QGIS/src/gui/editorwidgets/qgsvaluerelationwidgetwrapper.cpp

/***************************************************************************
    qgsvaluerelationwidgetwrapper.cpp
     --------------------------------------
    Date                 : 5.1.2014
    Copyright            : (C) 2014 Matthias Kuhn
    Email                : matthias 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.                                   *
 *                                                                         *
 ***************************************************************************/

#include "qgsvaluerelationwidgetwrapper.h"

#include "qgis.h"
#include "qgsfields.h"
#include "qgsproject.h"
#include "qgsvaluerelationwidgetfactory.h"
#include "qgsvectorlayer.h"
#include "qgsfilterlineedit.h"
#include "qgsfeatureiterator.h"
#include "qgsvaluerelationfieldformatter.h"

#include <QStringListModel>
#include <QCompleter>

QgsValueRelationWidgetWrapper::QgsValueRelationWidgetWrapper( QgsVectorLayer* vl, int fieldIdx, QWidget* editor, QWidget* parent )
    : QgsEditorWidgetWrapper( vl, fieldIdx, editor, parent )
    , mComboBox( nullptr )
    , mListWidget( nullptr )
    , mLineEdit( nullptr )
    , mLayer( nullptr )
{
}


QVariant QgsValueRelationWidgetWrapper::value() const
{
  QVariant v;

  if ( mComboBox )
  {
    int cbxIdx = mComboBox->currentIndex();
    if ( cbxIdx > -1 )
    {
      v = mComboBox->currentData();
    }
  }

  if ( mListWidget )
  {
    QStringList selection;
    for ( int i = 0; i < mListWidget->count(); ++i )
    {
      QListWidgetItem* item = mListWidget->item( i );
      if ( item->checkState() == Qt::Checked )
        selection << item->data( Qt::UserRole ).toString();
    }

    v = selection.join( QStringLiteral( "," ) ).prepend( '{' ).append( '}' );
  }

  if ( mLineEdit )
  {
    Q_FOREACH ( const QgsValueRelationFieldFormatter::ValueRelationItem& item , mCache )
    {
      if ( item.value == mLineEdit->text() )
      {
        v = item.value;
        break;
      }
    }
  }

  return v;
}

QWidget* QgsValueRelationWidgetWrapper::createWidget( QWidget* parent )
{
  if ( config( QStringLiteral( "AllowMulti" ) ).toBool() )
  {
    return new QListWidget( parent );
  }
  else if ( config( QStringLiteral( "UseCompleter" ) ).toBool() )
  {
    return new QgsFilterLineEdit( parent );
  }
  {
    return new QComboBox( parent );
  }
}

void QgsValueRelationWidgetWrapper::initWidget( QWidget* editor )
{
  mCache = QgsValueRelationFieldFormatter::createCache( config() );

  mComboBox = qobject_cast<QComboBox*>( editor );
  mListWidget = qobject_cast<QListWidget*>( editor );
  mLineEdit = qobject_cast<QLineEdit*>( editor );

  if ( mComboBox )
  {
    if ( config( QStringLiteral( "AllowNull" ) ).toBool() )
    {
      mComboBox->addItem( tr( "(no selection)" ), QVariant( field().type() ) );
    }

    Q_FOREACH ( const QgsValueRelationFieldFormatter::ValueRelationItem& element, mCache )
    {
      mComboBox->addItem( element.value, element.key );
    }

    connect( mComboBox, SIGNAL( currentIndexChanged( int ) ), this, SLOT( valueChanged() ) );
  }
  else if ( mListWidget )
  {
    Q_FOREACH ( const QgsValueRelationFieldFormatter::ValueRelationItem& element, mCache )
    {
      QListWidgetItem *item;
      item = new QListWidgetItem( element.value );
      item->setData( Qt::UserRole, element.key );

      mListWidget->addItem( item );
    }
    connect( mListWidget, SIGNAL( itemChanged( QListWidgetItem* ) ), this, SLOT( valueChanged() ) );
  }
  else if ( mLineEdit )
  {
    QStringList values;
    values.reserve( mCache.size() );
    Q_FOREACH ( const QgsValueRelationFieldFormatter::ValueRelationItem& i,  mCache )
    {
      values << i.value;
    }

    QStringListModel* m = new QStringListModel( values, mLineEdit );
    QCompleter* completer = new QCompleter( m, mLineEdit );
    completer->setCaseSensitivity( Qt::CaseInsensitive );
    mLineEdit->setCompleter( completer );
  }
}

bool QgsValueRelationWidgetWrapper::valid() const
{
  return mListWidget || mLineEdit || mComboBox;
}

void QgsValueRelationWidgetWrapper::setValue( const QVariant& value )
{
  if ( mListWidget )
  {
    QStringList checkList = value.toString().remove( QChar( '{' ) ).remove( QChar( '}' ) ).split( ',' );

    for ( int i = 0; i < mListWidget->count(); ++i )
    {
      QListWidgetItem* item = mListWidget->item( i );
      item->setCheckState( checkList.contains( item->data( Qt::UserRole ).toString() ) ? Qt::Checked : Qt::Unchecked );
    }
  }
  else if ( mComboBox )
  {
    mComboBox->setCurrentIndex( mComboBox->findData( value ) );
  }
  else if ( mLineEdit )
  {
    Q_FOREACH ( QgsValueRelationFieldFormatter::ValueRelationItem i, mCache )
    {
      if ( i.key == value )
      {
        mLineEdit->setText( i.value );
        break;
      }
    }
  }
}

void QgsValueRelationWidgetWrapper::showIndeterminateState()
{
  if ( mListWidget )
  {
    mListWidget->blockSignals( true );
    for ( int i = 0; i < mListWidget->count(); ++i )
    {
      mListWidget->item( i )->setCheckState( Qt::PartiallyChecked );
    }
    mListWidget->blockSignals( false );
  }
  else if ( mComboBox )
  {
    whileBlocking( mComboBox )->setCurrentIndex( -1 );
  }
  else if ( mLineEdit )
  {
    whileBlocking( mLineEdit )->clear();
  }
}