def filterAcceptsRow(self, source_row, source_parent):
        """The filter method

        .. note:: This filter hides top-level items of unsupported branches
                  and also leaf items containing xml files.

           Enabled root items: QgsDirectoryItem, QgsFavouritesItem,
           QgsPGRootItem.

           Disabled root items: QgsMssqlRootItem, QgsSLRootItem,
           QgsOWSRootItem, QgsWCSRootItem, QgsWFSRootItem, QgsWMSRootItem.

           Disabled leaf items: QgsLayerItem and QgsOgrLayerItem with path
           ending with '.xml'

        :param source_row: Parent widget of the model
        :type source_row: int

        :param source_parent: Parent item index
        :type source_parent: QModelIndex

        :returns: Item validation result
        :rtype: bool
        """
        source_index = self.sourceModel().index(source_row, 0, source_parent)
        item = self.sourceModel().dataItem(source_index)

        if item.metaObject().className() not in [
                'QgsPGRootItem',
                'QgsPGConnectionItem',
                'QgsPGSchemaItem',
                'QgsPGLayerItem',
                'QgsFavoritesItem',
                'QgsDirectoryItem',
                'QgsLayerItem',
                'QgsGdalLayerItem',
                'QgsOgrLayerItem']:
            return False

        if item.path().endswith('.xml'):
            return False

        return True
The filter method

        .. note:: This filter hides top-level items of unsupported branches
                  and also leaf items containing xml files.

           Enabled root items: QgsDirectoryItem, QgsFavouritesItem,
           QgsPGRootItem.

           Disabled root items: QgsMssqlRootItem, QgsSLRootItem,
           QgsOWSRootItem, QgsWCSRootItem, QgsWFSRootItem, QgsWMSRootItem.

           Disabled leaf items: QgsLayerItem and QgsOgrLayerItem with path
           ending with '.xml'

        :param source_row: Parent widget of the model
        :type source_row: int

        :param source_parent: Parent item index
        :type source_parent: QModelIndex

        :returns: Item validation result
        :rtype: bool