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帮助！

我创建了一个模仿机顶盒的简单 GUI。除了一个之外，所有功能都在工作。

当输入从“电视”更改为“收音机”时，我希望显示“频道”的标签默认恢复为 1。

与标签关联的 IntVar 是 self.chan_value。我尝试设置单选按钮选项命令 = self.chan_value.set(1)，但是当我按下单选按钮时仍然没有任何反应。

当连接到通道输入框的函数调用时，使用 self.chan_value.set(1) 似乎工作正常，但我没有运气让单选按钮工作。

我试过定义一个方法，如：

def chan_resetter(self):   
     self.chan_value.set(1)

但这似乎与仅仅设置命令并没有什么不同。这是我的代码。问题出在“输入帧”部分，有两个单选按钮 tv_rb 和 radio_rb

import tkinter
import tkinter.messagebox


class MySetTopBox:


    def __init__(self):


        self.main_window = tkinter.Tk()

        # frames
        self.power_frame = tkinter.Frame(self.main_window)
        self.input_frame = tkinter.Frame(self.main_window)

        # (channel frames)
        self.top_frame = tkinter.Frame(self.main_window)
        self.mid_frame = tkinter.Frame(self.main_window)

        self.volume_frame = tkinter.Frame(self.main_window)
        self.quit_frame = tkinter.Frame(self.main_window)



        # channel frame

        # top frame
        self.desc_label = tkinter.Label(self.top_frame, text='CHANNEL:')
        self.chan_value = tkinter.StringVar()
        self.chan_value.set(1)
        self.chan_label = tkinter.Label(self.top_frame, textvariable = self.chan_value)        

        self.desc_label.pack(side='left')
        self.chan_label.pack(side='left')

        # mid frame
        self.change_button = tkinter.Button(self.mid_frame, text='Change Channel', command= self.channel_function)
        self.chan_entry = tkinter.Entry(self.mid_frame, width = 10)

        self.chan_entry.pack(side='left') 
        self.change_button.pack(side='left')



        # input frame 

        chan_resetter = self.chan_value.set(1)

        self.input_var = tkinter.IntVar()
        self.input_var.set(1)

        self.input_label = tkinter.Label(self.input_frame, text='INPUT')
        self.tv_rb = tkinter.Radiobutton(self.input_frame, text='TV', variable=self.input_var, value = 1, command= chan_resetter, indicatoron=0, width=5, padx=20)
        self.radio_rb = tkinter.Radiobutton(self.input_frame, text='RADIO', variable=self.input_var, value = 2, command= chan_resetter, indicatoron=0, width=5, padx=20)

        self.input_label.pack()
        self.tv_rb.pack(side='left')
        self.radio_rb.pack(side='left')



        # volume frame
        self.volume_var = tkinter.IntVar()
        self.volume_var.set(5)

        self.volume_label = tkinter.Label(self.volume_frame, text='VOLUME')
        self.volume_scale = tkinter.Scale(self.volume_frame, from_=0, to_=10, variable=self.volume_var)

        self.volume_label.pack(side='top')
        self.volume_scale.pack(side='left')        



        # quit frame

        self.quit_button = tkinter.Button(self.quit_frame, text='Quit', command= self.main_window.destroy)
        self.quit_button.pack(side='left') 

        self.power_var = tkinter.IntVar()
        self.power_var.set(2)



        # power frame
        self.casey_label = tkinter.Label(self.power_frame, text="Casey's Set Top Box")
        self.power_label = tkinter.Label(self.power_frame, text='POWER')
        self.on_rb = tkinter.Radiobutton(self.power_frame, text='ON', variable=self.power_var, value=1,command=self.default_function())
        self.off_rb = tkinter.Radiobutton(self.power_frame, text='OFF', variable=self.power_var, value=2)

        self.casey_label.pack(side='top')
        self.power_label.pack()
        self.on_rb.pack(side='left')
        self.off_rb.pack(side='left')      



        # pack frames

        self.power_frame.pack()
        self.input_frame.pack()
        self.top_frame.pack()
        self.mid_frame.pack()
        self.volume_frame.pack()
        self.quit_frame.pack()


        tkinter.mainloop()



    def default_function(self):
        self.input_var.set(1)
        self.chan_value.set(1)
        self.volume_var.set(5)     
        #include messagebox? 'you have turned the power off'



    def channel_function(self):
        new_chan = int(self.chan_entry.get())
        input_current = self.input_var.get()
        power_off = self.power_var.get()
        if power_off ==2:
            tkinter.messagebox.showinfo('Error', 'Turn Set Top Box power ON first') 

        elif input_current == 1 and new_chan > 30:
            tv_error = 'ERROR: TV channels range from 1 to 30'
            tkinter.messagebox.showinfo('Error', tv_error)

        elif input_current == 2 and new_chan > 12:
            radio_error = 'ERROR: Radio channels range from 1 to 12'
            tkinter.messagebox.showinfo('Error', radio_error)

        else:
            self.chan_value.set(new_chan)


    def volume_function(self):
        vol_entered = self.volume_var.get()
        self.volume_var.set(vol_entered) 



my_stb = MySetTopBox()

print (my_stb.input_var.get())
print (my_stb.chan_value.get())
print (my_stb.volume_var.get())
4

1 回答 1

0

使用lambda功能

command=lambda:self.chan_value.set(1)

.

self.tv_rb = tkinter.Radiobutton(self.input_frame, text='TV', variable=self.input_var, value = 1, command=lambda:self.chan_value.set(1), indicatoron=0, width=5, padx=20)

chat_resetter或以这种方式创建函数

def chan_resetter():
   self.chan_value.set(1)

self.tv_rb = tkinter.Radiobutton(self.input_frame, text='TV', variable=self.input_var, value = 1, command=chan_resetter, indicatoron=0, width=5, padx=20)

chan_resetter必须__init__像其他指令一样在内部（相同的缩进） - 它不是类中MySetTopBox的另一个函数，而是__init__

但是你总是可以在类中定义chan_resetter为另一个函数MySetTopBox

def chan_resetter(self):
   self.chan_value.set(1)

然后用lambda它来调用它

command=lambda:chan_resetter(self)

chan_resetter = self.chan_value.set(1)

上面的代码意味着 - 设置chan_value和1结果分配给chan_resetter但self.chan_value.set(1)结果给None所以你得到chan_resetter = None

command=self.chan_value.set(1)

上面的代码意味着相同的 - 运行self.chan_value.set(1)和结果分配给command所以你得到command=None

于 2013-11-14T02:43:51.520 回答