extend QgsSettings::enumSettingValue to handle flags (with test)

3nids · 3nids · commit 4d6b0e6aeac3 · 2018-02-19T05:55:09.000-09:00
diff --git a/src/core/qgssettings.h b/src/core/qgssettings.h
@@ -224,17 +224,27 @@ class CORE_EXPORT QgsSettings : public QObject
      * Return the setting value for a setting based on an enum.
      * This forces the output to be a valid and existing entry of the enum.
      * Hence if the setting value is incorrect, the given default value is returned.
-     * \note The enum needs to be declared with Q_ENUM
+     * If \a flag is true, the value is checked for a flag definition.
+     * \note The enum needs to be declared with Q_ENUM, and flags with Q_FLAG (not Q_FLAGS).
      */
     template <class T>
     T enumSettingValue( const QString &key, const T &defaultValue,
-                        const Section section = NoSection ) const
+                        const Section section = NoSection, bool flag = false ) const
     {
-      T v = static_cast<T>( value( key, static_cast<int>( defaultValue ), section ).toInt() );
+      T v;
+      if ( !flag )
+        v = static_cast<T>( value( key, static_cast<int>( defaultValue ), section ).toInt() );
+      else
+        v = T( value( key, static_cast<int>( defaultValue ), section ).toInt() );
+
       QMetaEnum metaEnum = QMetaEnum::fromType<T>();
       if ( metaEnum.isValid() )
       {
-        if ( !metaEnum.valueToKey( static_cast<int>( v ) ) )
+        if ( !flag && !metaEnum.valueToKey( static_cast<int>( v ) ) )
+        {
+          v = defaultValue;
+        }
+        else if ( flag && !metaEnum.valueToKeys( static_cast<int>( v ) ).size() )
         {
           v = defaultValue;
         }
diff --git a/tests/src/core/testqgssettings.cpp b/tests/src/core/testqgssettings.cpp
@@ -17,6 +17,7 @@
 
 #include "qgssettings.h"
 #include "qgsunittypes.h"
+#include "qgsmaplayerproxymodel.h"
 #include "qgstest.h"
 
 
@@ -50,9 +51,21 @@ void TestQgsSettings::enumSettingValue()
   QgsUnitTypes::LayoutUnit v2 = settings.enumSettingValue( QStringLiteral( "qgis/testing/my_value_for_units" ), QgsUnitTypes::LayoutMeters );
   QCOMPARE( v2, QgsUnitTypes::LayoutMeters );
 
+  // test a different value than default
   settings.setValue( QStringLiteral( "qgis/testing/my_value_for_units" ), QgsUnitTypes::LayoutCentimeters );
   QgsUnitTypes::LayoutUnit v3 = settings.enumSettingValue( QStringLiteral( "qgis/testing/my_value_for_units" ), QgsUnitTypes::LayoutMeters );
   QCOMPARE( v3, QgsUnitTypes::LayoutCentimeters );
+
+  // test for flags
+  QgsMapLayerProxyModel::Filters pointAndLine = QgsMapLayerProxyModel::Filters( QgsMapLayerProxyModel::PointLayer | QgsMapLayerProxyModel::LineLayer );
+  QgsMapLayerProxyModel::Filters pointAndPolygon = QgsMapLayerProxyModel::Filters( QgsMapLayerProxyModel::PointLayer | QgsMapLayerProxyModel::PolygonLayer );
+  settings.setValue( QStringLiteral( "qgis/testing/my_value_for_a_flag" ), 1e8 ); // invalid
+  QgsMapLayerProxyModel::Filters v4 = settings.enumSettingValue( QStringLiteral( "qgis/testing/my_value_for_a_flag" ), pointAndLine );
+  QCOMPARE( v4, pointAndLine );
+
+  settings.setValue( QStringLiteral( "qgis/testing/my_value_for_a_flag" ), static_cast<int>( pointAndPolygon ) );
+  QgsMapLayerProxyModel::Filters v5 = settings.enumSettingValue( QStringLiteral( "qgis/testing/my_value_for_a_flag" ), pointAndLine, QgsSettings::NoSection, true );
+  QCOMPARE( v5, pointAndPolygon );
 }
 
 
