关于python中的tkinter中的tk.Button()的按钮显示问题

Question

为什么我的这行两行代码加入这个command之后，运行时的“确定”、“取消”按钮就消失了

self.btn1 = tk.Button(self, text='取消', command=self.btn1cal2())
self.btn1 = tk.Button(self, text='确定',command=self.btn1cal1())

下面是我的全部代码：

import tkinter as tk
class Window1(tk.Tk):
    def __init__(self):
        super().__init__()
        self.title("0")
        self.geometry('200x100+400+200')
        self.resizable(False, False)  # 窗口大小可调整=False
        # self.protocol("WM_DELETE_WINDOW",True)
        self.myinitgui()
    def myinitgui(self):        #创建用户界面
        self.label1=tk.Label(self,text='是否关闭？')  #标签A
        self.label1.place(x=70,y=15)    #放置
        self.btn1 = tk.Button(self, text='取消', command=self.btn1cal2())
        self.btn1.place(x=25, y=50, width=70, height=30)
        self.btn1 = tk.Button(self, text='确定',command=self.btn1cal1())
        self.btn1.place(x=100, y=50, width=70, height=30)
    def btn1cal1(self):
        i=0
        while(i<10):
            wrong=Wrong()
            i=i+1
            wrong.mainloop()

    def btn1cal2(self):
        i = 0
        while (i < 10):
            wrong = Wrong()
            i = i + 1
            wrong.mainloop()

class Wrong(tk.Tk):
    def __init__(self):
        super().__init__()
        self.title("010")
        height=random.randint(0,800)
        width=random.randint(0,600)
        self.geometry('200x100+%s+%s'%(height,width))
        self.resizable(False, False)  # 窗口大小可调整=False
        self.label1 = tk.Label(self, text='程序一经启动将无法关闭！')  # 标签A
        self.label1.place(x=10, y=15)  # 放置
if __name__=='__main__':
    window1= Window1()
    window1.mainloop()

Answer 1

函数后面不能加括号，应该这样写command=self.btn1cal2