問題描述

我想創建多個按鈕并將它們綁定到一個函數.問題是，每當我單擊一個按鈕時，都會多次調用該函數.似乎是事件連接的問題.當我查看按下按鈕時調用該函數的實例時，似乎該函數被一次從每個按鈕調用?！

I want to create multiple buttons and bind them to a function. The problem is that whenever I click on one button, the function is called multiple times. It seems to be a problem with the event connection. When I look at the instance that called the function when I pressed a button, it seems that the function gets called from every button at once?!

...
# This is the button that I'am using
<ProjectSelectButton>:
height: 35
background_color: 0,0,1,1
on_touch_down: self.click_on_button(args[0], args[1])

...

# The buttons are added to this grid
ButtonsPlacedHere@GridLayout:
    id: active_projects
    cols: 1
    size_hint_y: None
    height: self.minimum_height
    spacing: 1
...

Python 代碼:

...
class ProjectSelectButton(Button):
    def click_on_button(self, instance, touch, *args):
        print(instance)
        if touch.button == 'right':
            print(self.id, "right mouse clicked")
        else touch.buttom == 'left':
            print(self.id, "left mouse clicked")

...

# The part of my programm that creates the buttons
# projects is a dictionary
for key, project in data_manager.resource_pool.projects.items():
    print(project.project_name)
    button= ProjectSelectButton(text=project.project_name, id=key, size_hint_y=None)
    # Bind without KV-File (same result)
    # label.bind(on_touch_up=self.click_on_button)
    ids.active_projects.add_widget(button)

示例輸出:

當我點擊一個按鈕時，我得到了什么！

Example Output:

What I get, when I click on a single button!

<guiMain.ProjectSelectButton object at 0x0BA34260>
ID01 right mouse clicked
<guiMain.ProjectSelectButton object at 0x0BA34260>
ID01 right mouse clicked
<guiMain.ProjectSelectButton object at 0x0BA28F10>
ID02 right mouse clicked
<guiMain.ProjectSelectButton object at 0x0BA28F10>
ID02 right mouse clicked
<guiMain.ProjectSelectButton object at 0x0BA22C00>
ID03 right mouse clicked
<guiMain.ProjectSelectButton object at 0x0BA22C00>
ID03 right mouse clicked

當我按下 ID 為 01 的按鈕時我想要什么:

What I want when I press for example the button with ID 01:

<guiMain.ProjectSelectButton object at 0x0BA34260>
ID01 right mouse clicked

問題

如何創建多個按鈕，當它們被按下時會調用一個函數?

Question

How do I create multiple buttons which will call a single function when they are pressed?

推薦答案

編程指南 ? 輸入管理 ? 觸摸事件

默認情況下，觸摸事件會分派給所有當前顯示的小部件.這意味著無論是否發生在其物理區域內，小部件都會接收到觸摸事件.

By default, touch events are dispatched to all currently displayed widgets. This means widgets receive the touch event whether it occurs within their physical area or not.

為了提供最大的靈活性，Kivy 調度所有小部件的事件，并讓它們決定如何對它們做出反應.如果您只想響應小部件內的觸摸事件，您簡單檢查一下.

In order to provide the maximum flexibility, Kivy dispatches the events to all the widgets and lets them decide how to react to them. If you only want to respond to touch events inside the widget, you simply check.

解決方案

在 click_on_button 方法中使用 self.collide_point 方法.當它碰撞時，你應該只得到一個按鈕.詳情請參考我的例子.

Solution

Use self.collide_point method in click_on_button method. When it collides, you should get only one button. Please refer to my example for details.

class ProjectSelectButton(Button):
    def click_on_button(self, instance, touch, *args):
        print(instance)
        if self.collide_point(*touch.pos):
            if touch.button == 'right':
                print(self.id, "right mouse clicked")
            elif touch.buttom == 'left':
                print(self.id, "left mouse clicked")
            return True
        return super(ProjectSelectButton, self).on_touch_down(touch)

示例

main.py

from kivy.app import App
from kivy.uix.gridlayout import GridLayout
from kivy.uix.button import Button


class CreateButton(Button):

    def on_touch_down(self, touch):
        if self.collide_point(*touch.pos):
            if touch.button == "right":
                print(self.id, "right mouse clicked")
            elif touch.button == "left":
                print(self.id, "left mouse clicked")
            else:
                print(self.id)
            return True
        return super(CreateButton, self).on_touch_down(touch)


class OnTouchDownDemo(GridLayout):

    def __init__(self, **kwargs):
        super(OnTouchDownDemo, self).__init__(**kwargs)
        self.build_board()

    def build_board(self):
        # make 9 buttons in a grid
        for i in range(0, 9):
            button = CreateButton(id=str(i))
            self.add_widget(button)


class OnTouchDownApp(App):

    def build(self):
        return OnTouchDownDemo()


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

ontouchdown.kv

#:kivy 1.10.0

<CreateButton>:
    font_size: 50
    on_touch_down: self.on_touch_down

<OnTouchDownDemo>:
    rows: 3
    cols: 3
    row_force_default: True
    row_default_height: 150
    col_force_default: True
    col_default_width: 150
    padding: [10]
    spacing: [10]

這篇關于將函數綁定到kivy中的多個動態創建的按鈕?的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網！