Python Kivy中的滑块小部件用法示例

Kivy是Python中与平台无关的GUI工具。由于它可以在Android, IOS, Linux和Windows等操作系统上运行。它基本上是用于开发Android应用程序, 但这并不意味着它不能在桌面应用程序上使用。

????Kivy教程–通过示例学习Kivy。

滑杆：
要使用滑块, 首先必须导入包含滑块的所有功能和功能的模块, 即

Module: kivy.uix.slider

Slider小部件看起来像我们在android中使用的一样, 以增加亮度, 音量等。它支持水平和垂直方向, 最小/最大值和默认值。 Kivy支持多个滑块小部件选项, 用于自定义要在不同方向上使用的光标, 光标图像, 边框, 背景, 最小值和最大值之间的区域。
Kivy还支持处理归一化值(范围0到1), 而不是滑块支持的实际范围。

创建Slider时要遵循的基本方法：1)导入kivy 2)导入kivy App 3)导入gridlayout(根据需要不是强制性的)4)导入Label(根据需要不是强制性的)5)导入Slider 6)导入数字属性7)设置最低版本(可选)8)扩展类9)添加并返回小部件10)运行该类的实例

以下是代码实现滑块：

# import kivy module import kivy # this restrict the kivy version i.e # below this kivy version you cannot # use the app or software kivy.require( "1.9.1" )# Kivy Example App for the slider widget from kivy.app import App# The GridLayout arranges children in a matrix. from kivy.uix.gridlayout import GridLayout# If we will not import this module # It will through the error from kivy.uix.slider import Slider# The Label widget is for rendering text. from kivy.uix.label import Label# Property that represents a numeric value # within a minimum bound and /or maximum # bound – within a numeric range. from kivy.propertiesimport NumericProperty# class in which we are defining the # sliders and its effects class WidgetContainer(GridLayout):def __init__( self , * * kwargs):# super function can be used to gain access # to inherited methods from a parent or sibling # class that has been overwritten in a class object. super (WidgetContainer, self ).__init__( * * kwargs)# 4 columns in grid layout self .cols = 4# declaring the slider and adding some effects to it self .brightnessControl = Slider( min = 0 , max = 100 )# 1st row - one label, one slider self .add_widget(Label(text = 'brightness' )) self .add_widget( self .brightnessControl) # 2nd row - one label for caption, # one label for slider value self .add_widget(Label(text = 'Slider Value' )) self .brightnessValue = http://www.srcmini.com/Label(text ='0' ) self .add_widget( self .brightnessValue)# On the slider object Attach a callback # for the attribute named value self .brightnessControl.bind(value = http://www.srcmini.com/self .on_value)# Adding functionality behind the slider # i.e when pressed increase the value def on_value( self , instance, brightness): self .brightnessValue.text ="% d" % brightness# The app class class SliderExample(App): def build( self ): widgetContainer = WidgetContainer() return widgetContainer# creating the object root for ButtonApp() class root = SliderExample()# run function runs the whole program # i.e run() method which calls the # target function passed to the constructor. root.run()

输出如下：

文章图片
要为滑块添加一些样式和颜色, 只需将42号行替换为下面的行, 并根据需要添加一些新功能。对于文本, 样式在文本部分使用适当的命令。

# declaring the slider and adding some effects to it # By default its orientation is horizontal # if want to change to vertical do like below self .brightnessControl = Slider( min = 0 , max = 100 , orientation = 'vertical' , value_track = True , value_track_color = [ 1 , 0 , 0 , 1 ])

输出如下：