#------------------------------------------------------------------------------
# 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.
#------------------------------------------------------------------------------
from atom.api import Enum, Range, Coerced, Typed, ForwardTyped, set_default
from enaml.core.declarative import d_, observe
from enaml.layout.geometry import Box
from .frame import Frame, ProxyFrame, Border
from .flow_item import FlowItem
class ProxyFlowArea(ProxyFrame):
""" The abstract definition of a proxy FlowArea object.
"""
#: A reference to the FlowArea declaration.
declaration = ForwardTyped(lambda: FlowArea)
def set_direction(self, direction):
raise NotImplementedError
def set_align(self, align):
raise NotImplementedError
def set_horizontal_spacing(self, spacing):
raise NotImplementedError
def set_vertical_spacing(self, spacing):
raise NotImplementedError
def set_margins(self, margins):
raise NotImplementedError
[docs]
class FlowArea(Frame):
""" 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 = d_(Enum(
'left_to_right', 'right_to_left', 'top_to_bottom', 'bottom_to_top'
))
#: The alignment of a line of items within the layout.
align = d_(Enum('leading', 'trailing', 'center', 'justify'))
#: The amount of horizontal space to place between items.
horizontal_spacing = d_(Range(low=0, value=10))
#: The amount of vertical space to place between items.
vertical_spacing = d_(Range(low=0, value=10))
#: The margins to use around the outside of the flow area.
margins = d_(Coerced(Box, (10, 10, 10, 10)))
#: A FlowArea expands freely in width and height by default.
hug_width = set_default('ignore')
hug_height = set_default('ignore')
#: A reference to the ProxyFlowArea object.
proxy = Typed(ProxyFlowArea)
[docs]
def flow_items(self):
""" Get the flow item children defined on this area.
"""
return [c for c in self.children if isinstance(c, FlowItem)]
#--------------------------------------------------------------------------
# Default Handlers
#--------------------------------------------------------------------------
def _default_border(self):
""" Get the default border for the flow area.
The default value matches the default for Qt's QScrollArea.
"""
return Border(style='styled_panel', line_style='sunken')
#--------------------------------------------------------------------------
# Observers
#--------------------------------------------------------------------------
@observe('direction', 'align', 'horizontal_spacing', 'vertical_spacing',
'margins')
def _update_proxy(self, change):
""" An observer which sends state change to the proxy.
"""
# The superclass handler implementation is sufficient.
super(FlowArea, self)._update_proxy(change)