Source code for qct_interfaces.attributeviews

"""
The definition of the IAttributeView interface.
"""
#
# Copyright Qualcomm Technologies Inc, 2019.
# All Rights Reserved
#

# Python imports

# Thirdparty imports
from zope.interface import Interface, Attribute

# Zope interface bends the rules slightly, so ignore these pylint warnings:
# pylint: disable=no-self-argument,inherit-non-class,no-method-argument


class IAttributeView(Interface):
    """This adapter defines the interface to a view object that creates
    and manages the widgets that display and edit the attribute which
    are contained in a ConfigContainer.

    The code that creates instances of this interface is done by
    runnng something like this::

        from qct_interfaces import make_registered_named_instance
        from qct_interfaces.attributeviews import IAttributeView
        ...
        check_box_view = make_registered_named_instance(IAttributeView,
                                                        'view:qtcheckbox',
                                                        config_attribute=attr)
        check_box_view.create()


    Note the use of the ``name`` in this call. The container
    implementation will look for the attribute view using the most
    specific to the least specific binding. This means that the code
    will look for an IAttributeView implmentation registered with the
    name::

            'item:' + attr.attr_key

    first (e.g. ``item:bluetooth_disable_role_switching``), and if
    that doesn't exist then::

            'class:' + attr.attr_type

    next (e.g. ``class:bool``), and then finally with the view name
    defined in the attribute::

            'view:' + attr.attr_view

    (e.g. ``view:qtcheckbox``).

    Plugins can choose to implement their own version of these
    implementations at whatever level they need to, and so change the
    presentation layer of the user interface.
    """

    config_attribute = Attribute("""The ConfigDomain attribute which the widget
                                 should be editing.""")

    self_labelled = Attribute("""Boolean value to indicate whether the view
                              contructs its own label.""")

    widget = Attribute("""The top-level widget of this view. It is only valid
                       after the ``create`` method is called.""")

    def create() -> None:
        """This method should construct the widget(s) required for displaying
        the attribute, which can be accessed by the ``widget``
        attribute. The caller can then add the widget to the layout of
        the panel.
        """

    def update() -> None:
        """This method updates the enabled state of the widget(s) associated
        with the view. This method gets called on all visible
        attributes whenever one of them is changed.
        """