C++ const_iterator::value方法代码示例

bool QgsMemoryProvider::changeAttributeValues( const QgsChangedAttributesMap & attr_map )
{
  for ( QgsChangedAttributesMap::const_iterator it = attr_map.begin(); it != attr_map.end(); ++it )
  {
    QgsFeatureMap::iterator fit = mFeatures.find( it.key() );
    if ( fit == mFeatures.end() )
      continue;

    const QgsAttributeMap& attrs = it.value();
    for ( QgsAttributeMap::const_iterator it2 = attrs.begin(); it2 != attrs.end(); ++it2 )
      fit->changeAttribute( it2.key(), it2.value() );
  }
  return TRUE;
}

QgsVectorLayerUndoCommandDeleteAttribute::QgsVectorLayerUndoCommandDeleteAttribute( QgsVectorLayerEditBuffer* buffer, int fieldIndex )
    : QgsVectorLayerUndoCommand( buffer )
    , mFieldIndex( fieldIndex )
{
  const QgsFields& fields = layer()->fields();
  QgsFields::FieldOrigin origin = fields.fieldOrigin( mFieldIndex );
  mOriginIndex = fields.fieldOriginIndex( mFieldIndex );
  mProviderField = ( origin == QgsFields::OriginProvider );
  mFieldName = fields.field( mFieldIndex ).name();
  mOldEditorWidgetConfig = mBuffer->L->editFormConfig().widgetConfig( mFieldName );

  if ( !mProviderField )
  {
    // need to store the field definition
    mOldField = mBuffer->mAddedAttributes[mOriginIndex];
  }

  if ( mBuffer->mRenamedAttributes.contains( fieldIndex ) )
  {
    mOldName = mBuffer->mRenamedAttributes.value( fieldIndex );
  }

  // save values of new features
  for ( QgsFeatureMap::const_iterator it = mBuffer->mAddedFeatures.constBegin(); it != mBuffer->mAddedFeatures.constEnd(); ++it )
  {
    const QgsFeature& f = it.value();
    mDeletedValues.insert( f.id(), f.attribute( mFieldIndex ) );
  }

  // save changed values
  for ( QgsChangedAttributesMap::const_iterator it = mBuffer->mChangedAttributeValues.constBegin(); it != mBuffer->mChangedAttributeValues.constEnd(); ++it )
  {
    const QgsAttributeMap& attrs = it.value();
    if ( attrs.contains( mFieldIndex ) )
      mDeletedValues.insert( it.key(), attrs[mFieldIndex] );
  }
}

void QgsOfflineEditing::committedAttributeValuesChanges( const QString& qgisLayerId, const QgsChangedAttributesMap& changedAttrsMap )
{
  sqlite3* db = openLoggingDb();
  if ( db == NULL )
  {
    return;
  }

  // insert log
  int layerId = getOrCreateLayerId( db, qgisLayerId );
  int commitNo = getCommitNo( db );

  for ( QgsChangedAttributesMap::const_iterator cit = changedAttrsMap.begin(); cit != changedAttrsMap.end(); ++cit )
  {
    QgsFeatureId fid = cit.key();
    if ( isAddedFeature( db, layerId, fid ) )
    {
      // skip added features
      continue;
    }
    QgsAttributeMap attrMap = cit.value();
    for ( QgsAttributeMap::const_iterator it = attrMap.begin(); it != attrMap.end(); ++it )
    {
      QString sql = QString( "INSERT INTO 'log_feature_updates' VALUES ( %1, %2, %3, %4, '%5' )" )
                    .arg( layerId )
                    .arg( commitNo )
                    .arg( fid )
                    .arg( it.key() ) // attr
                    .arg( it.value().toString() ); // value
      sqlExec( db, sql );
    }
  }

  increaseCommitNo( db );
  sqlite3_close( db );
}

bool QgsWFSProvider::changeAttributeValues( const QgsChangedAttributesMap &attr_map )
{
  //find out typename from uri and strip namespace prefix
  QString tname = mShared->mURI.typeName();
  if ( tname.isNull() )
  {
    return false;
  }

  //create <Transaction> xml
  QDomDocument transactionDoc;
  QDomElement transactionElem = createTransactionElement( transactionDoc );
  transactionDoc.appendChild( transactionElem );

  QgsChangedAttributesMap::const_iterator attIt = attr_map.constBegin();
  for ( ; attIt != attr_map.constEnd(); ++attIt )
  {
    QString gmlid = mShared->findGmlId( attIt.key() );
    if ( gmlid.isEmpty() )
    {
      QgsDebugMsg( QString( "Cannot identify feature of id %1" ).arg( attIt.key() ) );
      continue;
    }

    QDomElement updateElem = transactionDoc.createElementNS( QgsWFSConstants::WFS_NAMESPACE, "Update" );
    updateElem.setAttribute( "typeName", tname );

    QgsAttributeMap::const_iterator attMapIt = attIt.value().constBegin();
    for ( ; attMapIt != attIt.value().constEnd(); ++attMapIt )
    {
      QString fieldName = mShared->mFields.at( attMapIt.key() ).name();
      QDomElement propertyElem = transactionDoc.createElementNS( QgsWFSConstants::WFS_NAMESPACE, "Property" );

      QDomElement nameElem = transactionDoc.createElementNS( QgsWFSConstants::WFS_NAMESPACE, "Name" );
      QDomText nameText = transactionDoc.createTextNode( fieldName );
      nameElem.appendChild( nameText );
      propertyElem.appendChild( nameElem );

      QDomElement valueElem = transactionDoc.createElementNS( QgsWFSConstants::WFS_NAMESPACE, "Value" );
      QDomText valueText = transactionDoc.createTextNode( attMapIt.value().toString() );
      valueElem.appendChild( valueText );
      propertyElem.appendChild( valueElem );

      updateElem.appendChild( propertyElem );
    }

    //Filter
    QDomElement filterElem = transactionDoc.createElementNS( QgsWFSConstants::OGC_NAMESPACE, "Filter" );
    QDomElement featureIdElem = transactionDoc.createElementNS( QgsWFSConstants::OGC_NAMESPACE, "FeatureId" );
    featureIdElem.setAttribute( "fid", gmlid );
    filterElem.appendChild( featureIdElem );
    updateElem.appendChild( filterElem );

    transactionElem.appendChild( updateElem );
  }

  QDomDocument serverResponse;
  bool success = sendTransactionDocument( transactionDoc, serverResponse );
  if ( !success )
  {
    return false;
  }

  if ( transactionSuccess( serverResponse ) )
  {
    mShared->changeAttributeValues( attr_map );
    return true;
  }
  else
  {
    handleException( serverResponse );
    return false;
  }
}

bool QgsDb2Provider::changeAttributeValues( const QgsChangedAttributesMap &attr_map )
{
  QgsDebugMsg( "Entering" );
  if ( attr_map.isEmpty() )
    return true;

  if ( mFidColName.isEmpty() )
    return false;

  for ( QgsChangedAttributesMap::const_iterator it = attr_map.begin(); it != attr_map.end(); ++it )
  {
    QgsFeatureId fid = it.key();

    // skip added features
    if ( FID_IS_NEW( fid ) )
      continue;

    const QgsAttributeMap& attrs = it.value();
    if ( attrs.isEmpty() )
      continue;

    QString statement = QString( "UPDATE %1.%2 SET " ).arg( mSchemaName, mTableName );

    bool first = true;
    if ( !mDatabase.isOpen() )
    {
      QString errMsg;
      mDatabase = getDatabase( mConnInfo, errMsg );
      if ( !errMsg.isEmpty() )
      {
        return false;
      }
    }
    QSqlQuery query = QSqlQuery( mDatabase );
    query.setForwardOnly( true );

    for ( QgsAttributeMap::const_iterator it2 = attrs.begin(); it2 != attrs.end(); ++it2 )
    {
      QgsField fld = mAttributeFields.at( it2.key() );

      if ( fld.typeName().endsWith( " identity", Qt::CaseInsensitive ) )
        continue; // skip identity field

      if ( fld.name().isEmpty() )
        continue; // invalid

      if ( !first )
        statement += ',';
      else
        first = false;

      statement += QString( "%1=?" ).arg( fld.name() );
    }

    if ( first )
      return true; // no fields have been changed

    // set attribute filter
    statement += QString( " WHERE %1=%2" ).arg( mFidColName, FID_TO_STRING( fid ) );

    // use prepared statement to prevent from sql injection
    if ( !query.prepare( statement ) )
    {
      QgsDebugMsg( query.lastError().text() );
      return false;
    }
    QgsDebugMsg( statement );
    for ( QgsAttributeMap::const_iterator it2 = attrs.begin(); it2 != attrs.end(); ++it2 )
    {
      QgsField fld = mAttributeFields.at( it2.key() );

      if ( fld.name().isEmpty() )
        continue; // invalid

      QVariant::Type type = fld.type();
      if ( it2->isNull() || !it2->isValid() )
      {
        // binding null values
        if ( type == QVariant::Date || type == QVariant::DateTime )
          query.addBindValue( QVariant( QVariant::String ) );
        else
          query.addBindValue( QVariant( type ) );
      }
      else if ( type == QVariant::Int )
      {
        // binding an INTEGER value
        query.addBindValue( it2->toInt() );
      }
      else if ( type == QVariant::Double )
      {
        // binding a DOUBLE value
        query.addBindValue( it2->toDouble() );
      }
      else if ( type == QVariant::String )
      {
        // binding a TEXT value
        query.addBindValue( it2->toString() );
      }
      else if ( type == QVariant::DateTime )
      {
//.........这里部分代码省略.........