#------------------------------------------------------------------------------
# Copyright (c) 2005, Enthought, Inc.
# All rights reserved.
# 
# This software is provided without warranty under the terms of the BSD
# license included in enthought/LICENSE.txt and may be redistributed only
# under the conditions described in the aforementioned license.  The license
# is also available online at http://www.enthought.com/licenses/BSD.txt
# Thanks for using Enthought open source!
# 
# Author: Enthought, Inc.
# Description: <Enthought pyface package component>
#------------------------------------------------------------------------------
""" Base class for all column providers. """


# Enthought library imports.
from enthought.traits.api import HasTraits, Int


class ColumnProvider(HasTraits):
    """ Base class for all column providers. 

    By default a column's label is 'Column n' and is 100 pixels wide.

    """

    # The number of columns.
    column_count = Int

    ###########################################################################
    # 'TableColumnProvider' interface.
    ###########################################################################

    def get_label(self, viewer, column_index):
        """ Returns the label for a column. """

        return 'Column %d' % column_index

    def get_width(self, viewer, column_index):
        """ Returns the width of a column.

        Returning -1 (the default) means that the column will be sized to
        fit its longest item (or its column header if it is longer than any
        item).

        """

        return -1

    def get_alignment(self, viewer, column_index):
        """ Returns the alignment of the column header and cells.

        Returns, 'left', 'right', 'centre' or 'center' ('left' by default).

        """

        return 'left'
        
#### EOF ######################################################################
