Source code for pyface.i_layout_item

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from traits.api import Enum, Int, Interface, Tuple

#: Value that indicates the default size values should be used.
DEFAULT_SIZE = -1

#: Trait for sizes of widgets.
Size = Tuple(Int(DEFAULT_SIZE), Int(DEFAULT_SIZE))

#: Trait for size policy values.
SizePolicy = Enum("default", "fixed", "preferred", "expand")


class ILayoutItem(Interface):
    """ An item that can participate in layout. """

    #: The minimum size that the item can take.
    minimum_size = Size

    #: The maximum size that the item can take.
    maximum_size = Size

    #: Weight factor used to distribute extra space between widgets.
    stretch = Tuple(Int, Int)

    #: How the item should behave when more space is available.
    size_policy = Tuple(SizePolicy, SizePolicy)