Fix opacity slider crash

Fixes a race condition introduced by the timer.
qgis · Jul 21, 2021 · 15d4196 · 15d4196
1 parent 96f2cdb
commit 15d4196
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Showing 2 changed files with 6 additions and 1 deletion.
diff --git a/src/gui/layertree/qgslayertreeembeddedwidgetsimpl.cpp b/src/gui/layertree/qgslayertreeembeddedwidgetsimpl.cpp
@@ -71,13 +71,17 @@ void QgsLayerTreeOpacityWidget::sliderValueChanged( int value )
 
 void QgsLayerTreeOpacityWidget::updateOpacityFromSlider()
 {
+  if ( !mLayer )
+    return;
   int value = mSlider->value();
   mLayer->setOpacity( value / 1000.0 );
   mLayer->triggerRepaint();
 }
 
 void QgsLayerTreeOpacityWidget::layerTrChanged()
 {
+  if ( !mLayer )
+    return;
   mSlider->blockSignals( true );
   mSlider->setValue( mLayer->opacity() * 1000.0 );
   mSlider->blockSignals( false );

diff --git a/src/gui/layertree/qgslayertreeembeddedwidgetsimpl.h b/src/gui/layertree/qgslayertreeembeddedwidgetsimpl.h
@@ -16,6 +16,7 @@
 #ifndef QGSLAYERTREEEMBEDDEDWIDGETSIMPL_H
 #define QGSLAYERTREEEMBEDDEDWIDGETSIMPL_H
 
+#include <QPointer>
 #include <QWidget>
 #include "qgslayertreeembeddedwidgetregistry.h"
 
@@ -56,7 +57,7 @@ class QgsLayerTreeOpacityWidget : public QWidget
     void layerTrChanged();
 
   private:
-    QgsMapLayer *mLayer = nullptr;
+    QPointer<QgsMapLayer> mLayer;
     QSlider *mSlider = nullptr;
     QTimer *mTimer = nullptr;
 };