给控件绑定事件，当发生该事件时，调用函数

widget.bind('<event>', function)

Event事件

语法格式

<modifier-modifier-type-detail>

modifier修饰符

type事件类型

实例

import tkinter as tk
import tkinter.messagebox


class App(tk.Tk):

    def __init__(self):
        super().__init__()
        self.geometry('600x400')
        self.set_widget()
        self.bind_event()
        self.mainloop()
    
    def set_widget(self):
        self.frm = tk.Frame(self)
        self.frm.pack()

        tk.Label(self.frm,text='账号').grid(row=0,column=0)
        tk.Label(self.frm,text='密码').grid(row=1,column=0,pady=10)

        self.tip = tk.StringVar()
        self.tip.set('请输入邮箱或者手机号')

        self.ety_name = tk.Entry(self.frm,textvariable=self.tip,fg='gray')
        self.ety_name.grid(row=0,column=1,columnspan=3)

        self.ety_pwd = tk.Entry(self.frm)
        self.ety_pwd.grid(row=1,column=1,columnspan=3)

        self.btn_yes = tk.Button(self.frm,text='确定(y)',width=8,command=self.show,underline=3)
        self.btn_yes.grid(row=2,column=3)

        self.btn_cancel = tk.Button(self.frm,text='取消(d)',width=8,underline=3,command=self.show2)
        self.btn_cancel.grid(row=2,column=1)


        

    def bind_event(self):
        self.ety_name.bind('<FocusIn>',self.delete_tip)

        self.ety_name.bind('<FocusOut>',self.add_tip)

        self.ety_pwd.bind('<Return>',self.__show)   # 当在密码输入框输入完，按回车键就可以，触发函数。点击了确定按钮

        # 设置快捷键

        self.bind('<Control-y>',self.__show)

        self.bind('<Control-d>',self.__show2)
    

    def add_tip(self,evnet):
        
        ety_name = self.ety_name.get()

        if ety_name == '':
            self.tip.set('请输入邮箱或者手机号')
            self.ety_name.config(fg='gray')
            tkinter.messagebox.showerror(message='账号不能为空')


    def delete_tip(self,event):
        ety_name = self.ety_name.get()

        if ety_name == '请输入邮箱或者手机号':
            self.ety_name.delete(0,'end')
            self.ety_name.config(fg='black')
    
    def show(self):
        name = self.ety_name.get()
        tkinter.messagebox.showinfo(message=f'welecom {name}')

    def __show(self,event):
        self.show()

    def show2(self):
        tkinter.messagebox.showinfo(message='you press cancel')
    def __show2(self,event):
        self.show2()

App()

Event事件对象

当事件触发后，Tkinter 会自动将事件对象交给回调函数进行下步的处理，Event 对象包含了以下常用属性：

type对应的数字

    KeyPress = '2'
    Key = KeyPress,
    KeyRelease = '3'
    ButtonPress = '4'
    Button = ButtonPress,
    ButtonRelease = '5'
    Motion = '6'
    Enter = '7'
    Leave = '8'
    FocusIn = '9'
    FocusOut = '10'
    Keymap = '11'           # undocumented
    Expose = '12'
    GraphicsExpose = '13'   # undocumented
    NoExpose = '14'         # undocumented
    Visibility = '15'
    Create = '16'
    Destroy = '17'
    Unmap = '18'
    Map = '19'
    MapRequest = '20'
    Reparent = '21'
    Configure = '22'
    ConfigureRequest = '23'
    Gravity = '24'
    ResizeRequest = '25'
    Circulate = '26'
    CirculateRequest = '27'
    Property = '28'
    SelectionClear = '29'   # undocumented
    SelectionRequest = '30' # undocumented
    Selection = '31'        # undocumented
    Colormap = '32'
    ClientMessage = '33'    # undocumented
    Mapping = '34'          # undocumented
    VirtualEvent = '35',    # undocumented
    Activate = '36',
    Deactivate = '37',
    MouseWheel = '38',

这样使用上面的type对应数字，就不用写多个函数来处理事件。