Remove QgsInterruptionChecker and replace with QgsFeedback use

There's little need for two classes with similar goals here.

Author: nyalldawson

doc/api_break.dox

@@ -287,6 +287,7 @@ should now call QgsCoordinateReferenceSystem::invalidateCache() and QgsCoordinat
 - HalfEdge.
 - QgsHtmlAnnotationItem. Use QgsHtmlAnnotation instead.
 - QgsHttpTransaction. This class was outdated and code should be ported to native Qt or Python implementations.
+- QgsInterruptionChecker. Use QgsFeedback instead.
 - QgsGenericProjectionSelector. Use QgsProjectionSelectionTreeWidget instead.
 - QgsGeometryCache. It got redundant after removal of old snapping classes (QgsSnapper + friends).
 - QgsLabel and QgsLabelAttributes. Replaced by labeling based on PAL library, see QgsLabelingEngine.
@@ -1031,6 +1032,13 @@ None will need to be modified, as the method will return an empty geometry if th
 - fields() no longer returns a pointer, but instead a QgsFields value.
 - The duplicate method setFeatureId() was removed. Use setId() instead.
 
+
+QgsFeatureIterator        {#qgis_api_break_3_0_QgsFeatureIterator}
+------------------
+
+- setInterruptionChecker now accepts a QgsFeedback object instead of a QgsInterruptionChecker.
+
+
 QgsFeatureListViewDelegate        {#qgis_api_break_3_0_QgsFeatureListViewDelegate}
 --------------------------
 

python/core/qgsfeatureiterator.sip.in

@@ -8,8 +8,6 @@
 
 
 
-
-
 class QgsAbstractFeatureIterator
 {
 %Docstring

src/core/CMakeLists.txt

@@ -637,6 +637,7 @@ SET(QGIS_CORE_MOC_HDRS
   qgsvectorlayerexporter.h
   qgsvectorlayerfeaturecounter.h
   qgsvectorlayerjoinbuffer.h
+  qgsvectorlayerrenderer.h
   qgsvectorlayertools.h
   qgsmapthemecollection.h
   qgswebpage.h
@@ -920,7 +921,6 @@ SET(QGIS_CORE_HDRS
   qgsvectorlayerjoininfo.h
   qgsvectorlayerlabelprovider.h
   qgsvectorlayerlabeling.h
-  qgsvectorlayerrenderer.h
   qgsvectorlayerundocommand.h
   qgsvectorlayerundopassthroughcommand.h
   qgsvectorlayerutils.h

src/core/qgsfeatureiterator.cpp

@@ -211,7 +211,7 @@ bool QgsAbstractFeatureIterator::prepareOrderBy( const QList<QgsFeatureRequest::
   return false;
 }
 
-void QgsAbstractFeatureIterator::setInterruptionChecker( QgsInterruptionChecker * )
+void QgsAbstractFeatureIterator::setInterruptionChecker( QgsFeedback * )
 {
 }
 

src/core/qgsfeatureiterator.h

@@ -19,21 +19,7 @@
 #include "qgsfeaturerequest.h"
 #include "qgsindexedfeature.h"
 
-
-
-/**
- * \ingroup core
- * Interface that can be optionally attached to an iterator so its
- * nextFeature() implementaton can check if it must stop as soon as possible.
- * \since QGIS 2.16
- * \note not available in Python bindings
- */
-class CORE_EXPORT QgsInterruptionChecker SIP_SKIP
-{
-  public:
-    //! return true if the iterator must stop as soon as possible
-    virtual bool mustStop() const = 0;
-};
+class QgsFeedback;
 
 /**
  * \ingroup core
@@ -74,7 +60,7 @@ class CORE_EXPORT QgsAbstractFeatureIterator
      * \since QGIS 2.16
      * \note not available in Python bindings
      */
-    virtual void setInterruptionChecker( QgsInterruptionChecker *interruptionChecker ) SIP_SKIP;
+    virtual void setInterruptionChecker( QgsFeedback *interruptionChecker ) SIP_SKIP;
 
     /**
      * Returns the status of expression compilation for filter expression requests.
@@ -329,7 +315,7 @@ class CORE_EXPORT QgsFeatureIterator
      * \since QGIS 2.16
      * \note not available in Python bindings
      */
-    void setInterruptionChecker( QgsInterruptionChecker *interruptionChecker ) SIP_SKIP;
+    void setInterruptionChecker( QgsFeedback *interruptionChecker ) SIP_SKIP;
 
     /**
      * Returns the status of expression compilation for filter expression requests.
@@ -404,7 +390,7 @@ inline bool operator!= ( const QgsFeatureIterator &fi1, const QgsFeatureIterator
   return !( fi1 == fi2 );
 }
 
-inline void QgsFeatureIterator::setInterruptionChecker( QgsInterruptionChecker *interruptionChecker )
+inline void QgsFeatureIterator::setInterruptionChecker( QgsFeedback *interruptionChecker )
 {
   if ( mIter )
     mIter->setInterruptionChecker( interruptionChecker );

src/core/qgsvectorlayerfeatureiterator.cpp

@@ -402,7 +402,7 @@ bool QgsVectorLayerFeatureIterator::close()
   return true;
 }
 
-void QgsVectorLayerFeatureIterator::setInterruptionChecker( QgsInterruptionChecker *interruptionChecker )
+void QgsVectorLayerFeatureIterator::setInterruptionChecker( QgsFeedback *interruptionChecker )
 {
   mProviderIterator.setInterruptionChecker( interruptionChecker );
   mInterruptionChecker = interruptionChecker;

src/core/qgsvectorlayerfeatureiterator.h

@@ -119,7 +119,7 @@ class CORE_EXPORT QgsVectorLayerFeatureIterator : public QgsAbstractFeatureItera
     //! end of iterating: free the resources / lock
     bool close() override;
 
-    void setInterruptionChecker( QgsInterruptionChecker *interruptionChecker ) override SIP_SKIP;
+    void setInterruptionChecker( QgsFeedback *interruptionChecker ) override SIP_SKIP;
 
     /**
      * Join information prepared for fast attribute id mapping in QgsVectorLayerJoinBuffer::updateFeatureAttributes().
@@ -247,7 +247,7 @@ class CORE_EXPORT QgsVectorLayerFeatureIterator : public QgsAbstractFeatureItera
 
     std::unique_ptr<QgsExpressionContext> mExpressionContext;
 
-    QgsInterruptionChecker *mInterruptionChecker = nullptr;
+    QgsFeedback *mInterruptionChecker = nullptr;
 
     QList< int > mPreparedFields;
     QList< int > mFieldsToPrepare;

src/core/qgsvectorlayerrenderer.cpp

@@ -549,10 +549,16 @@ void QgsVectorLayerRenderer::prepareDiagrams( QgsVectorLayer *layer, QSet<QStrin
 QgsVectorLayerRendererInterruptionChecker::QgsVectorLayerRendererInterruptionChecker
 ( const QgsRenderContext &context )
   : mContext( context )
+  , mTimer( new QTimer( this ) )
 {
-}
+  connect( mTimer, &QTimer::timeout, this, [ = ]
+  {
+    if ( mContext.renderingStopped() )
+    {
+      mTimer->stop();
+      cancel();
+    }
+  } );
+  mTimer->start( 50 );
 
-bool QgsVectorLayerRendererInterruptionChecker::mustStop() const
-{
-  return mContext.renderingStopped();
 }

src/core/qgsvectorlayerrenderer.h

@@ -39,6 +39,7 @@ typedef QList<int> QgsAttributeList;
 #include "qgsfeature.h"  // QgsFeatureIds
 #include "qgsfeatureiterator.h"
 #include "qgsvectorsimplifymethod.h"
+#include "qgsfeedback.h"
 
 #include "qgsmaplayerrenderer.h"
 
@@ -50,14 +51,17 @@ class QgsVectorLayerDiagramProvider;
  * Interruption checker used by QgsVectorLayerRenderer::render()
  * \note not available in Python bindings
  */
-class QgsVectorLayerRendererInterruptionChecker: public QgsInterruptionChecker
+class QgsVectorLayerRendererInterruptionChecker: public QgsFeedback
 {
+    Q_OBJECT
+
   public:
     //! Constructor
     explicit QgsVectorLayerRendererInterruptionChecker( const QgsRenderContext &context );
-    bool mustStop() const override;
+
   private:
     const QgsRenderContext &mContext;
+    QTimer *mTimer = nullptr;
 };
 
 /**

src/providers/wfs/qgswfsfeatureiterator.cpp

@@ -27,6 +27,7 @@
 #include "qgslogger.h"
 #include "qgssettings.h"
 #include "qgsexception.h"
+#include "qgsfeedback.h"
 
 #include <QDir>
 #include <QProgressDialog>
@@ -965,7 +966,7 @@ void QgsWFSFeatureIterator::endOfDownload( bool )
     mLoop->quit();
 }
 
-void QgsWFSFeatureIterator::setInterruptionChecker( QgsInterruptionChecker *interruptionChecker )
+void QgsWFSFeatureIterator::setInterruptionChecker( QgsFeedback *interruptionChecker )
 {
   mInterruptionChecker = interruptionChecker;
 }
@@ -1018,7 +1019,7 @@ void QgsWFSFeatureIterator::checkInterruption()
 {
   //QgsDebugMsg("QgsWFSFeatureIterator::checkInterruption()");
 
-  if ( mInterruptionChecker && mInterruptionChecker->mustStop() )
+  if ( mInterruptionChecker && mInterruptionChecker->isCanceled() )
   {
     mDownloadFinished = true;
     if ( mLoop )
@@ -1037,7 +1038,7 @@ bool QgsWFSFeatureIterator::fetchFeature( QgsFeature &f )
   QgsFeature cachedFeature;
   while ( mCacheIterator.nextFeature( cachedFeature ) )
   {
-    if ( mInterruptionChecker && mInterruptionChecker->mustStop() )
+    if ( mInterruptionChecker && mInterruptionChecker->isCanceled() )
       return false;
 
     //QgsDebugMsg(QString("QgsWFSSharedData::fetchFeature() : mCacheIterator.nextFeature(cachedFeature)") );
@@ -1134,7 +1135,7 @@ bool QgsWFSFeatureIterator::fetchFeature( QgsFeature &f )
     {
       while ( !mReaderStream->atEnd() )
       {
-        if ( mInterruptionChecker && mInterruptionChecker->mustStop() )
+        if ( mInterruptionChecker && mInterruptionChecker->isCanceled() )
           return false;
 
         QgsFeature feat;
@@ -1186,7 +1187,7 @@ bool QgsWFSFeatureIterator::fetchFeature( QgsFeature &f )
 
     if ( mDownloadFinished )
       return false;
-    if ( mInterruptionChecker && mInterruptionChecker->mustStop() )
+    if ( mInterruptionChecker && mInterruptionChecker->isCanceled() )
       return false;
 
     //QgsDebugMsg("fetchFeature before loop");

src/providers/wfs/qgswfsfeatureiterator.h

@@ -206,7 +206,7 @@ class QgsWFSFeatureIterator : public QObject,
 
     bool close() override;
 
-    void setInterruptionChecker( QgsInterruptionChecker *interruptionChecker ) override;
+    void setInterruptionChecker( QgsFeedback *interruptionChecker ) override;
 
     //! Used by QgsWFSSharedData::registerToCache()
     void connectSignals( QgsWFSFeatureDownloader *downloader );
@@ -232,7 +232,7 @@ class QgsWFSFeatureIterator : public QObject,
     bool mDownloadFinished;
     QEventLoop *mLoop = nullptr;
     QgsFeatureIterator mCacheIterator;
-    QgsInterruptionChecker *mInterruptionChecker = nullptr;
+    QgsFeedback *mInterruptionChecker = nullptr;
 
     //! this mutex synchronizes the mWriterXXXX variables between featureReceivedSynchronous() and fetchFeature()
     QMutex mMutex;