don't apply loaded style when layer properties dialog is cancelled

(cherry picked from commit 25a162c)

Author: alexbruy

src/app/qgsrasterlayerproperties.cpp

@@ -30,7 +30,6 @@
 #include "qgsmapcanvas.h"
 #include "qgsmaplayerregistry.h"
 #include "qgsmaplayerstyleguiutils.h"
-#include "qgsmaplayerstylemanager.h"
 #include "qgsmaprenderer.h"
 #include "qgsmaptoolemitpoint.h"
 #include "qgsmaptopixel.h"
@@ -106,6 +105,8 @@ QgsRasterLayerProperties::QgsRasterLayerProperties( QgsMapLayer* lyr, QgsMapCanv
   connect( lyr->styleManager(), SIGNAL( currentStyleChanged( QString ) ), this, SLOT( syncToLayer() ) );
 
   connect( this, SIGNAL( accepted() ), this, SLOT( apply() ) );
+  connect( this, SIGNAL( rejected() ), this, SLOT( onCancel() ) );
+
   connect( buttonBox->button( QDialogButtonBox::Apply ), SIGNAL( clicked() ), this, SLOT( apply() ) );
 
   connect( mOptionsStackedWidget, SIGNAL( currentChanged( int ) ), this, SLOT( mOptionsStackedWidget_CurrentChanged( int ) ) );
@@ -1707,6 +1708,8 @@ void QgsRasterLayerProperties::loadStyle_clicked()
   if ( !fileName.endsWith( ".qml", Qt::CaseInsensitive ) )
     fileName += ".qml";
 
+  mOldStyle = mRasterLayer->styleManager()->style( mRasterLayer->styleManager()->currentStyle() );
+
   bool defaultLoadedFlag = false;
   QString message = mRasterLayer->loadNamedStyle( fileName, defaultLoadedFlag );
   if ( defaultLoadedFlag )
@@ -1776,4 +1779,16 @@ bool QgsRasterLayerProperties::rasterIsMultiBandColor()
   return mRasterLayer && nullptr != dynamic_cast<QgsMultiBandColorRenderer*>( mRasterLayer->renderer() );
 }
 
-
+void QgsRasterLayerProperties::onCancel()
+{
+  if ( mOldStyle.xmlData() != mRasterLayer->styleManager()->style( mRasterLayer->styleManager()->currentStyle() ).xmlData() )
+  {
+    // need to reset style to previous - style applied directly to the layer (not in apply())
+    QString myMessage;
+    QDomDocument doc( "qgis" );
+    int errorLine, errorColumn;
+    doc.setContent( mOldStyle.xmlData(), false, &myMessage, &errorLine, &errorColumn );
+    mRasterLayer->importNamedStyle( doc, myMessage );
+    syncToLayer();
+  }
+}

src/app/qgsrasterlayerproperties.h

@@ -25,6 +25,7 @@
 #include "qgsmaptool.h"
 #include "qgscolorrampshader.h"
 #include "qgscontexthelp.h"
+#include "qgsmaplayerstylemanager.h"
 
 class QgsMapLayer;
 class QgsMapCanvas;
@@ -57,6 +58,8 @@ class APP_EXPORT QgsRasterLayerProperties : public QgsOptionsDialogBase, private
     //TODO: Verify that these all need to be public
     /** \brief Applies the settings made in the dialog without closing the box */
     void apply();
+    /** Called when cancel button is pressed */
+    void onCancel();
     /** \brief Slot to update layer display name as original is edited. */
     void on_mLayerOrigNameLineEd_textEdited( const QString& text );
     /** \brief this slot asks the rasterlayer to construct pyramids */
@@ -186,5 +189,9 @@ class APP_EXPORT QgsRasterLayerProperties : public QgsOptionsDialogBase, private
     QgsRasterHistogramWidget* mHistogramWidget;
 
     QVector<bool> mTransparencyToEdited;
+
+    /** Previous layer style. Used to reset style to previous state if new style
+     * was loaded but dialog is cancelled */
+    QgsMapLayerStyle mOldStyle;
 };
 #endif

src/app/qgsvectorlayerproperties.cpp

@@ -37,7 +37,6 @@
 #include "qgslogger.h"
 #include "qgsmaplayerregistry.h"
 #include "qgsmaplayerstyleguiutils.h"
-#include "qgsmaplayerstylemanager.h"
 #include "qgspluginmetadata.h"
 #include "qgspluginregistry.h"
 #include "qgsproject.h"
@@ -660,6 +659,17 @@ void QgsVectorLayerProperties::onCancel()
 
     layer->setSubsetString( mOriginalSubsetSQL );
   }
+
+  if ( mOldStyle.xmlData() != mLayer->styleManager()->style( mLayer->styleManager()->currentStyle() ).xmlData() )
+  {
+    // need to reset style to previous - style applied directly to the layer (not in apply())
+    QString myMessage;
+    QDomDocument doc( "qgis" );
+    int errorLine, errorColumn;
+    doc.setContent( mOldStyle.xmlData(), false, &myMessage, &errorLine, &errorColumn );
+    mLayer->importNamedStyle( doc, myMessage );
+    syncToLayer();
+  }
 }
 
 void QgsVectorLayerProperties::on_pbnQueryBuilder_clicked()
@@ -826,6 +836,8 @@ void QgsVectorLayerProperties::loadStyle_clicked()
     return;
   }
 
+  mOldStyle = mLayer->styleManager()->style( mLayer->styleManager()->currentStyle() );
+
   QString myMessage;
   bool defaultLoadedFlag = false;
 

src/app/qgsvectorlayerproperties.h

@@ -30,6 +30,7 @@
 #include "qgsmapcanvas.h"
 #include "qgscontexthelp.h"
 #include "qgsexpressionbuilderdialog.h"
+#include "qgsmaplayerstylemanager.h"
 
 class QgsMapLayer;
 
@@ -187,6 +188,10 @@ class APP_EXPORT QgsVectorLayerProperties : public QgsOptionsDialogBase, private
     //! List of joins of a layer at the time of creation of the dialog. Used to return joins to previous state if dialog is cancelled
     QList< QgsVectorJoinInfo > mOldJoins;
 
+    /** Previous layer style. Used to reset style to previous state if new style
+     * was loaded but dialog is cancelled */
+    QgsMapLayerStyle mOldStyle;
+
     void initDiagramTab();
 
     /** Buffer pixmap which takes the picture of renderers before they are assigned to the vector layer*/