Merge pull request #5350 from pblottiere/null_218

[bugfix] Properly update filter comboboxes of relation reference widget

Author: pblottiere

src/gui/editorwidgets/qgsrelationreferencewidget.cpp

@@ -310,6 +310,15 @@ void QgsRelationReferenceWidget::setForeignKey( const QVariant& value )
 void QgsRelationReferenceWidget::deleteForeignKey()
 {
   QVariant nullValue = QSettings().value( "qgis/nullValue", "NULL" );
+
+  // deactivate filter comboboxes
+  if ( mChainFilters && !mFilterComboBoxes.isEmpty() )
+  {
+    QComboBox *cb = mFilterComboBoxes.first();
+    cb->setCurrentIndex( 0 );
+    disableChainedComboBoxes( cb );
+  }
+
   if ( mReadOnlySelector )
   {
     QString nullText = "";
@@ -522,6 +531,13 @@ void QgsRelationReferenceWidget::init()
             mFilterCache[mFilterFields[i]][cf] << nf;
           }
         }
+
+        if ( !mFilterComboBoxes.isEmpty() )
+        {
+          QComboBox *cb = mFilterComboBoxes.first();
+          cb->setCurrentIndex( 0 );
+          disableChainedComboBoxes( cb );
+        }
       }
     }
     else

tests/src/gui/testqgsrelationreferencewidget.cpp

@@ -38,6 +38,7 @@ class TestQgsRelationReferenceWidget : public QObject
 
     void testChainFilter();
     void testChainFilterRefreshed();
+    void testChainFilterDeleteForeignKey();
 
   private:
     QgsVectorLayer* mLayer1;
@@ -220,5 +221,48 @@ void TestQgsRelationReferenceWidget::testChainFilterRefreshed()
   QCOMPARE( cbs[2]->currentText(), QString( "sleeve" ) );
 }
 
+void TestQgsRelationReferenceWidget::testChainFilterDeleteForeignKey()
+{
+  // init a relation reference widget
+  QStringList filterFields = QStringList() << "material" << "diameter" << "raccord";
+
+  QgsRelationReferenceWidget w( new QWidget() );
+  w.setChainFilters( true );
+  w.setFilterFields( filterFields );
+  w.setRelation( *mRelation, true );
+  w.init();
+
+  // check the default status of filter comboboxes
+  QList<QComboBox *> cbs = w.mFilterComboBoxes;
+
+  QCOMPARE( cbs[0]->currentText(), QString( "material" ) );
+  QCOMPARE( cbs[0]->isEnabled(), true );
+
+  QCOMPARE( cbs[1]->currentText(), QString( "diameter" ) );
+  QCOMPARE( cbs[1]->isEnabled(), false );
+
+  QCOMPARE( cbs[2]->currentText(), QString( "raccord" ) );
+  QCOMPARE( cbs[2]->isEnabled(), false );
+
+  // set a foreign key
+  w.setForeignKey( QVariant( 11 ) );
+
+  QCOMPARE( cbs[0]->currentText(), QString( "iron" ) );
+  QCOMPARE( cbs[1]->currentText(), QString( "120" ) );
+  QCOMPARE( cbs[2]->currentText(), QString( "sleeve" ) );
+
+  // delete the foreign key
+  w.deleteForeignKey();
+
+  QCOMPARE( cbs[0]->currentText(), QString( "material" ) );
+  QCOMPARE( cbs[0]->isEnabled(), true );
+
+  QCOMPARE( cbs[1]->currentText(), QString( "diameter" ) );
+  QCOMPARE( cbs[1]->isEnabled(), false );
+
+  QCOMPARE( cbs[2]->currentText(), QString( "raccord" ) );
+  QCOMPARE( cbs[2]->isEnabled(), false );
+}
+
 QTEST_MAIN( TestQgsRelationReferenceWidget )
 #include "testqgsrelationreferencewidget.moc"