[FEATURE] Add composer pan action

src/app/composer/qgscomposer.cpp

@@ -144,6 +144,7 @@ QgsComposer::QgsComposer( QgisApp *qgis, const QString& title )
 
   QActionGroup* toggleActionGroup = new QActionGroup( this );
   toggleActionGroup->addAction( mActionMoveItemContent );
+  toggleActionGroup->addAction( mActionPan );
   toggleActionGroup->addAction( mActionAddNewMap );
   toggleActionGroup->addAction( mActionAddNewLabel );
   toggleActionGroup->addAction( mActionAddNewLegend );
@@ -166,6 +167,7 @@ QgsComposer::QgsComposer( QgisApp *qgis, const QString& title )
   mActionAddNewScalebar->setCheckable( true );
   mActionAddImage->setCheckable( true );
   mActionMoveItemContent->setCheckable( true );
+  mActionPan->setCheckable( true );
   mActionAddArrow->setCheckable( true );
 
 #ifdef Q_WS_MAC
@@ -1673,6 +1675,14 @@ void QgsComposer::on_mActionMoveItemContent_triggered()
   }
 }
 
+void QgsComposer::on_mActionPan_triggered()
+{
+  if ( mView )
+  {
+    mView->setCurrentTool( QgsComposerView::Pan );
+  }
+}
+
 void QgsComposer::on_mActionGroupItems_triggered()
 {
   if ( mView )

src/app/composer/qgscomposer.h

@@ -204,6 +204,9 @@ class QgsComposer: public QMainWindow, private Ui::QgsComposerBase
     //! Set tool to move item content
     void on_mActionMoveItemContent_triggered();
 
+    //! Set tool to move item content
+    void on_mActionPan_triggered();
+
     //! Group selected items
     void on_mActionGroupItems_triggered();
 
@@ -242,7 +245,7 @@ class QgsComposer: public QMainWindow, private Ui::QgsComposerBase
 
     //! Select next item below
     void on_mActionSelectNextAbove_triggered();
-    
+
     //! Select next item above
     void on_mActionSelectNextBelow_triggered();
 

src/gui/qgscomposerview.cpp

@@ -49,6 +49,7 @@ QgsComposerView::QgsComposerView( QWidget* parent, const char* name, Qt::WFlags
     , mPaintingEnabled( true )
     , mHorizontalRuler( 0 )
     , mVerticalRuler( 0 )
+    , mPanning( false )
 {
   Q_UNUSED( f );
   Q_UNUSED( name );
@@ -59,6 +60,29 @@ QgsComposerView::QgsComposerView( QWidget* parent, const char* name, Qt::WFlags
   setFrameShape( QFrame::NoFrame );
 }
 
+void QgsComposerView::setCurrentTool( QgsComposerView::Tool t )
+{
+  mCurrentTool = t;
+
+  //update mouse cursor for current tool
+  if ( !composition() )
+  {
+    return;
+  }
+  if ( t == QgsComposerView::Pan )
+  {
+    //lock cursor to prevent composer items changing it
+    composition()->setPreventCursorChange( true );
+    viewport()->setCursor( Qt::OpenHandCursor );
+  }
+  else
+  {
+    //not using pan tool, composer items can change cursor
+    composition()->setPreventCursorChange( false );
+    viewport()->setCursor( Qt::ArrowCursor );
+  }
+}
+
 void QgsComposerView::mousePressEvent( QMouseEvent* e )
 {
   if ( !composition() )
@@ -166,6 +190,15 @@ void QgsComposerView::mousePressEvent( QMouseEvent* e )
       break;
     }
 
+    case Pan:
+    {
+      //pan action
+      mPanning = true;
+      mMouseLastXY = e->pos();
+      viewport()->setCursor( Qt::ClosedHandCursor );
+      break;
+    }
+
     case MoveItemContent:
     {
       //get a list of items at clicked position
@@ -341,6 +374,27 @@ void QgsComposerView::mouseReleaseEvent( QMouseEvent* e )
 
   QPointF scenePoint = mapToScene( e->pos() );
 
+  if ( mPanning )
+  {
+    mPanning = false;
+
+    //set new cursor
+    if ( mCurrentTool == Pan )
+    {
+      viewport()->setCursor( Qt::OpenHandCursor );
+    }
+    else
+    {
+      if ( composition() )
+      {
+        //allow composer items to change cursor
+        composition()->setPreventCursorChange( false );
+      }
+      viewport()->setCursor( Qt::ArrowCursor );
+    }
+    return;
+  }
+
   switch ( mCurrentTool )
   {
     case Select:
@@ -444,6 +498,8 @@ void QgsComposerView::mouseMoveEvent( QMouseEvent* e )
     return;
   }
 
+  mMouseCurrentXY = e->pos();
+
   updateRulers();
   if ( mHorizontalRuler )
   {
@@ -454,7 +510,15 @@ void QgsComposerView::mouseMoveEvent( QMouseEvent* e )
     mVerticalRuler->updateMarker( e->posF() );
   }
 
-  if ( e->buttons() == Qt::NoButton )
+  if ( mPanning )
+  {
+    //panning, so scroll view
+    horizontalScrollBar()->setValue( horizontalScrollBar()->value() - ( e->x() - mMouseLastXY.x() ) );
+    verticalScrollBar()->setValue( verticalScrollBar()->value() - ( e->y() - mMouseLastXY.y() ) );
+    mMouseLastXY = e->pos();
+    return;
+  }
+  else if ( e->buttons() == Qt::NoButton )
   {
     if ( mCurrentTool == Select )
     {

src/gui/qgscomposerview.h

@@ -65,7 +65,8 @@ class GUI_EXPORT QgsComposerView: public QGraphicsView
       AddEllipse,
       AddTriangle,
       AddTable, //add attribute table
-      MoveItemContent //move content of item (e.g. content of map)
+      MoveItemContent, //move content of item (e.g. content of map)
+      Pan
     };
 
     enum ClipboardMode
@@ -108,7 +109,7 @@ class GUI_EXPORT QgsComposerView: public QGraphicsView
     void selectInvert();
 
     QgsComposerView::Tool currentTool() const {return mCurrentTool;}
-    void setCurrentTool( QgsComposerView::Tool t ) {mCurrentTool = t;}
+    void setCurrentTool( QgsComposerView::Tool t );
 
     /**Sets composition (derived from QGraphicsScene)*/
     void setComposition( QgsComposition* c );
@@ -167,6 +168,10 @@ class GUI_EXPORT QgsComposerView: public QGraphicsView
     /** Draw a shape on the canvas */
     void addShape( Tool currentTool );
 
+    bool mPanning;
+    QPoint mMouseLastXY;
+    QPoint mMouseCurrentXY;
+
     //void connectAddRemoveCommandSignals( QgsAddRemoveItemCommand* c );
 
   signals:

src/ui/qgscomposerbase.ui

@@ -96,6 +96,7 @@
    <attribute name="toolBarBreak">
     <bool>true</bool>
    </attribute>
+   <addaction name="mActionPan"/>
    <addaction name="mActionSelectMoveItem"/>
    <addaction name="mActionMoveItemContent"/>
    <addaction name="mActionGroupItems"/>
@@ -673,6 +674,15 @@
     <string>Ctrl+Alt+]</string>
    </property>
   </action>  
+  <action name="mActionPan">
+   <property name="icon">
+    <iconset resource="../../images/images.qrc">
+     <normaloff>:/images/themes/default/mActionPan.svg</normaloff>:/images/themes/default/mActionPan.svg</iconset>
+   </property>
+   <property name="text">
+    <string>Pan Composer</string>
+   </property>
+  </action>     
  </widget>
  <resources>
   <include location="../../images/images.qrc"/>