Better feedback and responsiveness when saving large shapefile layers

nyalldawson · nyalldawson · commit 7d2d6e89ba44 · 2017-02-16T12:32:55.000+10:00
diff --git a/src/core/qgsvectorfilewriter.cpp b/src/core/qgsvectorfilewriter.cpp
@@ -2284,6 +2284,9 @@ QgsVectorFileWriter::writeAsVectorFormat( QgsVectorLayer* layer,
     }
   }
 
+  int lastProgressReport = 0;
+  long total = options.onlySelectedFeatures ? layer->selectedFeatureCount() : layer->featureCount();
+
   if ( layer->providerType() == QLatin1String( "ogr" ) && layer->dataProvider() )
   {
     QStringList theURIParts = layer->dataProvider()->dataSourceUri().split( '|' );
@@ -2307,14 +2310,30 @@ QgsVectorFileWriter::writeAsVectorFormat( QgsVectorLayer* layer,
       req.setSubsetOfAttributes( QgsAttributeList() );
       QgsFeatureIterator fit = layer->getFeatures( req );
       QgsFeature fet;
-
+      long scanned = 0;
       while ( fit.nextFeature( fet ) )
       {
+        if ( options.feedback && options.feedback->isCanceled() )
+        {
+          return Canceled;
+        }
+        if ( options.feedback )
+        {
+          //dedicate first 5% of progress bar to this scan
+          int newProgress = ( 5.0 * scanned ) / total;
+          if ( newProgress != lastProgressReport )
+          {
+            lastProgressReport = newProgress;
+            options.feedback->setProgress( lastProgressReport );
+          }
+        }
+
         if ( fet.hasGeometry() && QgsWkbTypes::isMultiType( fet.geometry().geometry()->wkbType() ) )
         {
           destWkbType = QgsWkbTypes::multiType( destWkbType );
           break;
         }
+        scanned++;
       }
     }
   }
@@ -2426,8 +2445,7 @@ QgsVectorFileWriter::writeAsVectorFormat( QgsVectorLayer* layer,
 
   // write all features
   long saved = 0;
-  long total = options.onlySelectedFeatures ? layer->selectedFeatureCount() : layer->featureCount();
-  int lastProgressReport = 0;
+  int initialProgress = lastProgressReport;
   while ( fit.nextFeature( fet ) )
   {
     if ( options.feedback && options.feedback->isCanceled() )
@@ -2440,7 +2458,7 @@ QgsVectorFileWriter::writeAsVectorFormat( QgsVectorLayer* layer,
     if ( options.feedback )
     {
       //avoid spamming progress reports
-      int newProgress = ( 100.0 * saved ) / total;
+      int newProgress = initialProgress + (( 100.0 - initialProgress ) * saved ) / total;
       if ( newProgress < 100 && newProgress != lastProgressReport )
       {
         lastProgressReport = newProgress;

Original file line number	Diff line number	Diff line change
`@@ -2284,6 +2284,9 @@ QgsVectorFileWriter::writeAsVectorFormat( QgsVectorLayer* layer,`
`2284`	`2284`	`}`
`2285`	`2285`	`}`
`2286`	`2286`
	`2287`	`+ int lastProgressReport = 0;`
	`2288`	`+ long total = options.onlySelectedFeatures ? layer->selectedFeatureCount() : layer->featureCount();`
	`2289`	`+`
`2287`	`2290`	`if ( layer->providerType() == QLatin1String( "ogr" ) && layer->dataProvider() )`
`2288`	`2291`	`{`
`2289`	`2292`	`QStringList theURIParts = layer->dataProvider()->dataSourceUri().split( '\|' );`
`@@ -2307,14 +2310,30 @@ QgsVectorFileWriter::writeAsVectorFormat( QgsVectorLayer* layer,`
`2307`	`2310`	`req.setSubsetOfAttributes( QgsAttributeList() );`
`2308`	`2311`	`QgsFeatureIterator fit = layer->getFeatures( req );`
`2309`	`2312`	`QgsFeature fet;`
`2310`		`-`
	`2313`	`+ long scanned = 0;`
`2311`	`2314`	`while ( fit.nextFeature( fet ) )`
`2312`	`2315`	`{`
	`2316`	`+ if ( options.feedback && options.feedback->isCanceled() )`
	`2317`	`+ {`
	`2318`	`+ return Canceled;`
	`2319`	`+ }`
	`2320`	`+ if ( options.feedback )`
	`2321`	`+ {`
	`2322`	`+ //dedicate first 5% of progress bar to this scan`
	`2323`	`+ int newProgress = ( 5.0 * scanned ) / total;`
	`2324`	`+ if ( newProgress != lastProgressReport )`
	`2325`	`+ {`
	`2326`	`+ lastProgressReport = newProgress;`
	`2327`	`+ options.feedback->setProgress( lastProgressReport );`
	`2328`	`+ }`
	`2329`	`+ }`
	`2330`	`+`
`2313`	`2331`	`if ( fet.hasGeometry() && QgsWkbTypes::isMultiType( fet.geometry().geometry()->wkbType() ) )`
`2314`	`2332`	`{`
`2315`	`2333`	`destWkbType = QgsWkbTypes::multiType( destWkbType );`
`2316`	`2334`	`break;`
`2317`	`2335`	`}`
	`2336`	`+ scanned++;`
`2318`	`2337`	`}`
`2319`	`2338`	`}`
`2320`	`2339`	`}`
`@@ -2426,8 +2445,7 @@ QgsVectorFileWriter::writeAsVectorFormat( QgsVectorLayer* layer,`
`2426`	`2445`
`2427`	`2446`	`// write all features`
`2428`	`2447`	`long saved = 0;`
`2429`		`- long total = options.onlySelectedFeatures ? layer->selectedFeatureCount() : layer->featureCount();`
`2430`		`- int lastProgressReport = 0;`
	`2448`	`+ int initialProgress = lastProgressReport;`
`2431`	`2449`	`while ( fit.nextFeature( fet ) )`
`2432`	`2450`	`{`
`2433`	`2451`	`if ( options.feedback && options.feedback->isCanceled() )`
`@@ -2440,7 +2458,7 @@ QgsVectorFileWriter::writeAsVectorFormat( QgsVectorLayer* layer,`
`2440`	`2458`	`if ( options.feedback )`
`2441`	`2459`	`{`
`2442`	`2460`	`//avoid spamming progress reports`
`2443`		`- int newProgress = ( 100.0 * saved ) / total;`
	`2461`	`+ int newProgress = initialProgress + (( 100.0 - initialProgress ) * saved ) / total;`
`2444`	`2462`	`if ( newProgress < 100 && newProgress != lastProgressReport )`
`2445`	`2463`	`{`
`2446`	`2464`	`lastProgressReport = newProgress;`