Python rk（我也是matham）。太棒了。再次感谢您的回复！感谢您花时间阅读本文，并在@matt提供如此详细的回复。你的解决方案非常有效。我将详细阅读ids的使用，因为我以前从未见过。因此，版主们，不确定在回复中提出额外问题的政策，因此，如果我应该发布一个新问题

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rk（我也是matham）。太棒了。再次感谢您的回复！感谢您花时间阅读本文，并在@matt提供如此详细的回复。你的解决方案非常有效。我将详细阅读

ids

的使用，因为我以前从未见过。因此，版主们，不确定在回复中提出额外问题的政策，因此，如果我应该发布一个新问题，他们表示歉意@matt有没有一种简单的方法可以从KivyPlayer类的init方法中选择第一个/下一个节点？很高兴在kivy IRC中讨论你是否有手柄？我发现了一种黑客方法，即使用ButtonBehavior类和trigger动作方法

self.next\u track.trigger动作（duration=0.1）

我怀疑有一种更干净的方法：）你确实需要使用时钟来实现这一点。但是类似于

Clock.schedule\u once（lambda*x:self.ids.controller.select\u node（0），0.1）

。但是你应该在IRC上询问它是否起作用（我也是那里的matham）。太棒了。再次感谢您的回复！

# -*- coding: utf-8 -*-
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.recycleview import RecycleView
from kivy.uix.recycleview.views import RecycleDataViewBehavior
from kivy.uix.label import Label
from kivy.properties import BooleanProperty, StringProperty, NumericProperty 
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: (0.4, 0.4, 0.4, 1) if self.selected else (0.5, 0.5, 0.5, 1)
        Rectangle:
            pos: self.pos
            size: self.size

<KivyPlayer>:
    canvas:
        Color:
            rgba: 0.3, 0.3, 0.3, 1
        Rectangle:
            size: self.size
            pos: self.pos
    orientation: 'vertical'
    BoxLayout:  
        orientation: 'vertical'
        BoxLayout:
            Button:
                id: next_track
                text: "Next Track"
            Button:
                id: previous_track
                text: "Previous Track"
        BoxLayout:
            RecycleView:
                id: media_list
                viewclass: 'SelectableLabel'
                scroll_type: ['bars', 'content']
                scroll_wheel_distance: dp(114)
                bar_width: dp(10)
                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
                    spacing: dp(2)


"""

Builder.load_string(kv)

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, index, 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, rv, index, 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 KivyPlayer(BoxLayout):
    ''' Main Kivy class for creating the initial BoxLayout '''

    def __init__(self, **kwargs):
        super(KivyPlayer, self).__init__(**kwargs)

       # Set media_list data
        self.ids.media_list.data = [{'text': str(x)} for x in range(100)]


class KivyApp(App):
    def build(self):
        return KivyPlayer()


if __name__ == '__main__':
    KivyApp().run()

BoxLayout:
    Button:
        id: next_track
        text: "Next Track"
        on_release: controller.select_next()
    Button:
        id: previous_track
        text: "Previous Track"
        on_release: controller.select_previous()

SelectableRecycleBoxLayout:
    id: controller
    key_selection: 'selectable'

class SelectableRecycleBoxLayout(FocusBehavior, LayoutSelectionBehavior,
                                 RecycleBoxLayout):
    ''' Adds selection and focus behaviour to the view. '''

    def get_nodes(self):
        nodes = self.get_selectable_nodes()
        if self.nodes_order_reversed:
            nodes = nodes[::-1]
        if not nodes:
            return None, None

        selected = self.selected_nodes
        if not selected:  # nothing selected, select the first
            self.select_node(nodes[0])
            return None, None

        if len(nodes) == 1:  # the only selectable node is selected already
            return None, None

        last = nodes.index(selected[-1])
        self.clear_selection()
        return last, nodes

    def select_next(self):
        last, nodes = self.get_nodes()
        if not nodes:
            return

        if last == len(nodes) - 1:
            self.select_node(nodes[0])
        else:
            self.select_node(nodes[last + 1])

    def select_previous(self):
        last, nodes = self.get_nodes()
        if not nodes:
            return

        if not last:
            self.select_node(nodes[-1])
        else:
            self.select_node(nodes[last - 1])