ttk tkinter 多个框架/窗口

Question

我创建的这个应用程序是用来展示在tkinter中如何使用多个窗口的。主要的问题是，bmi计算器和转换器中的所有Entry控件都无法接受输入框中的值——当我进行计算时，会出现ValueError错误。

from tkinter import *
from tkinter import ttk
from tkinter import messagebox

class App1(ttk.Frame):
    def createWidgets(self):
        #text variables
        self.i_height = StringVar()
        self.i_weight = StringVar()
        self.o_bmi = StringVar()

        #labels
        self.label1 = ttk.Label(self, text="Enter your weight:").grid(row=0, column=0, sticky=W)
        self.label2 = ttk.Label(self, text="Enter your height:").grid(row=1, column=0, sticky=W)
        self.label3 = ttk.Label(self, text="Your BMI is:").grid(row=2, column=0, sticky=W)

        #text boxes
        self.textbox1 = ttk.Entry(self, textvariable=self.i_weight).grid(row=0, column=1, sticky=E)
        self.textbox2 = ttk.Entry(self, textvariable=self.i_height).grid(row=1, column=1, sticky=E)
        self.textbox3 = ttk.Entry(self, textvariable=self.o_bmi).grid(row=2, column=1, sticky=E)

        #buttons
        self.button1 = ttk.Button(self, text="Cancel/Quit", command=self.quit).grid(row=3, column=1, sticky=E)
        self.button1 = ttk.Button(self, text="Ok", command=self.calculateBmi).grid(row=3, column=2, sticky=E)

    def calculateBmi(self):
        try:
            self.weight = float(self.i_weight.get())
            self.height = float(self.i_height.get())
            self.bmi = self.weight / self.height ** 2.0
            self.o_bmi.set(self.bmi)
        except ValueError:
            messagebox.showinfo("Error", "You can only use numbers.")
        finally:
            self.i_weight.set("")
            self.i_height.set("")

    def __init__(self, master=None):
        ttk.Frame.__init__(self, master)
        self.grid()
        self.createWidgets()

class App2(ttk.Frame):
    def create_widgets(self):
        """Create the widgets for the GUI"""
        #1 textbox (stringvar)
        self.entry= StringVar()
        self.textBox1= ttk.Entry(self, textvariable=self.entry).grid(row=0, column=1)

        #5 labels (3 static, 1 stringvar)
        self.displayLabel1 = ttk.Label(self, text="feet").grid(row=0, column=2, sticky=W)
        self.displayLabel2 = ttk.Label(self, text="is equivalent to:").grid(row=1, column=0)
        self.result= StringVar()
        self.displayLabel3 = ttk.Label(self, textvariable=self.result).grid(row=1, column=1)
        self.displayLabel4 = ttk.Label(self, text="meters").grid(row=1, column=2, sticky=W)

        #2 buttons
        self.quitButton = ttk.Button(self, text="Quit", command=self.quit).grid(row=2, column=1, sticky=(S,E))
        self.calculateButton = ttk.Button(self, text="Calculate", command=self.convert_feet_to_meters).grid(row=2, column=2, sticky=(S,E))

    def convert_feet_to_meters(self):
        """Converts feet to meters, uses string vars and converts them to floats"""
        self.measurement = float(self.entry.get())
        self.meters = self.measurement * 0.3048
        self.result.set(self.meters)

    def __init__(self, master=None):
        ttk.Frame.__init__(self, master)
        self.grid()
        self.create_widgets()

def button1_click():
    root = Tk()
    app = App1(master=root)
    app.mainloop()

def button2_click():
    root = Tk()
    app = App2(master=root)
    app.mainloop()

def main():
    window = Tk()
    button1 = ttk.Button(window, text="bmi calc", command=button1_click).grid(row=0, column=1)
    button2 = ttk.Button(window, text="feet conv", command=button2_click).grid(row=1, column=1)
    window.mainloop()

if __name__ == '__main__':
    main()

我该如何解决这个问题，同时又保持类的结构和使用python3呢？顺便问一下，有没有类似于C#中form1.Show()的东西？

Answer 1

谢谢你，Joe，你帮了我很多，我找到了答案... 使用ttk可以用到笔记本控件，因为我的两个类都是从框架派生出来的，我可以直接把它们添加到笔记本的框架里...

def main():
#Setup Tk()
window = Tk()

#Setup the notebook (tabs)
notebook = ttk.Notebook(window)
frame1 = ttk.Frame(notebook)
frame2 = ttk.Frame(notebook)
notebook.add(frame1, text="BMI Calc")
notebook.add(frame2, text="Feet to Meters")
notebook.grid()

#Create tab frames
app1 = App1(master=frame1)
app1.grid()
app2 = App2(master=frame2)
app2.grid()

#Main loop
window.mainloop()

这样就解决了问题 :)

Answer 2

你需要把 StringVar() 转换成整数或浮点数，或者直接使用 IntVar() 或 DoubleVar()。

还有其他问题。像下面这样的语句会返回“None”，因为它是一个 grid() 对象，而不是 Label() 对象：

self.label1 = ttk.Label(self, text="Enter your weight:").grid(row=0, column=0, sticky=W)   

我觉得如果同时打开两个 Tk() 窗口，你也会遇到问题。可以使用 Toplevel() 或者分开使用不同的框架。