py_*_*der 5 python user-interface tkinter ttk python-3.x
我创建的以下应用程序用于演示tkinter中的多个窗口.主要问题是Entry
bmi-calculator或转换器中的控件都没有接受输入框中的值 - ValueError
当我进行计算时它们会得到一个.
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()
我怎么能解决这个问题,但仍然保持类结构和python3的使用?顺便说一句 - 有什么类似于C#的form1.Show()
?
小智 11
您必须将StringVar()转换为整数/浮点数或使用IntVar()或DoubleVar()
还有其他问题.像下面这样的语句返回"None",因为它是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)
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我想你也会遇到两个同时打开的Tk()窗口的问题.请改用Toplevel()或单独的框架.
谢谢Joe,你帮了很多,我偶然发现了答案...使用ttk你可以使用笔记本,因为我的两个类都是派生帧,我可以把它们添加到笔记本的框架......
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()
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这解决了问题:)