/mActionSetLayerCRS.png" ) );
   mActionSetProjectCRSFromLayer->setIcon( QgsApplication::getThemeIcon( "/mActionSetProjectCRSFromLayer.png" ) );
   mActionNewVectorLayer->setIcon( QgsApplication::getThemeIcon( "/mActionNewVectorLayer.png" ) );
@@ -5341,6 +5343,77 @@ void QgisApp::removeLayer()
   mMapCanvas->refresh();
 }
 
+void QgisApp::duplicateLayers( QList<QgsMapLayer *> lyrList )
+{
+  if ( mMapCanvas && mMapCanvas->isDrawing() )
+  {
+    return;
+  }
+
+  if ( !mMapLegend )
+  {
+    return;
+  }
+
+  QList<QgsMapLayer *> selectedLyrs = lyrList.empty() ? mMapLegend->selectedLayers() : lyrList;
+  if ( selectedLyrs.empty() )
+  {
+    return;
+  }
+
+  mMapCanvas->freeze();
+  QgsMapLayer *dupLayer;
+  foreach ( QgsMapLayer * selectedLyr, selectedLyrs )
+  {
+    dupLayer = 0;
+    QString layerDupName = selectedLyr->name() + " " + tr( "copy" );
+
+    // duplicate the layer's basic parameters
+
+    QgsVectorLayer *vlayer = qobject_cast<QgsVectorLayer*>( selectedLyr );
+    // TODO: check for other layer types that won't duplicate correctly
+    // currently memory and plugin layers are skipped
+    if ( vlayer && vlayer->storageType() != "Memory storage" )
+    {
+      dupLayer = new QgsVectorLayer( vlayer->source(), layerDupName, vlayer->providerType() );
+    }
+
+    if ( !dupLayer )
+    {
+      QgsRasterLayer *rlayer = qobject_cast<QgsRasterLayer*>( selectedLyr );
+      if ( rlayer )
+      {
+        dupLayer = new QgsRasterLayer( rlayer->source(), layerDupName );
+      }
+    }
+
+    if ( dupLayer && !dupLayer->isValid() )
+    {
+      QgsDebugMsg( "Duplicated layer was invalid" );
+      continue;
+    }
+
+    if ( !dupLayer )
+    {
+      QMessageBox::information( this,
+                                tr( "Unsupported Layer" ),
+                                tr( "%1\n\nDuplication of layer type is unsupported." ).arg( selectedLyr->name() ) );
+      continue;
+    }
+
+    // add layer to project and layer registry
+    addMapLayer( dupLayer );
+
+    // duplicate the layer style
+    copyStyle( selectedLyr );
+    pasteStyle( dupLayer );
+  }
+
+  dupLayer = 0;
+  mMapCanvas->freeze( false );
+  mMapCanvas->refresh();
+}
+
 void QgisApp::setLayerCRS()
 {
   if ( mMapCanvas && mMapCanvas->isDrawing() )
@@ -6833,6 +6906,7 @@ void QgisApp::selectionChanged( QgsMapLayer *layer )
 void QgisApp::legendLayerSelectionChanged( void )
 {
   mActionRemoveLayer->setEnabled( mMapLegend && mMapLegend->selectedLayers().size() > 0 );
+  mActionDuplicateLayer->setEnabled( mMapLegend && mMapLegend->selectedLayers().size() > 0 );
   mActionSetLayerCRS->setEnabled( mMapLegend && mMapLegend->selectedLayers().size() > 0 );
   mActionSetProjectCRSFromLayer->setEnabled( mMapLegend && mMapLegend->selectedLayers().size() == 1 );
 }

src/app/qgisapp.h

@@ -290,6 +290,8 @@ class QgisApp : public QMainWindow, private Ui::MainWindow
     QAction *actionLayerSaveAs() { return mActionLayerSaveAs; }
     QAction *actionLayerSelectionSaveAs() { return mActionLayerSelectionSaveAs; }
     QAction *actionRemoveLayer() { return mActionRemoveLayer; }
+    /** @note added in 2.0 */
+    QAction *actionDuplicateLayer() { return mActionDuplicateLayer; }
     QAction *actionSetLayerCRS() { return mActionSetLayerCRS; }
     QAction *actionSetProjectCRSFromLayer() { return mActionSetProjectCRSFromLayer; }
     QAction *actionLayerProperties() { return mActionLayerProperties; }
@@ -543,6 +545,9 @@ class QgisApp : public QMainWindow, private Ui::MainWindow
     void userCenter();
     //! Remove a layer from the map and legend
     void removeLayer();
+    /** Duplicate map layer(s) in legend
+     * @note added in 2.0 */
+    void duplicateLayers( const QList<QgsMapLayer *> lyrList = QList<QgsMapLayer *>() );
     //! Set CRS of a layer
     void setLayerCRS();
     //! Assign layer CRS to project

src/app/qgisappinterface.cpp

@@ -465,6 +465,7 @@ QAction *QgisAppInterface::actionToggleEditing() { return qgis->actionToggleEdit
 QAction *QgisAppInterface::actionLayerSaveAs() { return qgis->actionLayerSaveAs(); }
 QAction *QgisAppInterface::actionLayerSelectionSaveAs() { return qgis->actionLayerSelectionSaveAs(); }
 QAction *QgisAppInterface::actionRemoveLayer() { return qgis->actionRemoveLayer(); }
+QAction *QgisAppInterface::actionDuplicateLayer() { return qgis->actionDuplicateLayer(); }
 QAction *QgisAppInterface::actionLayerProperties() { return qgis->actionLayerProperties(); }
 QAction *QgisAppInterface::actionLayerSeparator2() { return 0; }
 QAction *QgisAppInterface::actionAddToOverview() { return qgis->actionAddToOverview(); }

src/app/qgisappinterface.h

@@ -313,6 +313,8 @@ class QgisAppInterface : public QgisInterface
     virtual QAction *actionLayerSaveAs();
     virtual QAction *actionLayerSelectionSaveAs();
     virtual QAction *actionRemoveLayer();
+    /** @note added in 2.0 */
+    virtual QAction *actionDuplicateLayer();
     virtual QAction *actionLayerProperties();
     virtual QAction *actionLayerSeparator2();
     virtual QAction *actionAddToOverview();

src/gui/qgisinterface.h

@@ -466,6 +466,8 @@ class GUI_EXPORT QgisInterface : public QObject
     virtual QAction *actionLayerSaveAs() = 0;
     virtual QAction *actionLayerSelectionSaveAs() = 0;
     virtual QAction *actionRemoveLayer() = 0;
+    /** @note added in 2.0 */
+    virtual QAction *actionDuplicateLayer() = 0;
     virtual QAction *actionLayerProperties() = 0;
 #ifndef Q_MOC_RUN
     Q_DECL_DEPRECATED

src/ui/qgisapp.ui

@@ -168,6 +168,7 @@
     <addaction name="mActionLayerSaveAs"/>
     <addaction name="mActionLayerSelectionSaveAs"/>
     <addaction name="mActionRemoveLayer"/>
+    <addaction name="mActionDuplicateLayer"/>
     <addaction name="mActionSetLayerCRS"/>
     <addaction name="mActionSetProjectCRSFromLayer"/>
     <addaction name="mActionLayerProperties"/>
@@ -1821,6 +1822,18 @@ Acts on currently active editable layer</string>
     <string>Html Annotation</string>
    </property>
   </action>
+  <action name="mActionDuplicateLayer">
+   <property name="icon">
+    <iconset resource="../../images/images.qrc">
+     <normaloff>:/images/themes/default/mActionAddMap.png</normaloff>:/images/themes/default/mActionAddMap.png</iconset>
+   </property>
+   <property name="text">
+    <string>Duplicate Layer(s)</string>
+   </property>
+   <property name="toolTip">
+    <string>Duplicate Layer(s)</string>
+   </property>
+  </action>
  </widget>
  <resources>
   <include location="../../images/images.qrc"/>