Source code for enaml.widgets.flow_area

#  Copyright (c) 2012, Enthought, Inc.
#  All rights reserved.
from traits.api import Enum, Range, Property, cached_property

from enaml.core.trait_types import CoercingInstance
from enaml.layout.geometry import Box

from .constraints_widget import ConstraintsWidget
from .flow_item import FlowItem

[docs]class FlowArea(ConstraintsWidget): """ A widget which lays out its children in flowing manner, wrapping around at the end of the available space. """ #: The flow direction of the layout. direction = Enum( 'left_to_right', 'right_to_left', 'top_to_bottom', 'bottom_to_top' ) #: The alignment of a line of items within the layout. align = Enum('leading', 'trailing', 'center', 'justify') #: The amount of horizontal space to place between items. horizontal_spacing = Range(low=0, value=10) #: The amount of vertical space to place between items. vertical_spacing = Range(low=0, value=10) #: The margins to use around the outside of the flow area. margins = CoercingInstance(Box, (10, 10, 10, 10)) #: A read only property which returns the area's flow items. flow_items = Property(depends_on='children') #: A FlowArea expands freely in width and height by default. hug_width = 'ignore' hug_height = 'ignore' #-------------------------------------------------------------------------- # Initialization #--------------------------------------------------------------------------
[docs] def snapshot(self): """ Returns the snapshot dict for the FlowArea. """ snap = super(FlowArea, self).snapshot() snap['direction'] = self.direction snap['align'] = self.align snap['horizontal_spacing'] = self.horizontal_spacing snap['vertical_spacing'] = self.vertical_spacing snap['margins'] = self.margins return snap
[docs] def bind(self): """ Bind the change handler for the FlowItem. """ super(FlowArea, self).bind() attrs = ( 'direction', 'align', 'horizontal_spacing','vertical_spacing', 'margins', ) self.publish_attributes(*attrs) #-------------------------------------------------------------------------- # Private API #--------------------------------------------------------------------------
@cached_property def _get_flow_items(self): """ The getter for the 'flow_items' property. Returns ------- result : tuple The tuple of FlowItem children defined for this area. """ isinst = isinstance items = (c for c in self.children if isinst(c, FlowItem)) return tuple(items)