使用 pos_hint 定位小部件(例如 Scatter)后，如何获取当前的 x、y 位置 (pos)？
例如
wid.pos = (250, 350)
print wid.pos <----- # it print (200, 350). Correct.
wid.pos_hint = {'top':0.9, 'right':0.5} # moved the widget to other position using pos_hint.
print wid.pos <----- # it sill print (200, 350) eventhough the widget position has changed.
编辑:示例代码
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.scatter import Scatter
Builder.load_string("""
<Icon@Scatter>:
size_hint: .06, .08
Image:
size: root.size
allow_stretch: True
keep_ratio: True
""")
class Icon(Scatter):
def __init__(self, **kwargs):
self.pos = (200, 200)
self.move()
super(Icon, self).__init__(**kwargs)
def move(self):
print "BEFORE: "
print self.pos # print 200, 200
self.pos_hint = {'top':0.9, 'right':0.5} # assume now Scatter has moved to x800 y500.
print "AFTER: "
print self.pos # it still print 200, 200 :(
class GameApp(App):
def build(self):
return Icon()
if __name__ == '__main__':
GameApp().run()
请您参考如下方法:
问题是窗口(和布局本身)在分配布局支持的值(如 size_hint 或 pos_hint)后不会立即刷新。它们在窗口刷新后立即更新(直到方法结束)
你基本上可以调用方法do_layout明确地。文档说“当需要布局时，触发器会调用此方法”。我不得不说我不确定显式调用它是否会导致一些问题，因为没有记录这种用法。它对我有用，但要小心:
wid.pos = (250, 350)
print wid.pos # it prints (200, 350). Correct.
wid.pos_hint = {'top':0.9, 'right':0.5}
print wid.pos # it sill print (200, 350)
wid.do_layout()
print wid.pos # it should work now
当您让窗口刷新时，即在您实际看到 Scatter(或任何其他 Widget)已经移动之后，这不是必需的。
编辑:问题中代码的更正版本
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.scatter import Scatter
from kivy.uix.floatlayout import FloatLayout
Builder.load_string("""
<Icon>:
size_hint: .06, .08
Image:
size: root.size
allow_stretch: True
keep_ratio: True
<BaseLayout>:
icon: _icon
Icon:
id: _icon
Button:
text: "Press me"
size_hint: .1,.05
on_press: _icon.move()
""")
class Icon(Scatter):
def __init__(self, **kwargs):
self.pos = (200, 200)
super(Icon, self).__init__(**kwargs)
def move(self):
print "BEFORE: "
print self.pos # print 200, 200
self.pos_hint = {'top':0.9, 'right':0.5} # assume now Scatter has moved to x800 y500.
self.parent.do_layout()
print "AFTER: "
print self.pos # it still print 200, 200 :(
class BaseLayout(FloatLayout):
pass
class GameApp(App):
def build(self):
return BaseLayout()
if __name__ == '__m
ain__':
GameApp().run()
