问题描述
我到处搜索过，但找不到如何在Kivy中更新RecycleView对象的数据。我从文档中获取了示例，添加了一个按钮，并想将列表中的第一个变量从1更改为101。
我已阅读到，一旦更改了数据，更新链接到recycleview的数据应自动刷新视图，但事实并非如此。我尝试在应用程序类中创建ListProperty变量并进行更改，但不幸的是，该方法也不起作用。
下面是我的代码：
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.recycleview import RecycleView
from kivy.uix.recycleview.views import RecycleDataViewBehavior
from kivy.uix.label import Label
from kivy.properties import BooleanProperty,ListProperty
from kivy.uix.recycleBoxlayout import RecycleBoxLayout
from kivy.uix.behaviors import FocusBehavior
from kivy.uix.recycleview.layout import LayoutSelectionBehavior
kv = ('''
<SelectableLabel>:
# Draw a background to indicate selection
canvas.before:
Color:
rgba: (.0,0.9,.1,.3) if self.selected else (0,1)
Rectangle:
pos: self.pos
size: self.size
<RV>:
id: rv
viewclass: 'SelectableLabel'
SelectableRecycleBoxLayout:
default_size: None,dp(56)
default_size_hint: 1,None
size_hint_y: None
height: self.minimum_height
orientation: 'vertical'
multiselect: True
touch_multiselect: True
Screen:
BoxLayout:
Button:
text:'Change the RecycleView Data'
on_release:
print('Want to change the data here')
root.ids.rv.change_line()
RV:
''')
class SelectableRecycleBoxLayout(FocusBehavior,LayoutSelectionBehavior,RecycleBoxLayout):
''' Adds selection and focus behavIoUr to the view. '''
class SelectableLabel(RecycleDataViewBehavior,Label):
''' Add selection support to the Label '''
index = None
selected = BooleanProperty(False)
selectable = BooleanProperty(True)
def refresh_view_attrs(self,rv,index,data):
''' Catch and handle the view changes '''
self.index = index
return super(SelectableLabel,self).refresh_view_attrs(
rv,data)
def on_touch_down(self,touch):
''' Add selection on touch down '''
if super(SelectableLabel,self).on_touch_down(touch):
return True
if self.collide_point(*touch.pos) and self.selectable:
return self.parent.select_with_touch(self.index,touch)
def apply_selection(self,is_selected):
''' Respond to the selection of items in the view. '''
self.selected = is_selected
if is_selected:
print("selection changed to {0}".format(rv.data[index]))
else:
print("selection removed for {0}".format(rv.data[index]))
class RV(RecycleView):
def __init__(self,**kwargs):
super(RV,self).__init__(**kwargs)
self.data = [{'text': str(x)} for x in range(100)]
def change_line(self):
self.data[0] = '101'
class TestApp(App):
data = ListProperty
def build(self):
self.root_widget = Builder.load_string(kv)
return self.root_widget
if __name__ == '__main__':
TestApp().run()
解决方法
您应该将ID放在根对象中。那会使id被root识别。 而且您不需要调用“ root.ids”。在kv中调用ID时。
kv = ('''
<SelectableLabel>:
# Draw a background to indicate selection
canvas.before:
Color:
rgba: (.0,0.9,.1,.3) if self.selected else (0,1)
Rectangle:
pos: self.pos
size: self.size
<RV>:
viewclass: 'SelectableLabel'
SelectableRecycleBoxLayout:
default_size: None,dp(56)
default_size_hint: 1,None
size_hint_y: None
height: self.minimum_height
orientation: 'vertical'
multiselect: True
touch_multiselect: True
Screen:
BoxLayout:
Button:
text:'Change the RecycleView Data'
on_release:
print('Want to change the data here')
rv.change_line() #<--- call the id inside kv
RV:
id: rv
''')
...
self.root_widget = Builder.load_string(kv)
self.root_widget.ids['rv'] #<---- calling the id within python script
完整代码：
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.recycleview import RecycleView
from kivy.uix.recycleview.views import RecycleDataViewBehavior
from kivy.uix.label import Label
from kivy.properties import BooleanProperty,ListProperty
from kivy.uix.recycleboxlayout import RecycleBoxLayout
from kivy.uix.behaviors import FocusBehavior
from kivy.uix.recycleview.layout import LayoutSelectionBehavior
kv = ('''
<SelectableLabel>:
# Draw a background to indicate selection
canvas.before:
Color:
rgba: (.0,None
size_hint_y: None
height: self.minimum_height
orientation: 'vertical'
multiselect: True
touch_multiselect: True
Screen:
BoxLayout:
Button:
text:'Change the RecycleView Data'
on_release:
print('Want to change the data here')
rv.change_line()
RV:
id: rv
''')
class SelectableRecycleBoxLayout(FocusBehavior,LayoutSelectionBehavior,RecycleBoxLayout):
''' Adds selection and focus behaviour to the view. '''
class SelectableLabel(RecycleDataViewBehavior,Label):
''' Add selection support to the Label '''
index = None
selected = BooleanProperty(False)
selectable = BooleanProperty(True)
def refresh_view_attrs(self,rv,index,data):
''' Catch and handle the view changes '''
self.index = index
return super(SelectableLabel,self).refresh_view_attrs(
rv,data)
def on_touch_down(self,touch):
''' Add selection on touch down '''
if super(SelectableLabel,self).on_touch_down(touch):
return True
if self.collide_point(*touch.pos) and self.selectable:
return self.parent.select_with_touch(self.index,touch)
def apply_selection(self,is_selected):
''' Respond to the selection of items in the view. '''
self.selected = is_selected
if is_selected:
print("selection changed to {0}".format(rv.data[index]))
else:
print("selection removed for {0}".format(rv.data[index]))
class RV(RecycleView):
def __init__(self,**kwargs):
super(RV,self).__init__(**kwargs)
self.data = [{'text': str(x)} for x in range(100)]
def change_line(self):
self.data[0] = '101'
class TestApp(App):
data = ListProperty
def build(self):
self.root_widget = Builder.load_string(kv)
return self.root_widget
if __name__ == '__main__':
TestApp().run()