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重置Kivy中的可选择标签

kivy

Zu Jiry · 技术社区 · 7 年前

ScreenTest是一个屏幕,包含:
-具有可选标签的视图
-根据所选标签更改的标签
-复位按钮

重置按钮应该重置视图中所做的选择,但我不知道如何将所选的可选择标签设置为false。我无法访问任何ID或类来更改此参数
我需要的是,通过单击“重置”按钮,视图中没有选择任何内容,因此标签中不会显示任何文本(或文本重置为“”,因为所选文本为空)。

from kivy.app import App
from kivy.lang import Builder
from kivy.properties import BooleanProperty
from kivy.uix.behaviors import FocusBehavior
from kivy.uix.label import Label
from kivy.uix.recycleboxlayout import RecycleBoxLayout
from kivy.uix.recycleview import RecycleView
from kivy.uix.recycleview.layout import LayoutSelectionBehavior
from kivy.uix.recycleview.views import RecycleDataViewBehavior
from kivy.uix.screenmanager import ScreenManager, Screen

Builder.load_string("""

<ScreenTest>:
    BoxLayout:
        TestView:
            id: test_view

        Label:
            id: text_lbl
            text: "" if not test_view.text_selected else test_view.text_selected 


        Button:
            id: reset_btn
            on_press: print("Wow")


<TestView>:
    viewclass: 'SelectableLabel'
    text_selected: ''
    name_selected: ''

    SelectableRecycleBoxLayout:
        id: culture_sub_view_layout
        orientation: 'vertical'
        default_size: None, dp(32)
        default_size_hint: .6, None
        size_hint: 1, .9
        multiselect: False
        touch_multiselect: False


<SelectableLabel>:
    # Draw a background to indicate selection
    canvas.before:
        Color:
            rgba: (.05, 0.5, .9, .8) if self.selected else (.5, .5, .5, 1)
        Rectangle:
            pos: self.pos
            size: self.size
""")


class TestView(RecycleView):
    def __init__(self, **kwargs):
        super(TestView, self).__init__(**kwargs)
        self.data =  [
            {"text": "Test1", "description": "Test1.text"},
            {"text": "Test2", "description": "Test2.text"},
            {"text": "Test3", "description": "Test3.text"}
        ]


class SelectableRecycleBoxLayout(FocusBehavior, LayoutSelectionBehavior,
                                 RecycleBoxLayout):
    pass


class SelectableLabel(RecycleDataViewBehavior, Label):
    index = None
    selected = BooleanProperty(False)
    selectable = BooleanProperty(True)

    def refresh_view_attrs(self, rv, index, data):
        self.index = index
        return super(SelectableLabel, self).refresh_view_attrs(
            rv, index, data)

    def on_touch_down(self, touch):
        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, rv, index, is_selected):
        self.selected = is_selected
        if is_selected:
            print("selection changed to {0}".format(rv.data[index]))
            rv.name_selected = rv.data[index]['text']
            rv.text_selected = rv.data[index]['description']
        else:
            print("selection removed for {0}".format(rv.data[index]))


class ScreenTest(Screen):
    pass


sm = ScreenManager()
sm.add_widget(ScreenTest(name='menu'))


class TestApp(App):
    def build(self):
        return sm


test_app = TestApp()
test_app.run()

谢谢!

1 回复 | 直到 7 年前

Kacperito 7 年前

快速解决方案

我相信最简单的方法是遍历回收框中的元素,如果选择了它们,则取消选择,并将文本设置为 "" . 考虑在 TestView 班级:

def remove_selection(self):
    # Remove text
    self.parent.children[1].text = ""

    # Remove selection
    for child in self.children[0].children:
        if child.selected:
            child.selected = False

当然,您必须在按下按钮时调用它,您可以将布局更改为:

Button:
    id: reset_btn
    on_press: test_view.remove_selection()

稍微好一点的方法

打给孩子和家长的电话可能会在更复杂的布局中变得相当混乱,所以我想建议一种更干净的方法来解决您的问题。由于一次只处理一个选定的项,我认为最好的方法是将项本身存储在程序中,并在需要时从中检索信息。准确地说,不是储存 name_selected 和 text_selected 在你的 test_view ,您只需存储所选项目。为此,必须引入一些更改:

进口 ObjectProperty 和 StringProperty :

from kivy.properties import BooleanProperty, ObjectProperty, StringProperty

增加一个 selected 归因于 测试视图 类,允许 None 有助于检查是否选择了任何内容:
```
class TestView(RecycleView):
    selected = ObjectProperty(None, allownone=True)
```

编辑 remove_selection 我上面提到的方法:

def remove_selection(self):
    # Remove selection
    if self.selected is not None:
        self.selected.selected = False
        self.selected = None

添加 选定的文本 和 已选择姓名 属性到 SelectableLabel 班级:

class SelectableLabel(RecycleDataViewBehavior, Label):
    index = None
    selected = BooleanProperty(False)
    selectable = BooleanProperty(True)
    text_selected = StringProperty()
    name_selected = StringProperty()

编辑 apply_selection 方法:

def apply_selection(self, rv, index, is_selected):
    self.selected = is_selected
    if is_selected:
        print("selection changed to {0}".format(rv.data[index]))
        # Store selected text and name inside the label
        self.name_selected = rv.data[index]['text']
        self.text_selected = rv.data[index]['description']
        # Remember the selection
        rv.selected = self
    else:
        print("selection removed for {0}".format(rv.data[index]))

更改显示在 text_lbl :

Label:
    id: text_lbl
    text: "" if test_view.selected is None else test_view.selected.text_selected

删除不需要的属性( 选定的文本 , 已选择姓名 从 <TestView> :
```
<TestView>:
    viewclass: 'SelectableLabel'
```