[FEATURE]: added reload method to map layers and provider interface. Like this, caching providers (currently WMS and WFS) can synchronize with changes in the datasource

git-svn-id: http://svn.osgeo.org/qgis/trunk/qgis@14264 c8812cc2-4d05-0410-92ff-de0c093fc19c

Author: mhugent

python/core/qgsdataprovider.sip

@@ -178,6 +178,10 @@ class QgsDataProvider : QObject
     */
     virtual QString fileRasterFilters() const;
 
+    /**Reloads the data from the the source. Needs to be implemented by providers with data caches to
+      synchronize with changes in the data source*/
+    virtual void reloadData();
+
   signals:
 
       /** 

python/core/qgsmaplayer.sip

@@ -70,6 +70,10 @@ public:
      */
     const QString & name() const;
 
+    /**Synchronises with changes in the datasource
+      @note added in version 1.6*/
+    virtual void reload();
+
     /** Render the layer, to be overridden in child classes
      */
     virtual bool draw(QgsRenderContext& rendererContext);

python/core/qgsmaplayerregistry.sip

@@ -67,6 +67,10 @@ public:
  */
  void clearAllLayerCaches();
 
+ /**Reload all provider data caches (currently used for WFS and WMS providers)
+ @note: this method was added in QGIS 1.6*/
+ void reloadAllLayers();
+
 signals:
 
     /** emitted when a layer is removed from the registry

python/core/qgsrasterlayer.sip

@@ -303,6 +303,10 @@ public:
     /** Returns the data provider in a const-correct manner */
     //const QgsRasterDataProvider* dataProvider() const;
 
+    /**Synchronises with changes in the datasource
+    @note added in version 1.6*/
+    virtual void reload();
+
     /** \brief This is called when the view on the raster layer needs to be redrawn */
     bool draw( QgsRenderContext& rendererContext );
 

python/core/qgsvectorlayer.sip

@@ -333,6 +333,10 @@ public:
   int snapWithContext(const QgsPoint& startPoint, double snappingTolerance, QMultiMap<double, QgsSnappingResult>& snappingResults /Out/,
                       QgsSnapper::SnappingType snap_to);
 
+  /**Synchronises with changes in the datasource
+  @note added in version 1.6*/
+  virtual void reload();
+
   /** Draws the layer using coordinate transformation
    *  @return FALSE if an error occurred during drawing
    */

src/app/qgisapp.cpp

@@ -4706,6 +4706,8 @@ void QgisApp::refreshMapCanvas()
 {
   //clear all caches first
   QgsMapLayerRegistry::instance()->clearAllLayerCaches();
+  //reload cached provider data
+  QgsMapLayerRegistry::instance()->reloadAllLayers();
   //then refresh
   mMapCanvas->refresh();
 }

src/core/qgsdataprovider.h

@@ -267,6 +267,10 @@ class CORE_EXPORT QgsDataProvider : public QObject
       return "";
     }
 
+    /**Reloads the data from the the source. Needs to be implemented by providers with data caches to
+      synchronize with changes in the data source*/
+    virtual void reloadData() {}
+
   signals:
 
     /**

src/core/qgsmaplayer.h

@@ -79,6 +79,10 @@ class CORE_EXPORT QgsMapLayer : public QObject
      */
     QString const & name() const;
 
+    /**Synchronises with changes in the datasource
+        @note added in version 1.6*/
+    virtual void reload() {}
+
     /** This is the method that does the actual work of
      * drawing the layer onto a paint device.
      * @param QgsRenderContext - describes the extents,

src/core/qgsmaplayerregistry.cpp

@@ -22,7 +22,6 @@
 #include "qgsmaplayer.h"
 #include "qgslogger.h"
 
-
 //
 // Static calls to enforce singleton behaviour
 //
@@ -128,6 +127,19 @@ void QgsMapLayerRegistry::clearAllLayerCaches()
   }
 } // QgsMapLayerRegistry::clearAllLayerCaches()
 
+void QgsMapLayerRegistry::reloadAllLayers()
+{
+  QMap<QString, QgsMapLayer *>::iterator it;
+  for ( it = mMapLayers.begin(); it != mMapLayers.end() ; ++it )
+  {
+    QgsMapLayer* layer = it.value();
+    if ( layer )
+    {
+      layer->reload();
+    }
+  }
+}
+
 QMap<QString, QgsMapLayer*> & QgsMapLayerRegistry::mapLayers()
 {
   return mMapLayers;

src/core/qgsmaplayerregistry.h

@@ -89,6 +89,11 @@ class CORE_EXPORT QgsMapLayerRegistry : public QObject
      * @note this method was added in QGIS 1.4
      */
     void clearAllLayerCaches();
+
+    /**Reload all provider data caches (currently used for WFS and WMS providers)
+      @note: this method was added in QGIS 1.6*/
+    void reloadAllLayers();
+
   signals:
 
     /** emitted when a layer is removed from the registry