'''
Float Layout
============
:class:`FloatLayout` honors the :attr:`~kivy.uix.widget.Widget.pos_hint`
and the :attr:`~kivy.uix.widget.Widget.size_hint` properties of its children.
.. only:: html
.. image:: images/floatlayout.gif
:align: right
.. only:: latex
.. image:: images/floatlayout.png
:align: right
For example, a FloatLayout with a size of (300, 300) is created::
layout = FloatLayout(size=(300, 300))
By default, all widgets have their size_hint=(1, 1), so this button will adopt
the same size as the layout::
button = Button(text='Hello world')
layout.add_widget(button)
To create a button 50% of the width and 25% of the height of the layout and
positioned at (20, 20), you can do::
button = Button(
text='Hello world',
size_hint=(.5, .25),
pos=(20, 20))
If you want to create a button that will always be the size of layout minus
20% on each side::
button = Button(text='Hello world', size_hint=(.6, .6),
pos_hint={'x':.2, 'y':.2})
.. note::
This layout can be used for an application. Most of the time, you will
use the size of Window.
.. warning::
If you are not using pos_hint, you must handle the positioning of the
children: if the float layout is moving, you must handle moving the
children too.
'''
__all__ = ('FloatLayout', )
from kivy.uix.layout import Layout
[docs]class FloatLayout(Layout):
'''Float layout class. See module documentation for more information.
'''
def __init__(self, **kwargs):
super(FloatLayout, self).__init__(**kwargs)
fbind = self.fbind
update = self._trigger_layout
fbind('children', update)
fbind('pos', update)
fbind('pos_hint', update)
fbind('size_hint', update)
fbind('size', update)
[docs] def do_layout(self, *largs, **kwargs):
# optimize layout by preventing looking at the same attribute in a loop
w, h = kwargs.get('size', self.size)
x, y = kwargs.get('pos', self.pos)
for c in self.children:
# size
shw, shh = c.size_hint
shw_min, shh_min = c.size_hint_min
shw_max, shh_max = c.size_hint_max
if shw is not None and shh is not None:
c_w = shw * w
c_h = shh * h
if shw_min is not None and c_w < shw_min:
c_w = shw_min
elif shw_max is not None and c_w > shw_max:
c_w = shw_max
if shh_min is not None and c_h < shh_min:
c_h = shh_min
elif shh_max is not None and c_h > shh_max:
c_h = shh_max
c.size = c_w, c_h
elif shw is not None:
c_w = shw * w
if shw_min is not None and c_w < shw_min:
c_w = shw_min
elif shw_max is not None and c_w > shw_max:
c_w = shw_max
c.width = c_w
elif shh is not None:
c_h = shh * h
if shh_min is not None and c_h < shh_min:
c_h = shh_min
elif shh_max is not None and c_h > shh_max:
c_h = shh_max
c.height = c_h
# pos
for key, value in c.pos_hint.items():
if key == 'x':
c.x = x + value * w
elif key == 'right':
c.right = x + value * w
elif key == 'pos':
c.pos = x + value[0] * w, y + value[1] * h
elif key == 'y':
c.y = y + value * h
elif key == 'top':
c.top = y + value * h
elif key == 'center':
c.center = x + value[0] * w, y + value[1] * h
elif key == 'center_x':
c.center_x = x + value * w
elif key == 'center_y':
c.center_y = y + value * h
