Various safety checks to avoid crashes

Fix #35940
qgis · Apr 23, 2020 · 6a27a82 · 6a27a82
1 parent f13a200
commit 6a27a82
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Showing 5 changed files with 46 additions and 33 deletions.
diff --git a/src/gui/symbology/qgscategorizedsymbolrendererwidget.cpp b/src/gui/symbology/qgscategorizedsymbolrendererwidget.cpp
@@ -575,7 +575,7 @@ QgsCategorizedSymbolRendererWidget::QgsCategorizedSymbolRendererWidget( QgsVecto
   advMenu->addAction( tr( "Match to Saved Symbols" ), this, SLOT( matchToSymbolsFromLibrary() ) );
   advMenu->addAction( tr( "Match to Symbols from File…" ), this, SLOT( matchToSymbolsFromXml() ) );
   advMenu->addAction( tr( "Symbol Levels…" ), this, SLOT( showSymbolLevels() ) );
-  if ( mCategorizedSymbol->type() == QgsSymbol::Marker )
+  if ( mCategorizedSymbol && mCategorizedSymbol->type() == QgsSymbol::Marker )
   {
     QAction *actionDdsLegend = advMenu->addAction( tr( "Data-defined Size Legend…" ) );
     // only from Qt 5.6 there is convenience addAction() with new style connection

diff --git a/src/gui/symbology/qgsgraduatedsymbolrendererwidget.cpp b/src/gui/symbology/qgsgraduatedsymbolrendererwidget.cpp
@@ -507,38 +507,41 @@ QgsGraduatedSymbolRendererWidget::QgsGraduatedSymbolRendererWidget( QgsVectorLay
   viewGraduated->setStyle( new QgsGraduatedSymbolRendererViewStyle( viewGraduated ) );
 
   mGraduatedSymbol.reset( QgsSymbol::defaultSymbol( mLayer->geometryType() ) );
-  btnChangeGraduatedSymbol->setSymbolType( mGraduatedSymbol->type() );
-  btnChangeGraduatedSymbol->setSymbol( mGraduatedSymbol->clone() );
-
-  methodComboBox->blockSignals( true );
-  methodComboBox->addItem( tr( "Color" ), ColorMode );
-  switch ( mGraduatedSymbol->type() )
+  if ( mGraduatedSymbol )
   {
-    case QgsSymbol::Marker:
-    {
-      methodComboBox->addItem( tr( "Size" ), SizeMode );
-      minSizeSpinBox->setValue( 1 );
-      maxSizeSpinBox->setValue( 8 );
-      break;
-    }
-    case QgsSymbol::Line:
-    {
-      methodComboBox->addItem( tr( "Size" ), SizeMode );
-      minSizeSpinBox->setValue( .1 );
-      maxSizeSpinBox->setValue( 2 );
-      break;
-    }
-    case QgsSymbol::Fill:
+    btnChangeGraduatedSymbol->setSymbolType( mGraduatedSymbol->type() );
+    btnChangeGraduatedSymbol->setSymbol( mGraduatedSymbol->clone() );
+
+    methodComboBox->blockSignals( true );
+    methodComboBox->addItem( tr( "Color" ), ColorMode );
+    switch ( mGraduatedSymbol->type() )
     {
-      //set button and label invisible to avoid display of a single item combobox
-      methodComboBox->hide();
-      labelMethod->hide();
-      break;
+      case QgsSymbol::Marker:
+      {
+        methodComboBox->addItem( tr( "Size" ), SizeMode );
+        minSizeSpinBox->setValue( 1 );
+        maxSizeSpinBox->setValue( 8 );
+        break;
+      }
+      case QgsSymbol::Line:
+      {
+        methodComboBox->addItem( tr( "Size" ), SizeMode );
+        minSizeSpinBox->setValue( .1 );
+        maxSizeSpinBox->setValue( 2 );
+        break;
+      }
+      case QgsSymbol::Fill:
+      {
+        //set button and label invisible to avoid display of a single item combobox
+        methodComboBox->hide();
+        labelMethod->hide();
+        break;
+      }
+      case QgsSymbol::Hybrid:
+        break;
     }
-    case QgsSymbol::Hybrid:
-      break;
+    methodComboBox->blockSignals( false );
   }
-  methodComboBox->blockSignals( false );
 
   connect( mExpressionWidget, static_cast < void ( QgsFieldExpressionWidget::* )( const QString & ) >( &QgsFieldExpressionWidget::fieldChanged ), this, &QgsGraduatedSymbolRendererWidget::graduatedColumnChanged );
   connect( viewGraduated, &QAbstractItemView::doubleClicked, this, &QgsGraduatedSymbolRendererWidget::rangesDoubleClicked );
@@ -565,7 +568,7 @@ QgsGraduatedSymbolRendererWidget::QgsGraduatedSymbolRendererWidget( QgsVectorLay
   QMenu *advMenu = new QMenu( this );
 
   advMenu->addAction( tr( "Symbol Levels…" ), this, SLOT( showSymbolLevels() ) );
-  if ( mGraduatedSymbol->type() == QgsSymbol::Marker )
+  if ( mGraduatedSymbol && mGraduatedSymbol->type() == QgsSymbol::Marker )
   {
     QAction *actionDdsLegend = advMenu->addAction( tr( "Data-defined Size Legend…" ) );
     // only from Qt 5.6 there is convenience addAction() with new style connection

diff --git a/src/gui/symbology/qgsheatmaprendererwidget.cpp b/src/gui/symbology/qgsheatmaprendererwidget.cpp
@@ -80,6 +80,8 @@ QgsHeatmapRendererWidget::QgsHeatmapRendererWidget( QgsVectorLayer *layer, QgsSt
     QLabel *label = new QLabel( tr( "The heatmap renderer only applies to point and multipoint layers. \n"
                                     "'%1' is not a point layer and cannot be rendered as a heatmap." )
                                 .arg( layer->name() ), this );
+    if ( !layout() )
+      setLayout( new QGridLayout() );
     layout()->addWidget( label );
     return;
   }

diff --git a/src/gui/symbology/qgssinglesymbolrendererwidget.cpp b/src/gui/symbology/qgssinglesymbolrendererwidget.cpp
@@ -47,11 +47,13 @@ QgsSingleSymbolRendererWidget::QgsSingleSymbolRendererWidget( QgsVectorLayer *la
   {
     QgsSymbol *symbol = QgsSymbol::defaultSymbol( mLayer->geometryType() );
 
-    mRenderer = new QgsSingleSymbolRenderer( symbol );
+    if ( symbol )
+      mRenderer = new QgsSingleSymbolRenderer( symbol );
   }
 
   // load symbol from it
-  mSingleSymbol = mRenderer->symbol()->clone();
+  if ( mRenderer )
+    mSingleSymbol = mRenderer->symbol()->clone();
 
   // setup ui
   mSelector = new QgsSymbolSelectorWidget( mSingleSymbol, mStyle, mLayer, nullptr );
@@ -73,7 +75,7 @@ QgsSingleSymbolRendererWidget::QgsSingleSymbolRendererWidget( QgsVectorLayer *la
 
   QAction *actionLevels = advMenu->addAction( tr( "Symbol Levels…" ) );
   connect( actionLevels, &QAction::triggered, this, &QgsSingleSymbolRendererWidget::showSymbolLevels );
-  if ( mSingleSymbol->type() == QgsSymbol::Marker )
+  if ( mSingleSymbol && mSingleSymbol->type() == QgsSymbol::Marker )
   {
     QAction *actionDdsLegend = advMenu->addAction( tr( "Data-defined Size Legend…" ) );
     // only from Qt 5.6 there is convenience addAction() with new style connection

diff --git a/src/gui/symbology/qgssymbolselectordialog.cpp b/src/gui/symbology/qgssymbolselectordialog.cpp
@@ -385,6 +385,9 @@ QgsSymbolWidgetContext QgsSymbolSelectorWidget::context() const
 
 void QgsSymbolSelectorWidget::loadSymbol( QgsSymbol *symbol, SymbolLayerItem *parent )
 {
+  if ( !symbol )
+    return;
+
   if ( !parent )
   {
     mSymbol = symbol;
@@ -449,6 +452,9 @@ void QgsSymbolSelectorWidget::updateUi()
 
 void QgsSymbolSelectorWidget::updatePreview()
 {
+  if ( !mSymbol )
+    return;
+
   std::unique_ptr< QgsSymbol > symbolClone( mSymbol->clone() );
   QImage preview = symbolClone->bigSymbolPreviewImage( &mPreviewExpressionContext );
   lblPreview->setPixmap( QPixmap::fromImage( preview ) );