Add widget to edit QVariantMap

python/gui/gui.sip

@@ -95,6 +95,7 @@
 %Include qgshistogramwidget.sip
 %Include qgshtmlannotationitem.sip
 %Include qgsidentifymenu.sip
+%Include qgskeyvaluewidget.sip
 %Include qgslegendfilterbutton.sip
 %Include qgslegendinterface.sip
 %Include qgslimitedrandomcolorrampdialog.sip

python/gui/qgskeyvaluewidget.sip

@@ -0,0 +1,32 @@
+/** \ingroup gui
+ * Widget allowing to edit a QVariantMap, using a table.
+ * @note added in QGIS 3.0
+ */
+class QgsKeyValueWidget : public QWidget
+{
+%TypeHeaderCode
+#include "qgskeyvaluewidget.h"
+%End
+  public:
+    /**
+     * Constructor.
+     */
+    explicit QgsKeyValueWidget( QWidget* parent /TransferThis/ = 0 );
+
+    /**
+     * Set the initial value of the widget.
+     */
+    void setMap( const QVariantMap& map );
+
+    /**
+     * Get the edit value.
+     * @return the QVariantMap
+     */
+    QVariantMap map() const;
+
+  signals:
+    /**
+     * Emitted each time a key or a value is changed.
+     */
+    void valueChanged();
+};

src/gui/CMakeLists.txt

@@ -116,6 +116,8 @@ SET(QGIS_GUI_SRCS
   editorwidgets/qgsfilenamewidgetfactory.cpp
   editorwidgets/qgshiddenwidgetwrapper.cpp
   editorwidgets/qgshiddenwidgetfactory.cpp
+  editorwidgets/qgskeyvaluewidgetfactory.cpp
+  editorwidgets/qgskeyvaluewidgetwrapper.cpp
   editorwidgets/qgsmultiedittoolbutton.cpp
   editorwidgets/qgsphotoconfigdlg.cpp
   editorwidgets/qgsphotowidgetwrapper.cpp
@@ -231,6 +233,7 @@ SET(QGIS_GUI_SRCS
   qgshistogramwidget.cpp
   qgshtmlannotationitem.cpp
   qgsidentifymenu.cpp
+  qgskeyvaluewidget.cpp
   qgslegendfilterbutton.cpp
   qgslegendinterface.cpp
   qgslimitedrandomcolorrampdialog.cpp
@@ -388,6 +391,7 @@ SET(QGIS_GUI_MOC_HDRS
   qgshistogramwidget.h
   qgshtmlannotationitem.h
   qgsidentifymenu.h
+  qgskeyvaluewidget.h
   qgslegendfilterbutton.h
   qgslegendinterface.h
   qgslimitedrandomcolorrampdialog.h
@@ -561,6 +565,7 @@ SET(QGIS_GUI_MOC_HDRS
   editorwidgets/qgsexternalresourcewidgetwrapper.h
   editorwidgets/qgsfilenamewidgetwrapper.h
   editorwidgets/qgshiddenwidgetwrapper.h
+  editorwidgets/qgskeyvaluewidgetwrapper.h
   editorwidgets/qgsmultiedittoolbutton.h
   editorwidgets/qgsphotoconfigdlg.h
   editorwidgets/qgsphotowidgetwrapper.h
@@ -676,6 +681,7 @@ SET(QGIS_GUI_HDRS
   editorwidgets/qgsexternalresourcewidgetfactory.h
   editorwidgets/qgsfilenamewidgetfactory.h
   editorwidgets/qgshiddenwidgetfactory.h
+  editorwidgets/qgskeyvaluewidgetfactory.h
   editorwidgets/qgsphotowidgetfactory.h
   editorwidgets/qgsrangewidgetfactory.h
   editorwidgets/qgsrelationreferencefactory.h
@@ -731,6 +737,7 @@ SET(QGIS_GUI_UI_HDRS
   ${CMAKE_CURRENT_BINARY_DIR}/../ui/ui_qgsexpressionbuilder.h
   ${CMAKE_CURRENT_BINARY_DIR}/../ui/ui_qgsexpressionselectiondialogbase.h
   ${CMAKE_CURRENT_BINARY_DIR}/../ui/ui_qgsgenericprojectionselectorbase.h
+  ${CMAKE_CURRENT_BINARY_DIR}/../ui/ui_qgskeyvaluewidgetbase.h
   ${CMAKE_CURRENT_BINARY_DIR}/../ui/ui_qgsmessagelogviewer.h
   ${CMAKE_CURRENT_BINARY_DIR}/../ui/ui_qgsmessageviewer.h
   ${CMAKE_CURRENT_BINARY_DIR}/../ui/ui_qgsowssourceselectbase.h

src/gui/attributetable/qgsattributetabledelegate.cpp

@@ -72,6 +72,7 @@ QWidget* QgsAttributeTableDelegate::createEditor( QWidget *parent, const QStyleO
   QWidget* w = eww->widget();
 
   w->setAutoFillBackground( true );
+  w->setFocusPolicy( Qt::StrongFocus ); // to make sure QMouseEvents are propagated to the editor widget
 
   eww->setEnabled( !vl->editFormConfig().readOnly( fieldIdx ) );
 

src/gui/editorwidgets/core/qgseditorwidgetregistry.cpp

@@ -32,6 +32,7 @@
 #include "qgsexternalresourcewidgetfactory.h"
 #include "qgsfilenamewidgetfactory.h"
 #include "qgshiddenwidgetfactory.h"
+#include "qgskeyvaluewidgetfactory.h"
 #include "qgsphotowidgetfactory.h"
 #include "qgsrangewidgetfactory.h"
 #include "qgsrelationreferencefactory.h"
@@ -73,6 +74,7 @@ void QgsEditorWidgetRegistry::initEditors( QgsMapCanvas *mapCanvas, QgsMessageBa
   reg->registerWidget( "RelationReference", new QgsRelationReferenceFactory( tr( "Relation Reference" ), mapCanvas, messageBar ) );
   reg->registerWidget( "DateTime", new QgsDateTimeEditFactory( tr( "Date/Time" ) ) );
   reg->registerWidget( "ExternalResource", new QgsExternalResourceWidgetFactory( tr( "External Resource" ) ) );
+  reg->registerWidget( "KeyValue", new QgsKeyValueWidgetFactory( tr( "Key/Value" ) ) );
 }
 
 QgsEditorWidgetRegistry::QgsEditorWidgetRegistry()

src/gui/editorwidgets/qgshiddenwidgetwrapper.cpp

@@ -18,7 +18,7 @@
 #include <QWidget>
 
 QgsHiddenWidgetWrapper::QgsHiddenWidgetWrapper( QgsVectorLayer* vl, int fieldIdx, QWidget* editor, QWidget* parent )
-    :  QgsEditorWidgetWrapper( vl, fieldIdx, editor, parent )
+    : QgsEditorWidgetWrapper( vl, fieldIdx, editor, parent )
 {
 }
 

src/gui/editorwidgets/qgskeyvaluewidgetfactory.cpp

@@ -0,0 +1,96 @@
+/***************************************************************************
+    qgskeyvaluewidgetfactory.cpp
+     --------------------------------------
+    Date                 : 08.2016
+    Copyright            : (C) 2016 Patrick Valsecchi
+    Email                : patrick.valsecchi@camptocamp.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 "qgskeyvaluewidgetfactory.h"
+#include "qgskeyvaluewidgetwrapper.h"
+#include "qgsdummyconfigdlg.h"
+#include "qgsfield.h"
+#include "qgsvectorlayer.h"
+
+#include <QVariant>
+#include <QSettings>
+
+QgsKeyValueWidgetFactory::QgsKeyValueWidgetFactory( const QString& name ):
+    QgsEditorWidgetFactory( name )
+{
+}
+
+QgsEditorWidgetWrapper* QgsKeyValueWidgetFactory::create( QgsVectorLayer *vl, int fieldIdx, QWidget *editor, QWidget *parent ) const
+{
+  return new QgsKeyValueWidgetWrapper( vl, fieldIdx, editor, parent );
+}
+
+QgsEditorConfigWidget* QgsKeyValueWidgetFactory::configWidget( QgsVectorLayer *vl, int fieldIdx, QWidget *parent ) const
+{
+  Q_UNUSED( vl );
+  Q_UNUSED( fieldIdx );
+  Q_UNUSED( parent );
+  return new QgsDummyConfigDlg( vl, fieldIdx, parent, QObject::tr( "Key/Value field" ) );
+}
+
+QgsEditorWidgetConfig QgsKeyValueWidgetFactory::readConfig( const QDomElement &configElement, QgsVectorLayer *layer, int fieldIdx )
+{
+  Q_UNUSED( configElement );
+  Q_UNUSED( layer );
+  Q_UNUSED( fieldIdx );
+  return QgsEditorWidgetConfig();
+}
+
+void QgsKeyValueWidgetFactory::writeConfig( const QgsEditorWidgetConfig& config, QDomElement& configElement, QDomDocument& doc, const QgsVectorLayer* layer, int fieldIdx )
+{
+  Q_UNUSED( config );
+  Q_UNUSED( configElement );
+  Q_UNUSED( doc );
+  Q_UNUSED( layer );
+  Q_UNUSED( fieldIdx );
+}
+
+QString QgsKeyValueWidgetFactory::representValue( QgsVectorLayer* vl, int fieldIdx, const QgsEditorWidgetConfig& config, const QVariant& cache, const QVariant& value ) const
+{
+  Q_UNUSED( vl );
+  Q_UNUSED( fieldIdx );
+  Q_UNUSED( config );
+  Q_UNUSED( cache );
+
+  if ( value.isNull() )
+  {
+    QSettings settings;
+    return settings.value( "qgis/nullValue", "NULL" ).toString();
+  }
+
+  QString result;
+  const QVariantMap map = value.toMap();
+  for ( QVariantMap::const_iterator i = map.constBegin(); i != map.constEnd(); ++i )
+  {
+    if ( !result.isEmpty() ) result.append( ", " );
+    result.append( i.key() ).append( ": " ).append( i.value().toString() );
+  }
+  return result;
+}
+
+Qt::AlignmentFlag QgsKeyValueWidgetFactory::alignmentFlag( QgsVectorLayer *vl, int fieldIdx, const QgsEditorWidgetConfig &config ) const
+{
+  Q_UNUSED( vl );
+  Q_UNUSED( fieldIdx );
+  Q_UNUSED( config );
+
+  return Qt::AlignLeft;
+}
+
+unsigned int QgsKeyValueWidgetFactory::fieldScore( const QgsVectorLayer* vl, int fieldIdx ) const
+{
+  const QgsField field = vl->fields().field( fieldIdx );
+  return field.type() == QVariant::Map ? 20 : 0;
+}

src/gui/editorwidgets/qgskeyvaluewidgetfactory.h

@@ -0,0 +1,46 @@
+/***************************************************************************
+    qgskeyvaluewidgetfactory.h
+     --------------------------------------
+    Date                 : 08.2016
+    Copyright            : (C) 2016 Patrick Valsecchi
+    Email                : patrick.valsecchi@camptocamp.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.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#ifndef QGSKEYVALUEEDITFACTORY_H
+#define QGSKEYVALUEEDITFACTORY_H
+
+#include "qgseditorwidgetfactory.h"
+
+/** @ingroup gui
+ * Factory for widgets for editing a QVariantMap
+ * @note added in QGIS 3.0
+ * @note not available in Python bindings
+ */
+class GUI_EXPORT QgsKeyValueWidgetFactory : public QgsEditorWidgetFactory
+{
+  public:
+    /**
+     * Constructor.
+     */
+    QgsKeyValueWidgetFactory( const QString& name );
+
+    // QgsEditorWidgetFactory interface
+  public:
+    QgsEditorWidgetWrapper* create( QgsVectorLayer *vl, int fieldIdx, QWidget *editor, QWidget *parent ) const override;
+    //QgsSearchWidgetWrapper* createSearchWidget( QgsVectorLayer* vl, int fieldIdx, QWidget* parent ) const override;
+    QgsEditorConfigWidget* configWidget( QgsVectorLayer *vl, int fieldIdx, QWidget *parent ) const override;
+    QgsEditorWidgetConfig readConfig( const QDomElement &configElement, QgsVectorLayer *layer, int fieldIdx ) override;
+    void writeConfig( const QgsEditorWidgetConfig& config, QDomElement& configElement, QDomDocument& doc, const QgsVectorLayer* layer, int fieldIdx ) override;
+    QString representValue( QgsVectorLayer* vl, int fieldIdx, const QgsEditorWidgetConfig& config, const QVariant& cache, const QVariant& value ) const override;
+    Qt::AlignmentFlag alignmentFlag( QgsVectorLayer *vl, int fieldIdx, const QgsEditorWidgetConfig &config ) const override;
+    unsigned int fieldScore( const QgsVectorLayer* vl, int fieldIdx ) const override;
+};
+
+#endif // QGSKEYVALUEEDITFACTORY_H

src/gui/editorwidgets/qgskeyvaluewidgetwrapper.cpp

@@ -0,0 +1,85 @@
+/***************************************************************************
+    qgskeyvaluewidgetwrapper.cpp
+     --------------------------------------
+    Date                 : 08.2016
+    Copyright            : (C) 2016 Patrick Valsecchi
+    Email                : patrick.valsecchi@camptocamp.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 "qgskeyvaluewidgetwrapper.h"
+#include "qgskeyvaluewidget.h"
+#include "qgsattributeform.h"
+
+QgsKeyValueWidgetWrapper::QgsKeyValueWidgetWrapper( QgsVectorLayer* vl, int fieldIdx, QWidget* editor, QWidget* parent ):
+    QgsEditorWidgetWrapper( vl, fieldIdx, editor, parent ), mWidget( nullptr )
+{
+}
+
+QVariant QgsKeyValueWidgetWrapper::value() const
+{
+  if ( !mWidget ) return QVariant( QVariant::Map );
+  return mWidget->map();
+}
+
+void QgsKeyValueWidgetWrapper::showIndeterminateState()
+{
+  mWidget->setMap( QVariantMap() );
+}
+
+static bool isInTable( const QWidget* parent )
+{
+  if ( !parent ) return false;
+  if ( qobject_cast<const QTableView*>( parent ) ) return true;
+  return isInTable( parent->parentWidget() );
+}
+
+QWidget* QgsKeyValueWidgetWrapper::createWidget( QWidget* parent )
+{
+  if ( isInTable( parent ) )
+  {
+    // if to be put in a table, draw a border and set a decent size
+    QFrame* ret = new QFrame( parent );
+    ret->setFrameShape( QFrame::StyledPanel );
+    QHBoxLayout* layout = new QHBoxLayout( ret );
+    layout->addWidget( new QgsKeyValueWidget( ret ) );
+    ret->setMinimumSize( QSize( 320, 110 ) );
+    return ret;
+  }
+  else
+  {
+    return new QgsKeyValueWidget( parent );
+  }
+}
+
+void QgsKeyValueWidgetWrapper::initWidget( QWidget* editor )
+{
+  mWidget = qobject_cast<QgsKeyValueWidget*>( editor );
+  if ( !mWidget )
+  {
+    mWidget = editor->findChild<QgsKeyValueWidget*>();
+  }
+
+  connect( mWidget, SIGNAL( valueChanged( const QVariant& ) ), this, SIGNAL( valueChanged( const QVariant& ) ) );
+}
+
+bool QgsKeyValueWidgetWrapper::valid() const
+{
+  return true;
+}
+
+void QgsKeyValueWidgetWrapper::setValue( const QVariant& value )
+{
+  mWidget->setMap( value.toMap() );
+}
+
+void QgsKeyValueWidgetWrapper::updateConstraintWidgetStatus( bool /*constraintValid*/ )
+{
+  // Nothing
+}

src/gui/editorwidgets/qgskeyvaluewidgetwrapper.h

@@ -0,0 +1,56 @@
+/***************************************************************************
+    qgskeyvaluewidgetwrapper.h
+     --------------------------------------
+    Date                 : 08.2016
+    Copyright            : (C) 2016 Patrick Valsecchi
+    Email                : patrick.valsecchi@camptocamp.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.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#ifndef QGSKEYVALUEWIDGETWRAPPER_H
+#define QGSKEYVALUEWIDGETWRAPPER_H
+
+#include "qgseditorwidgetwrapper.h"
+
+class QgsKeyValueWidget;
+
+/** @ingroup gui
+ * Wraps a key/value widget.
+ * @note added in QGIS 3.0
+ * @note not available in Python bindings
+ */
+class GUI_EXPORT QgsKeyValueWidgetWrapper : public QgsEditorWidgetWrapper
+{
+    Q_OBJECT
+  public:
+    /**
+     * Constructor.
+     */
+    explicit QgsKeyValueWidgetWrapper( QgsVectorLayer* vl, int fieldIdx, QWidget* editor = nullptr, QWidget* parent = nullptr );
+
+    // QgsEditorWidgetWrapper interface
+  public:
+    QVariant value() const override;
+    void showIndeterminateState() override;
+
+  protected:
+    QWidget* createWidget( QWidget* parent ) override;
+    void initWidget( QWidget* editor ) override;
+    bool valid() const override;
+
+  public slots:
+    void setValue( const QVariant& value ) override;
+
+  private:
+    void updateConstraintWidgetStatus( bool constraintValid ) override;
+
+    QgsKeyValueWidget* mWidget;
+};
+
+#endif // QGSKEYVALUEWIDGETWRAPPER_H

src/gui/qgskeyvaluewidget.cpp

@@ -0,0 +1,174 @@
+/***************************************************************************
+    qgskeyvaluewidget.cpp
+     --------------------------------------
+    Date                 : 08.2016
+    Copyright            : (C) 2016 Patrick Valsecchi
+    Email                : patrick.valsecchi@camptocamp.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 "qgskeyvaluewidget.h"
+
+QgsKeyValueWidget::QgsKeyValueWidget( QWidget* parent )
+    : QWidget( parent )
+    , mModel( this )
+{
+  setupUi( this );
+  tableView->setModel( &mModel );
+  connect( tableView->selectionModel(), SIGNAL( selectionChanged( const QItemSelection &, const QItemSelection & ) ), this, SLOT( onSelectionChanged() ) );
+  connect( &mModel, SIGNAL( dataChanged( const QModelIndex&, const QModelIndex& ) ), this, SLOT( onValueChanged() ) );
+}
+
+void QgsKeyValueWidget::setMap( const QVariantMap& map )
+{
+  removeButton->setEnabled( false );
+  mModel.setMap( map );
+}
+
+void QgsKeyValueWidget::on_addButton_clicked()
+{
+  const QItemSelectionModel *select = tableView->selectionModel();
+  const int pos = select->hasSelection() ? select->selectedRows()[0].row() : 0;
+  mModel.insertRows( pos, 1 );
+  const QModelIndex index = mModel.index( pos, 0 );
+  tableView->scrollTo( index );
+  tableView->edit( index );
+  tableView->selectRow( pos );
+}
+
+void QgsKeyValueWidget::on_removeButton_clicked()
+{
+  const QItemSelectionModel *select = tableView->selectionModel();
+  // The UI is configured to have single row selection.
+  if ( select->hasSelection() )
+  {
+    mModel.removeRows( select->selectedRows()[0].row(), 1 );
+  }
+}
+
+void QgsKeyValueWidget::onSelectionChanged()
+{
+  removeButton->setEnabled( tableView->selectionModel()->hasSelection() );
+}
+
+void QgsKeyValueWidget::onValueChanged()
+{
+  emit valueChanged( QVariant( map() ) );
+}
+
+///@cond PRIVATE
+void QgsKeyValueModel::setMap( const QVariantMap& map )
+{
+  emit beginResetModel();
+  mLines.clear();
+  for ( QVariantMap::const_iterator it = map.constBegin(); it != map.constEnd(); ++it )
+  {
+    mLines.append( Line( it.key(), it.value() ) );
+  }
+  emit endResetModel();
+}
+
+QVariantMap QgsKeyValueModel::map() const
+{
+  QVariantMap ret;
+  for ( QVector<Line>::const_iterator it = mLines.constBegin(); it != mLines.constEnd(); ++it )
+  {
+    if ( !it->first.isEmpty() )
+    {
+      ret[it->first] = it->second;
+    }
+  }
+  return ret;
+}
+
+QgsKeyValueModel::QgsKeyValueModel( QObject *parent ) :
+    QAbstractTableModel( parent )
+{
+}
+
+int QgsKeyValueModel::rowCount( const QModelIndex& parent ) const
+{
+  Q_UNUSED( parent );
+  return mLines.count();
+}
+
+int QgsKeyValueModel::columnCount( const QModelIndex & parent ) const
+{
+  Q_UNUSED( parent );
+  return 2;
+}
+
+QVariant QgsKeyValueModel::headerData( int section, Qt::Orientation orientation, int role ) const
+{
+  if ( orientation == Qt::Horizontal && role == Qt::DisplayRole )
+  {
+    return QObject::tr( section == 0 ? "Key" : "Value" );
+  }
+  return QVariant();
+}
+
+QVariant QgsKeyValueModel::data( const QModelIndex& index, int role ) const
+{
+  if ( index.row() < 0 ||
+       index.row() >= mLines.count() ||
+       ( role != Qt::DisplayRole && role != Qt::EditRole ) )
+  {
+    return QVariant();
+  }
+  if ( index.column() == 0 )
+    return mLines.at( index.row() ).first;
+  if ( index.column() == 1 )
+    return mLines.at( index.row() ).second;
+  return QVariant();
+}
+
+bool QgsKeyValueModel::setData( const QModelIndex & index, const QVariant & value, int role )
+{
+  if ( index.row() < 0 || index.row() >= mLines.count() || role != Qt::EditRole )
+  {
+    return false;
+  }
+  if ( index.column() == 0 )
+  {
+    mLines[index.row()].first = value.toString();
+  }
+  else
+  {
+    mLines[index.row()].second = value;
+  }
+  emit dataChanged( index, index );
+  return true;
+}
+
+Qt::ItemFlags QgsKeyValueModel::flags( const QModelIndex &index ) const
+{
+  return QAbstractTableModel::flags( index ) | Qt::ItemIsEditable;
+}
+
+bool QgsKeyValueModel::insertRows( int position, int rows, const QModelIndex & parent )
+{
+  Q_UNUSED( parent );
+  beginInsertRows( QModelIndex(), position, position + rows - 1 );
+  for ( int i = 0; i < rows; ++i )
+  {
+    mLines.insert( position, Line( "", QVariant() ) );
+  }
+  endInsertRows();
+  return true;
+}
+
+bool QgsKeyValueModel::removeRows( int position, int rows, const QModelIndex &parent )
+{
+  Q_UNUSED( parent );
+  beginRemoveRows( QModelIndex(), position, position + rows - 1 );
+  mLines.remove( position, rows );
+  endRemoveRows();
+  return true;
+}
+///@endcond

src/gui/qgskeyvaluewidget.h

@@ -0,0 +1,103 @@
+/***************************************************************************
+    qgskeyvaluewidget.h
+     --------------------------------------
+    Date                 : 08.2016
+    Copyright            : (C) 2016 Patrick Valsecchi
+    Email                : patrick.valsecchi@camptocamp.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.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#ifndef QGSKEYVALUEWIDGET_H
+#define QGSKEYVALUEWIDGET_H
+
+#include "ui_qgskeyvaluewidgetbase.h"
+#include <QAbstractTableModel>
+#include <QMap>
+
+///@cond PRIVATE
+/** @ingroup gui
+ * Table model to edit a QVariantMap.
+ * @note added in QGIS 3.0
+ * @note not available in Python bindings
+ */
+class GUI_EXPORT QgsKeyValueModel : public QAbstractTableModel
+{
+    Q_OBJECT
+  public:
+
+    explicit QgsKeyValueModel( QObject *parent = 0 );
+    void setMap( const QVariantMap& map );
+    QVariantMap map() const;
+
+    int rowCount( const QModelIndex& parent = QModelIndex() ) const override;
+    int columnCount( const QModelIndex& parent = QModelIndex() ) const override;
+    QVariant headerData( int section, Qt::Orientation orientation, int role ) const override;
+    QVariant data( const QModelIndex& index, int role = Qt::DisplayRole ) const override;
+    bool setData( const QModelIndex & index, const QVariant & value, int role = Qt::EditRole ) override;
+    Qt::ItemFlags flags( const QModelIndex &index ) const override;
+    bool insertRows( int position, int rows, const QModelIndex & parent =  QModelIndex() ) override;
+    bool removeRows( int position, int rows, const QModelIndex &parent =  QModelIndex() ) override;
+
+    typedef QPair<QString, QVariant> Line;
+
+  private:
+    QVector<Line> mLines;
+};
+///@endcond
+
+
+/** \ingroup gui
+ * Widget allowing to edit a QVariantMap, using a table.
+ * @note added in QGIS 3.0
+ */
+class GUI_EXPORT QgsKeyValueWidget: public QWidget, public Ui::QgsKeyValueWidgetBase
+{
+    Q_OBJECT
+    Q_PROPERTY( QVariantMap map READ map WRITE setMap )
+  public:
+    /**
+     * Constructor.
+     */
+    explicit QgsKeyValueWidget( QWidget* parent = nullptr );
+
+    /**
+     * Set the initial value of the widget.
+     */
+    void setMap( const QVariantMap& map );
+
+    /**
+     * Get the edit value.
+     * @return the QVariantMap
+     */
+    QVariantMap map() const { return mModel.map(); }
+
+  signals:
+    /**
+     * Emitted each time a key or a value is changed.
+     * @param value the new value
+     */
+    void valueChanged( const QVariant& value );
+
+  private slots:
+    void on_addButton_clicked();
+    void on_removeButton_clicked();
+
+    /**
+     * Called when the selection is changed to enable/disable the delete button.
+     */
+    void onSelectionChanged();
+
+    void onValueChanged();
+
+  private:
+    QgsKeyValueModel mModel;
+};
+
+
+#endif // QGSKEYVALUEWIDGET_H

src/ui/qgskeyvaluewidgetbase.ui

@@ -0,0 +1,105 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>QgsKeyValueWidgetBase</class>
+ <widget class="QWidget" name="QgsKeyValueWidgetBase">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>426</width>
+    <height>112</height>
+   </rect>
+  </property>
+  <property name="minimumSize">
+   <size>
+    <width>300</width>
+    <height>82</height>
+   </size>
+  </property>
+  <property name="windowTitle">
+   <string>Form</string>
+  </property>
+  <layout class="QHBoxLayout" name="horizontalLayout_3">
+   <property name="margin">
+    <number>0</number>
+   </property>
+   <item>
+    <layout class="QVBoxLayout" name="verticalLayout">
+     <item>
+      <widget class="QToolButton" name="addButton">
+       <property name="toolTip">
+        <string>Add entry</string>
+       </property>
+       <property name="text">
+        <string>...</string>
+       </property>
+       <property name="icon">
+        <iconset resource="../../../images/images.qrc">
+         <normaloff>:/images/themes/default/mActionAdd.svg</normaloff>:/images/themes/default/mActionAdd.svg</iconset>
+       </property>
+      </widget>
+     </item>
+     <item>
+      <widget class="QToolButton" name="removeButton">
+       <property name="enabled">
+        <bool>false</bool>
+       </property>
+       <property name="toolTip">
+        <string>Remove entry</string>
+       </property>
+       <property name="text">
+        <string>...</string>
+       </property>
+       <property name="icon">
+        <iconset resource="../../../images/images.qrc">
+         <normaloff>:/images/themes/default/mActionRemove.svg</normaloff>:/images/themes/default/mActionRemove.svg</iconset>
+       </property>
+      </widget>
+     </item>
+     <item>
+      <spacer name="verticalSpacer">
+       <property name="orientation">
+        <enum>Qt::Vertical</enum>
+       </property>
+       <property name="sizeHint" stdset="0">
+        <size>
+         <width>20</width>
+         <height>40</height>
+        </size>
+       </property>
+      </spacer>
+     </item>
+    </layout>
+   </item>
+   <item>
+    <widget class="QTableView" name="tableView">
+     <property name="frameShape">
+      <enum>QFrame::NoFrame</enum>
+     </property>
+     <property name="editTriggers">
+      <set>QAbstractItemView::AnyKeyPressed|QAbstractItemView::CurrentChanged|QAbstractItemView::DoubleClicked|QAbstractItemView::EditKeyPressed</set>
+     </property>
+     <property name="selectionMode">
+      <enum>QAbstractItemView::SingleSelection</enum>
+     </property>
+     <property name="selectionBehavior">
+      <enum>QAbstractItemView::SelectRows</enum>
+     </property>
+     <property name="sortingEnabled">
+      <bool>false</bool>
+     </property>
+     <attribute name="horizontalHeaderStretchLastSection">
+      <bool>true</bool>
+     </attribute>
+     <attribute name="verticalHeaderVisible">
+      <bool>false</bool>
+     </attribute>
+    </widget>
+   </item>
+  </layout>
+ </widget>
+ <resources>
+  <include location="../../../images/images.qrc"/>
+ </resources>
+ <connections/>
+</ui>

tests/src/gui/CMakeLists.txt

@@ -141,4 +141,5 @@ ADD_QGIS_TEST(scalecombobox testqgsscalecombobox.cpp)
 ADD_QGIS_TEST(spinbox testqgsspinbox.cpp)
 ADD_QGIS_TEST(sqlcomposerdialog testqgssqlcomposerdialog.cpp)
 ADD_QGIS_TEST(editorwidgetregistrytest testqgseditorwidgetregistry.cpp)
+ADD_QGIS_TEST(keyvaluewidgettest testqgskeyvaluewidget.cpp)
 

tests/src/gui/testqgskeyvaluewidget.cpp

@@ -0,0 +1,76 @@
+/***************************************************************************
+    testqgskeyvaluewidget.cpp
+     --------------------------------------
+    Date                 : 08 09 2016
+    Copyright            : (C) 2016 Patrick Valsecchi
+    Email                : patrick dot valsecchi at camptocamp 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 <editorwidgets/qgskeyvaluewidgetfactory.h>
+#include <qgskeyvaluewidget.h>
+#include <editorwidgets/core/qgseditorwidgetwrapper.h>
+#include <qgsapplication.h>
+
+class TestQgsKeyValueWidget : public QObject
+{
+    Q_OBJECT
+  public:
+
+  private slots:
+    void initTestCase() // will be called before the first testfunction is executed.
+    {
+      QgsApplication::init();
+      QgsApplication::initQgis();
+    }
+
+    void cleanupTestCase() // will be called after the last testfunction was executed.
+    {
+      QgsApplication::exitQgis();
+    }
+
+    void testUpdate()
+    {
+      const QgsKeyValueWidgetFactory factory( "testKeyValue" );
+      QgsEditorWidgetWrapper* wrapper = factory.create( nullptr, 0, nullptr, nullptr );
+      QVERIFY( wrapper );
+      QSignalSpy spy( wrapper, SIGNAL( valueChanged( const QVariant& ) ) );
+
+      QgsKeyValueWidget* widget = qobject_cast< QgsKeyValueWidget* >( wrapper->widget() );
+      QVERIFY( widget );
+
+      QVariantMap initial;
+      initial["1"] = "one";
+      initial["2"] = "two";
+      wrapper->setValue( initial );
+
+      const QVariant value = wrapper->value();
+      QCOMPARE( int( value.type() ), int( QVariant::Map ) );
+      QCOMPARE( value.toMap(), initial );
+      QCOMPARE( spy.count(), 0 );
+
+      QAbstractItemModel* model = widget->tableView->model();
+      model->setData( model->index( 0, 1 ), "hello" );
+      QCOMPARE( spy.count(), 1 );
+
+      QVariantMap expected = initial;
+      expected["1"] = "hello";
+      QVariant eventValue = spy.at( 0 ).at( 0 ).value<QVariant>();
+      QCOMPARE( int( eventValue.type() ), int( QVariant::Map ) );
+      QCOMPARE( eventValue.toMap(), expected );
+      QCOMPARE( wrapper->value().toMap(), expected );
+      QCOMPARE( spy.count(), 1 );
+    }
+};
+
+QTEST_MAIN( TestQgsKeyValueWidget )
+#include "testqgskeyvaluewidget.moc"