Chained Attribute Alias Example

An example of using chained Enaml aliases.

This example is functionally equivalent to ‘chained_widget_alias.enaml’, but it shows how the developer can exert more control over a widget by exposing individual attributes instead of entire widgets.

Tip

To see this example in action, download it from chained_attribute_alias and run:

$ enaml-run chained_attribute_alias.enaml

Screenshot

Example Enaml Code

#------------------------------------------------------------------------------
# Copyright (c) 2013, Nucleic Development Team.
#
# Distributed under the terms of the Modified BSD License.
#
# The full license is in the file LICENSE, distributed with this software.
#------------------------------------------------------------------------------
""" An example of using chained Enaml aliases.

This example is functionally equivalent to 'chained_widget_alias.enaml',
but it shows how the developer can exert more control over a widget by
exposing individual attributes instead of entire widgets.

<< autodoc-me >>
"""
from enaml.widgets.api import Window, Container, Slider, Field, GroupBox


enamldef InternalBox(GroupBox):
    """ The internal content box.

    The slider is aliased via 'slider'.

    """
    alias slider
    title = 'Inner Box'
    Slider: slider:
        pass


enamldef OuterBox(GroupBox):
    """ The outer content box.

    The internal slider value is aliased via 'slider_value'.

    """
    alias slider_value: internal.slider.value
    title = 'Outer Box'
    InternalBox: internal:
        pass


enamldef Main(Window):
    """ The main application window.

    This window uses a chained alias to bind the inner slider of the
    group boxes to the other slider in the main window. It also uses
    a subscription on the chained alias to update a read only field.

    """
    title = 'Chained Attribute Alias'
    Container:
        OuterBox: outer:
            slider_value := slider.value
        Slider: slider:
            value = 50
        Field:
            read_only = True
            text << str(outer.slider_value)