只接受一个参数（给定 0）

Question

class bmicalculator():
     #class created for the bmi calculator GUI and processing the numbers (pain in the ass to make)#
     def __init__(self,master):

          self.heightcm=DoubleVar()
          self.weightkg=DoubleVar()

          self.master=master
          self.master.geometry('250x200+100+200')
          self.master.title('BMI Calculator')

          self.label2=Label(self.master,text='Welcome to the BMI Calculator',fg='red').grid(row=0,column=0)
          self.label2=Label(self.master,text='Please enter your height in centimetres',fg='black').grid(row=3,column=0)
          self.label2=Label(self.master,text='Please enter your weight in kilograms',fg='black').grid(row=4,column=0)

          self.myheight=Entry(self.master,textvariable=self.heightcm).grid(row=3,column=1)
          self.myweight=Entry(self.master,textvariable=self.weightkg).grid(row=4,column=1)
          self.button4=Button(self.master,text="Calculate BMI",fg='red',command=self.bmicalculation).grid(row=7,column=0)
          self.button5=Button(self.master,text="Exit",fg='red',command=self.exit).grid(row=9,column=0)

     def bmicalculation(self):
          bmiheight=self.heightcm.get()
          print bmiheight
          bmiweight=self.weightkg.get()
          bmi= float((bmiweight)/((bmiheight / 100)**2))
          self.bmi = bmi
          print bmi
          self.label1=Label(self.master,text='Your BMI is %.2f' % bmi).grid(row=5,column=0)

          if bmi <= 18.5:
               self.label2=Label(self.master,text='This places you in the underweight group.',fg='blue').grid(row=6,column=0)
               totalindex = 'underweight'
               self.totalindex = totalindex
          elif bmi >18.5 and bmi <25:
               self.label3=Label(self.master,text='This places you in the healthy weight group.',fg='green').grid(row=6,column=0)
               totalindex = 'healthy'
               self.totalindex = totalindex
          elif bmi >= 25 and bmi < 30:
               self.label4=Label(self.master,text='This places you in the overweight group.',fg='orange').grid(row=6,column=0)
               totalindex = 'overweight'
               self.totalindex = totalindex
          elif bmi >=30:
               self.label5=Label(self.master,text='This places you in the obese group.',fg='red').grid(row=6,column=0)
               totalindex = 'obese'
               self.totalindex = totalindex

          if bmi >0 and bmi <999999999999999999999:
               self.button6=Button(self.master,text="Store Data",fg='red',command=self.dynamic_data_entry).grid(row=8,column=0)

     def dynamic_data_entry(self):
        #this is what adds the data to the database. Bmi has to be changed to the value of bmi and weightclass has to be change to the weightclass
          timestamp = str(datetime.datetime.now().date())
          bodymassindex = self.bmi
          weightclass = self.totalindex
          c.execute("INSERT INTO BMIStorage (timestamp, bodymassindex, weightclass) VALUES (?, ?, ?)",(timestamp, bodymassindex, weightclass))
          conn.commit()
          create_table()

     def create_table():
          c.execute('CREATE TABLE IF NOT EXISTS BMIStorage(timestamp TEXT,bmi REAL,weightclass TEXT)')

得到dynamic_data_entry 只接受一个参数（给定0）的错误。我不知道如何解决或出了什么问题。这是带有 GUI 的 BMI 的代码，我想将用户的输入连同日期一起写入数据库。我无法将输入中的数据写入数据库。

** 函数是一个类的方法 *** 更新添加全班

Answer 1

我想我发现了你的错误。

您正在通过这种方式将用作 command 的函数传递给您的 Button 类：

self.button6=Button(...., command=self.dynamic_data_entry).grid(row=8,column=0)

但是，一旦方法本身需要一个隐式参数，即self，您将立即传递该方法，这将导致您得到Error。

这个self 表示您班级的对象。但是当您直接传递方法时，不涉及任何对象。

因此，您应该这样做：

 obj = bmicalculator(master)
 self.button6=Button(...., command=obj.dynamic_data_entry).grid(row=8,column=0)

这样，您告诉Button 类从对象调用方法，在这种情况下，self 参数将存在，因为实例化对象存在。

确保您了解command=self.dynamic_data_entry 和command=obj.dynamic_data_entry 之间的区别