QgsProjectTranslator

implementation of abstract class QgsProjectTranslator

src/core/CMakeLists.txt

@@ -636,7 +636,6 @@ SET(QGIS_CORE_MOC_HDRS
   qgstaskmanager.h
   qgstolerance.h
   qgstracer.h
-  qgstranslationcontext.h
   qgstrackedvectorlayertools.h
   qgstransaction.h
   qgstransactiongroup.h

src/core/layertree/qgslayertreegroup.cpp

@@ -268,7 +268,7 @@ QgsLayerTreeGroup *QgsLayerTreeGroup::readXml( QDomElement &element, const QgsRe
   if ( element.tagName() != QLatin1String( "layer-tree-group" ) )
     return nullptr;
 
-  QString name =  QgsProject::instance()->translate( QStringLiteral( "project:layergroups" ), element.attribute( QStringLiteral( "name" ) ) );
+  QString name =  context.projectTranslator()->translate( QStringLiteral( "project:layergroups" ), element.attribute( QStringLiteral( "name" ) ) );
   bool isExpanded = ( element.attribute( QStringLiteral( "expanded" ), QStringLiteral( "1" ) ) == QLatin1String( "1" ) );
   bool checked = QgsLayerTreeUtils::checkStateFromXml( element.attribute( QStringLiteral( "checked" ) ) ) != Qt::Unchecked;
   bool isMutuallyExclusive = element.attribute( QStringLiteral( "mutually-exclusive" ), QStringLiteral( "0" ) ) == QLatin1String( "1" );

src/core/qgsmaplayer.cpp

@@ -316,7 +316,7 @@ bool QgsMapLayer::readLayerXml( const QDomElement &layerElement,  QgsReadWriteCo
   mne = mnl.toElement();
 
   //name can be translated
-  setName( QgsProject::instance()->translate( QStringLiteral( "project:layers:%1" ).arg( layerElement.namedItem( QStringLiteral( "id" ) ).toElement().text() ), mne.text() ) );
+  setName( context.projectTranslator()->translate( QStringLiteral( "project:layers:%1" ).arg( layerElement.namedItem( QStringLiteral( "id" ) ).toElement().text() ), mne.text() ) );
 
   //short name
   QDomElement shortNameElem = layerElement.firstChildElement( QStringLiteral( "shortname" ) );

src/core/qgsproject.cpp

@@ -2819,7 +2819,7 @@ void QgsProject::generateTsFile( const QString &locale )
   translationContext.writeTsFile( locale );
 }
 
-QString QgsProject::translate( const QString &context, const QString &sourceText, const char *disambiguation, int n )
+QString QgsProject::translate( const QString &context, const QString &sourceText, const char *disambiguation, int n ) const
 {
   if ( !mTranslator )
   {

src/core/qgsproject.h

@@ -47,6 +47,7 @@
 #include "qgsprojectmetadata.h"
 #include "qgstranslationcontext.h"
 #include "qgsvectorlayer.h"
+#include "qgsprojecttranslator.h"
 
 class QFileInfo;
 class QDomDocument;
@@ -85,7 +86,7 @@ class QgsAuxiliaryStorage;
 
 */
 
-class CORE_EXPORT QgsProject : public QObject, public QgsExpressionContextGenerator
+class CORE_EXPORT QgsProject : public QObject, public QgsExpressionContextGenerator, public QgsProjectTranslator
 {
     Q_OBJECT
     Q_PROPERTY( QStringList nonIdentifiableLayers READ nonIdentifiableLayers WRITE setNonIdentifiableLayers NOTIFY nonIdentifiableLayersChanged )
@@ -980,7 +981,7 @@ class CORE_EXPORT QgsProject : public QObject, public QgsExpressionContextGenera
      * \param disambiguation it's the disambiguation
      * \param n if -1 uses the appropriate form
      */
-    QString translate( const QString &context, const QString &sourceText, const char *disambiguation = nullptr, int n = -1 );
+    QString translate( const QString &context, const QString &sourceText, const char *disambiguation = nullptr, int n = -1 ) const override;
 
   signals:
 

src/core/qgsprojecttranslator.h

@@ -0,0 +1,45 @@
+/***************************************************************************
+  qgsprojecttranslator.h
+
+ ---------------------
+ begin                : 24.7.2018
+ copyright            : (C) 2018 by david signer
+ email                : david at opengis dot ch
+ ***************************************************************************
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ ***************************************************************************/
+#ifndef QGSPROJECTTRANSLATOR_H
+#define QGSPROJECTTRANSLATOR_H
+
+#include "qgis_core.h"
+#include "qgis_sip.h"
+#include "qgis.h"
+#include <QString>
+
+/**
+ * \ingroup core
+ * This abstract class is to call translate() for project data from wherever QgsReadWriteContext is available.
+ *
+ * \since QGIS 3.4
+ */
+
+class CORE_EXPORT QgsProjectTranslator
+{
+  public:
+
+    /**
+     * This method needs to be reimplemented in all classes which implement this interface
+     *
+     * \since QGIS 3.4
+     */
+    virtual QString translate( const QString &context, const QString &sourceText, const char *disambiguation = nullptr, int n = -1 ) const = 0;
+
+    virtual ~QgsProjectTranslator() = default;
+};
+
+#endif // QGSPROJECTTRANSLATOR_H

src/core/qgsreadwritecontext.h

@@ -20,6 +20,7 @@
 
 #include "qgspathresolver.h"
 #include "qgis.h"
+#include "qgsprojecttranslator.h"
 
 class QgsReadWriteContextCategoryPopper;
 
@@ -99,6 +100,11 @@ class CORE_EXPORT QgsReadWriteContext
      */
     QList<QgsReadWriteContext::ReadWriteMessage> takeMessages();
 
+    /**
+     * Returns the project translator
+     * \since QGIS 3.2
+     */
+    const QgsProjectTranslator *projectTranslator( ) const { return mProjectTranslator; }
 
   private:
     //! Pop the last category
@@ -107,6 +113,7 @@ class CORE_EXPORT QgsReadWriteContext
     QgsPathResolver mPathResolver;
     QList<ReadWriteMessage> mMessages;
     QStringList mCategories = QStringList();
+    QgsProjectTranslator *mProjectTranslator;
 
     friend class QgsReadWriteContextCategoryPopper;
 };

src/core/qgsvectorlayer.cpp

@@ -1907,13 +1907,13 @@ bool QgsVectorLayer::readSymbology( const QDomNode &layerNode, QString &errorMes
       if ( !aliasElem.attribute( QStringLiteral( "name" ) ).isEmpty() )
       {
         //if it has alias
-        alias = QgsProject::instance()->translate( QStringLiteral( "project:layers:%1:fieldaliases" ).arg( layerNode.namedItem( QStringLiteral( "id" ) ).toElement().text() ), aliasElem.attribute( QStringLiteral( "name" ) ) );
+        alias = context.projectTranslator()->translate( QStringLiteral( "project:layers:%1:fieldaliases" ).arg( layerNode.namedItem( QStringLiteral( "id" ) ).toElement().text() ), aliasElem.attribute( QStringLiteral( "name" ) ) );
         QgsDebugMsgLevel( "context" + QStringLiteral( "project:layers:%1:fieldaliases" ).arg( layerNode.namedItem( QStringLiteral( "id" ) ).toElement().text() ) + " source " + aliasElem.attribute( QStringLiteral( "name" ) ), 1 );
       }
       else
       {
         //if it has no alias, it should be the fields translation
-        alias = QgsProject::instance()->translate( QStringLiteral( "project:layers:%1:fieldaliases" ).arg( layerNode.namedItem( QStringLiteral( "id" ) ).toElement().text() ), field );
+        alias = context.projectTranslator()->translate( QStringLiteral( "project:layers:%1:fieldaliases" ).arg( layerNode.namedItem( QStringLiteral( "id" ) ).toElement().text() ), field );
         QgsDebugMsgLevel( "context" + QStringLiteral( "project:layers:%1:fieldaliases" ).arg( layerNode.namedItem( QStringLiteral( "id" ) ).toElement().text() ) + " source " + field, 1 );
         //if it gets the exact field value, there has been no translation (or not even translation loaded) - so no alias should be generated;
         if ( alias == aliasElem.attribute( QStringLiteral( "field" ) ) )