Merge pull request #4925 from pblottiere/bugfix_scrolllocked_218

Fixes value relation widget to keep scrollbar activated, fixes #16654 (backport)

src/gui/editorwidgets/core/qgseditorwidgetwrapper.h

@@ -103,7 +103,7 @@ class GUI_EXPORT QgsEditorWidgetWrapper : public QgsWidgetWrapper
      *
      * @param enabled  Enable or Disable?
      */
-    void setEnabled( bool enabled ) override;
+    virtual void setEnabled( bool enabled ) override;
 
     /** Sets the widget to display in an indeterminate "mixed value" state.
      * @note added in QGIS 2.16

src/gui/editorwidgets/qgsvaluerelationwidgetwrapper.cpp

@@ -43,6 +43,7 @@ QgsValueRelationWidgetWrapper::QgsValueRelationWidgetWrapper( QgsVectorLayer* vl
     , mListWidget( nullptr )
     , mLineEdit( nullptr )
     , mLayer( nullptr )
+    , mUpdating( false )
 {
 }
 
@@ -248,3 +249,26 @@ void QgsValueRelationWidgetWrapper::showIndeterminateState()
     whileBlocking( mLineEdit )->clear();
   }
 }
+
+void QgsValueRelationWidgetWrapper::setEnabled( bool enabled )
+{
+  if ( mUpdating )
+    return;
+
+  if ( mListWidget )
+  {
+    mUpdating = true;
+    for ( int i = 0; i < mListWidget->count(); ++i )
+    {
+      QListWidgetItem *item = mListWidget->item( i );
+
+      if ( enabled )
+        item->setFlags( item->flags() | Qt::ItemIsEnabled );
+      else
+        item->setFlags( item->flags() & ~Qt::ItemIsEnabled );
+    }
+    mUpdating = false;
+  }
+  else
+    QgsEditorWidgetWrapper::setEnabled( enabled );
+}

src/gui/editorwidgets/qgsvaluerelationwidgetwrapper.h

@@ -68,6 +68,8 @@ class GUI_EXPORT QgsValueRelationWidgetWrapper : public QgsEditorWidgetWrapper
     static ValueRelationCache createCache( const QgsEditorWidgetConfig& config );
     void showIndeterminateState() override;
 
+    void setEnabled( bool enabled ) override;
+
   protected:
     QWidget* createWidget( QWidget* parent ) override;
     void initWidget( QWidget* editor ) override;
@@ -84,7 +86,10 @@ class GUI_EXPORT QgsValueRelationWidgetWrapper : public QgsEditorWidgetWrapper
     ValueRelationCache mCache;
     QgsVectorLayer* mLayer;
 
+    bool mUpdating;
+
     friend class QgsValueRelationWidgetFactory;
+    friend class TestQgsValueRelationWidgetWrapper;
 };
 
 Q_DECLARE_METATYPE( QgsValueRelationWidgetWrapper::ValueRelationCache )

tests/src/gui/CMakeLists.txt

@@ -144,4 +144,4 @@ ADD_QGIS_TEST(spinbox testqgsspinbox.cpp)
 ADD_QGIS_TEST(sqlcomposerdialog testqgssqlcomposerdialog.cpp)
 ADD_QGIS_TEST(filedownloader testqgsfiledownloader.cpp)
 ADD_QGIS_TEST(composergui testqgscomposergui.cpp)
-
+ADD_QGIS_TEST(valuerelationwidgetwrapper testqgsvaluerelationwidgetwrapper.cpp)

tests/src/gui/testqgsvaluerelationwidgetwrapper.cpp

@@ -0,0 +1,107 @@
+/***************************************************************************
+    testqgsvaluerelationwidgetwrapper.cpp
+     --------------------------------------
+    Date                 : 21 07 2017
+    Copyright            : (C) 2017 Paul Blottiere
+    Email                : paul dot blottiere at oslandia dot com
+ ***************************************************************************
+ *                                                                         *
+ *   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.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#include <QtTest/QtTest>
+#include <QScrollBar>
+
+#include <editorwidgets/core/qgseditorwidgetregistry.h>
+#include <qgsapplication.h>
+#include <qgsproject.h>
+#include <qgsvectorlayer.h>
+#include "qgseditorwidgetwrapper.h"
+#include <editorwidgets/qgsvaluerelationwidgetwrapper.h>
+
+class TestQgsValueRelationWidgetWrapper : public QObject
+{
+    Q_OBJECT
+  public:
+    TestQgsValueRelationWidgetWrapper() {}
+
+  private slots:
+    void initTestCase(); // will be called before the first testfunction is executed.
+    void cleanupTestCase(); // will be called after the last testfunction was executed.
+    void init(); // will be called before each testfunction is executed.
+    void cleanup(); // will be called after every testfunction.
+
+    void testScrollBarUnlocked();
+};
+
+void TestQgsValueRelationWidgetWrapper::initTestCase()
+{
+  QgsApplication::init();
+  QgsApplication::initQgis();
+  QgsEditorWidgetRegistry::initEditors();
+}
+
+void TestQgsValueRelationWidgetWrapper::cleanupTestCase()
+{
+  QgsApplication::exitQgis();
+}
+
+void TestQgsValueRelationWidgetWrapper::init()
+{
+}
+
+void TestQgsValueRelationWidgetWrapper::cleanup()
+{
+}
+
+void TestQgsValueRelationWidgetWrapper::testScrollBarUnlocked()
+{
+  // create a vector layer
+  QgsVectorLayer vl1( QString( "LineString?crs=epsg:3111&field=pk:int&field=fk|:int" ), QString( "vl1" ), QString( "memory" ) );
+
+  // build a value relation widget wrapper
+  QListWidget lw;
+  QWidget editor;
+  QgsValueRelationWidgetWrapper w( &vl1, 0, &editor, nullptr );
+  w.setEnabled( true );
+  w.initWidget( &lw );
+
+  // add an item virtually
+  QListWidgetItem item;
+  item.setText( "MyText" );
+  w.mListWidget->addItem( &item );
+  QCOMPARE( w.mListWidget->item( 0 )->text(), QString( "MyText" ) );
+
+  // when the widget wrapper is enabled, the container should be enabled
+  // as well as items
+  w.setEnabled( true );
+
+  QCOMPARE( w.widget()->isEnabled(), true );
+
+  bool itemEnabled = w.mListWidget->item( 0 )->flags() & Qt::ItemIsEnabled;
+  QCOMPARE( itemEnabled, true );
+
+  // when the widget wrapper is disabled, the container should still be enabled
+  // to keep the scrollbar available but items should be disabled to avoid
+  // edition
+  w.setEnabled( false );
+
+  itemEnabled = w.mListWidget->item( 0 )->flags() & Qt::ItemIsEnabled;
+  QCOMPARE( itemEnabled, false );
+
+  QCOMPARE( w.widget()->isEnabled(), true );
+
+  // recheck after re-enabled
+  w.setEnabled( true );
+
+  QCOMPARE( w.widget()->isEnabled(), true );
+  itemEnabled = w.mListWidget->item( 0 )->flags() & Qt::ItemIsEnabled;
+  QCOMPARE( itemEnabled, true );
+}
+
+QTEST_MAIN( TestQgsValueRelationWidgetWrapper )
+#include "testqgsvaluerelationwidgetwrapper.moc"