Python Kivy ListView: How to delete selected ListItemButton?

问题

I'm trying to learn kivy by building a simple todo-list app like suggested by Dusty Phillips, author of the book "Creating apps in Kivy".

This is the code so far:

from kivy.app import App
from kivy.uix.boxlayout import BoxLayout
from kivy.properties import ObjectProperty
from kivy.uix.listview import ListItemButton


class TaskButton(ListItemButton):
    pass


class TodoRoot(BoxLayout):
    task_input = ObjectProperty()
    task_list = ObjectProperty()

    def add_task(self):
        self.task_list.adapter.data.extend([self.task_input.text])
        self.task_list._trigger_reset_populate()

    def del_task(self):
        pass


class TodoApp(App):
    def build(self):
        return TodoRoot()


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

And this is the kv file:

#: import main todo
#: import ListAdapter kivy.adapters.listadapter.ListAdapter
#: import ListItemButton kivy.uix.listview.ListItemButton

TodoRoot:

<TodoRoot>:
    orientation: "vertical"
    task_input: task_input_view
    task_list: tasks_list_view

    BoxLayout:
        size_hint_y: None
        height: "40dp"

        TextInput:
            id: task_input_view
            size_hint_x: 70
        Button:
            text: "Add"
            size_hint_x: 15
            on_press: root.add_task()
        Button:
            text: "Del"
            size_hint_x: 15
            on_press: root.del_task()
    ListView:
        id: tasks_list_view
        adapter:
            ListAdapter(data=[], cls=main.TaskButton)

This is what it looks like:

I know the ListView API is still somewhat experimental and I'm complaining about the examples on using adapters / converters, google & SO search didn't help either. So what code is needed to make the Del-Button work and remove a selected ListItemButton?

回答1:

After a lot of reading ListView API docs & examples, I finally found out myself. What we need is the selection-Property of the listadapter-Class, then we can simply call the inherited remove method of the adapter.data-ListProperty.

So for anyone interesested this is the code:

def del_task(self, *args):
    if self.task_list.adapter.selection:
        selection = self.task_list.adapter.selection[0].text
        self.task_list.adapter.data.remove(selection)
        self.task_list._trigger_reset_populate()

来源：https://stackoverflow.com/questions/25981827/python-kivy-listview-how-to-delete-selected-listitembutton

标签

python

listview

kivy