Kivy:如何在等待显示另一个小部件时显示一个小部件(都从同一个事件调用)

2022-01-15 00:00:00 python kivy widget

问题描述

单击确定按钮"时，我的 kivy 应用程序检索有时包含 100 多个文件夹的列表，并显示每个文件夹 4 列和 1 行的 GridLayout.每行有 3 个可滚动标签和 1 个复选框.这个 GridLayout 有时需要将近 12 秒才能生成，所以我想同时显示一些东西(标签、图像......).

When an "OK button" is clicking, my kivy app retrieves a list of sometimes 100+ folders and displays a GridLayout with 4 columns and 1 row per folder. Each row has 3 scrollable labels and 1 checkbox. This GridLayout sometimes takes close to 12 sec to be generated so I would like to display something (a label, an image...) in the meantime.

尝试 1: 我的确定按钮"调用 def DisplayTable.我试图简单地在 DisplayTable 的开头添加 self.add_widget(Label_when_waiting) (所以在任何处理或生成 GridLayout 之前)但 Label_when_waiting 仅在 GridLayout 时显示显示.

Attempt 1: My "Ok button" calls a def DisplayTable. I tried to simply add self.add_widget(Label_when_waiting) right at the beginning of DisplayTable (so before any processing or generating the GridLayout) but the Label_when_waiting is displayed only when GridLayout is displayed.

尝试2:我试图将def DisplayTable分成两个def，Diplay_Label_when_waiting(由确定按钮"调用的那个)和DisplayTable:

Attempt 2: I tried to separate def DisplayTable into two def, Diplay_Label_when_waiting(the one called by the "OK button") and DisplayTable:

def Diplay_Label_when_waiting(self, *args):
    self.add_widget(Label_when_waiting)
    DisplayTable(self, *args)

但这里又是 Label_when_waiting 仅在显示 GridLayout 时才显示.

But here again, Label_when_waiting is displayed only when GridLayout is displayed.

那么我如何在 GridLayout 之前显示 Label_when_waiting 知道两个显示都必须由确定按钮"触发

So how can I display Label_when_waiting before GridLayout knowing that both displays have to be triggered by the "Ok button"

解决方案

使用Clock.schedule_once在标签显示后显示Grid:

Use Clock.schedule_once to display the Grid after the label is shown:

def Diplay_Label_when_waiting(self, *args):
    self.add_widget(Label_when_waiting)
    Clock.schedule_once(lambda dt: DisplayTable(self, *args), 0)

您也可以使用 kivyoav 中的 delayable(免责声明 - 我是作者...)

You can also use delayable from kivyoav (DISCLAIMER - I'm the author ...)

from kivyoav.delayed import delayable

@delayable
def Diplay_Label_when_waiting(self, *args):
    self.add_widget(Label_when_waiting)
    yield 0.0 # delay of 0ms , will cause the UI to update...
    DisplayTable(self, *args)

相关文章