add select all features methods for vector layers

Author: 3nids

python/core/qgsvectorlayer.sip

@@ -239,6 +239,9 @@ class QgsVectorLayer : QgsMapLayer
 
     /** Select not selected features and deselect selected ones */
     void invertSelection();
+    
+    /** Select all the features */
+    void selectAll();
 
     /** Invert selection of features found within the search rectangle (in layer's coordinates) */
     void invertSelectionInRectangle( QgsRectangle & rect );

src/core/qgsvectorlayer.cpp

@@ -812,6 +812,23 @@ void QgsVectorLayer::invertSelection()
   setSelectedFeatures( ids );
 }
 
+void QgsVectorLayer::selectAll()
+{
+    QgsFeatureIterator fit = getFeatures( QgsFeatureRequest()
+                                          .setFlags( QgsFeatureRequest::NoGeometry )
+                                          .setSubsetOfAttributes( QgsAttributeList() ) );
+
+    QgsFeatureIds ids;
+
+    QgsFeature fet;
+    while ( fit.nextFeature( fet ) )
+    {
+      ids << fet.id();
+    }
+
+    setSelectedFeatures( ids );
+}
+
 void QgsVectorLayer::invertSelectionInRectangle( QgsRectangle & rect )
 {
   // normalize the rectangle

src/core/qgsvectorlayer.h

@@ -619,6 +619,9 @@ class CORE_EXPORT QgsVectorLayer : public QgsMapLayer
     /** Select not selected features and deselect selected ones */
     void invertSelection();
 
+    /** Select all the features */
+    void selectAll();
+
     /**
      * Invert selection of features found within the search rectangle (in layer's coordinates)
      *