new map tool to select single feature

python/gui/gui.sip

@@ -74,6 +74,7 @@
 %Include qgsmaptool.sip
 %Include qgsmaptoolemitpoint.sip
 %Include qgsmaptoolidentify.sip
+%Include qgsmaptoolidentifyfeature.sip
 %Include qgsmaptoolpan.sip
 %Include qgsmaptooltouch.sip
 %Include qgsmaptoolzoom.sip

python/gui/qgsmaptoolidentify.sip

@@ -78,10 +78,6 @@ class QgsMapToolIdentify : QgsMapTool
     @return a list of IdentifyResult*/
     QList<QgsMapToolIdentify::IdentifyResult> identify( int x, int y, IdentifyMode mode, LayerType layerType = AllLayers );
 
-  protected:
-    //! rubber bands for layer select mode
-    void deleteRubberBands();
-
   public slots:
     void formatChanged( QgsRasterLayer *layer );
     void layerDestroyed();
@@ -90,4 +86,25 @@ class QgsMapToolIdentify : QgsMapTool
     void identifyProgress( int, int );
     void identifyMessage( QString );
     void changedRasterResults( QList<QgsMapToolIdentify::IdentifyResult>& );
+
+  protected:
+    //! rubber bands for layer select mode
+    void deleteRubberBands();
+
+    /** Performs the identification.
+    To avoid beeing forced to specify IdentifyMode with a list of layers
+    this has been made private and two publics methods are offered
+    @param x x coordinates of mouseEvent
+    @param y y coordinates of mouseEvent
+    @param mode Identification mode. Can use Qgis default settings or a defined mode.
+    @param layerList Performs the identification within the given list of layers.
+    @param layerType Only performs identification in a certain type of layers (raster, vector).
+    @return true if identification succeeded and a feature has been found, false otherwise.*/
+    QList<QgsMapToolIdentify::IdentifyResult> identify( int x, int y, IdentifyMode mode,  QList<QgsMapLayer*> layerList, LayerType layerType = AllLayers );
+
+    /** call the right method depending on layer type */
+    bool identifyLayer( QList<QgsMapToolIdentify::IdentifyResult> *results, QgsMapLayer *layer, QgsPoint point, QgsRectangle viewExtent, double mapUnitsPerPixel, LayerType layerType = AllLayers );
+
+    bool identifyRasterLayer( QList<QgsMapToolIdentify::IdentifyResult> *results, QgsRasterLayer *layer, QgsPoint point, QgsRectangle viewExtent, double mapUnitsPerPixel );
+    bool identifyVectorLayer( QList<QgsMapToolIdentify::IdentifyResult> *results, QgsVectorLayer *layer, QgsPoint point );
 };

python/gui/qgsmaptoolidentifyfeature.sip

@@ -0,0 +1,14 @@
+class QgsMapToolIdentifyFeature : QgsMapToolIdentify
+{
+%TypeHeaderCode
+#include <qgsmaptoolidentifyfeature.h>
+%End
+
+  public:
+    QgsMapToolIdentifyFeature( QgsVectorLayer* vl, QgsMapCanvas* canvas );
+
+    void canvasReleaseEvent( QMouseEvent* e );
+
+  signals:
+    void featureIdentified( QgsFeature );
+};

src/gui/CMakeLists.txt

@@ -181,6 +181,7 @@ qgsmaptip.cpp
 qgsmaptool.cpp
 qgsmaptoolemitpoint.cpp
 qgsmaptoolidentify.cpp
+qgsmaptoolidentifyfeature.cpp
 qgsmaptoolpan.cpp
 qgsmaptoolzoom.cpp
 qgsmessagebar.cpp
@@ -372,6 +373,7 @@ qgsmapoverviewcanvas.h
 qgsmaptool.h
 qgsmaptoolemitpoint.h
 qgsmaptoolidentify.h
+qgsmaptoolidentifyfeature.h
 qgsmessagebaritem.h
 qgsmessagebar.h
 qgsmessagelogviewer.h
@@ -454,6 +456,7 @@ qgsmaptip.h
 qgsmaptool.h
 qgsmaptoolemitpoint.h
 qgsmaptoolidentify.h
+qgsmaptoolidentifyfeature.h
 qgsmaptoolpan.h
 qgsmaptoolzoom.h
 qgsmessagebaritem.h

src/gui/qgsmaptool.cpp

@@ -85,6 +85,8 @@ void QgsMapTool::activate()
   // set cursor (map tools usually set it in constructor)
   mCanvas->setCursor( mCursor );
   QgsDebugMsg( "Cursor has been set" );
+
+  emit activated();
 }
 
 
@@ -94,6 +96,8 @@ void QgsMapTool::deactivate()
     mAction->setChecked( false );
   if ( mButton )
     mButton->setChecked( false );
+
+  emit deactivated();
 }
 
 void QgsMapTool::setAction( QAction* action )

src/gui/qgsmaptool.h

@@ -153,6 +153,12 @@ class GUI_EXPORT QgsMapTool : public QObject
     //! emit signal to clear previous message
     void messageDiscarded();
 
+    //! signal emitted once the map tool is activated
+    void activated();
+
+    //! signal emitted once the map tool is deactivated
+    void deactivated();
+
   private slots:
     //! clear pointer when action is destroyed
     void actionDestroyed();

src/gui/qgsmaptoolidentify.h

@@ -123,10 +123,6 @@ class GUI_EXPORT QgsMapToolIdentify : public QgsMapTool
     @return a list of IdentifyResult*/
     QList<IdentifyResult> identify( int x, int y, IdentifyMode mode, LayerType layerType = AllLayers );
 
-  protected:
-    //! rubber bands for layer select mode
-    void deleteRubberBands();
-
   public slots:
     void formatChanged( QgsRasterLayer *layer );
     void layerDestroyed();
@@ -136,7 +132,10 @@ class GUI_EXPORT QgsMapToolIdentify : public QgsMapTool
     void identifyMessage( QString );
     void changedRasterResults( QList<IdentifyResult>& );
 
-  private:
+  protected:
+    //! rubber bands for layer select mode
+    void deleteRubberBands();
+
     /** Performs the identification.
     To avoid beeing forced to specify IdentifyMode with a list of layers
     this has been made private and two publics methods are offered
@@ -154,6 +153,8 @@ class GUI_EXPORT QgsMapToolIdentify : public QgsMapTool
     bool identifyRasterLayer( QList<IdentifyResult> *results, QgsRasterLayer *layer, QgsPoint point, QgsRectangle viewExtent, double mapUnitsPerPixel );
     bool identifyVectorLayer( QList<IdentifyResult> *results, QgsVectorLayer *layer, QgsPoint point );
 
+
+  private:
     //! Private helper
     virtual void convertMeasurement( QgsDistanceArea &calc, double &measure, QGis::UnitType &u, bool isArea );
 

src/gui/qgsmaptoolidentifyfeature.cpp

@@ -0,0 +1,49 @@
+/***************************************************************************
+    qgsmaptoolidentifyfeature.cpp
+     --------------------------------------
+    Date                 : 22.5.2014
+    Copyright            : (C) 2014 Denis Rouzaud
+    Email                : denis.rouzaud@gmail.com
+ ***************************************************************************
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#include <QMouseEvent>
+
+#include "qgsmaptoolidentifyfeature.h"
+#include "qgsmapcanvas.h"
+
+QgsMapToolIdentifyFeature::QgsMapToolIdentifyFeature( QgsVectorLayer* vl, QgsMapCanvas* canvas )
+    : QgsMapToolIdentify( canvas )
+    , mLayer( vl )
+    , mCanvas( canvas )
+{
+}
+
+void QgsMapToolIdentifyFeature::canvasReleaseEvent( QMouseEvent* e )
+{
+
+  QgsPoint point = mCanvas->getCoordinateTransform()->toMapCoordinates( e->x(), e->y() );
+
+  QList<IdentifyResult> results;
+  if ( !identifyVectorLayer( &results, mLayer, point ) )
+    return;
+
+  // TODO: display a menu when several features identified
+
+  emit featureIdentified( results[0].mFeature );
+  emit featureIdentified( results[0].mFeature.id() );
+}
+
+void QgsMapToolIdentifyFeature::keyPressEvent( QKeyEvent* e )
+{
+  if ( e->key() == Qt::Key_Escape )
+  {
+    deactivate();
+  }
+}

src/gui/qgsmaptoolidentifyfeature.h

@@ -0,0 +1,47 @@
+/***************************************************************************
+    qgsmaptoolidentifyfeature.h
+     --------------------------------------
+    Date                 : 22.5.2014
+    Copyright            : (C) 2014 Denis Rouzaud
+    Email                : denis.rouzaud@gmail.com
+ ***************************************************************************
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#ifndef QGSMAPTOOLIDENTIFYFEATURE_H
+#define QGSMAPTOOLIDENTIFYFEATURE_H
+
+#include "qgsmaptoolidentify.h"
+
+/**
+ * @brief The QgsMapToolIdentifyFeature class is a map tool to be used to identify a feature on a chosen layer.
+ * Once the map tool is enable, user can click on the map canvas to identify a feature.
+ * A signal will then be emitted.
+ */
+class GUI_EXPORT QgsMapToolIdentifyFeature : public QgsMapToolIdentify
+{
+    Q_OBJECT
+
+  public:
+    QgsMapToolIdentifyFeature( QgsVectorLayer* vl, QgsMapCanvas* canvas );
+
+    virtual void canvasReleaseEvent( QMouseEvent* e );
+
+  signals:
+    void featureIdentified( const QgsFeature& );
+    void featureIdentified( QgsFeatureId );
+
+  protected:
+    virtual void keyPressEvent( QKeyEvent* e );
+
+  private:
+    QgsVectorLayer* mLayer;
+    QgsMapCanvas* mCanvas;
+};
+
+#endif // QGSMAPTOOLIDENTIFYFEATURE_H