我编写了以下tkinter脚本来了解如何将数据列表添加到tkinter.Listbox小部件中.我发现了两种方法.
接下来,我想从tkinter.Listbox小部件中提取相同的列表.在4种不同的方法中,我只设法让第4种方法(即e4)起作用.
如何使e1,e2和e3方法起作用？最终目标是获取最初提供给tkinter.Listbox小部件的相同列表.
测试脚本：
import tkinter as tk # Python 3 tkinter modules
import tkinter.ttk as ttk
class App(ttk.Frame):
def __init__(self, parent, *args, **kwargs):
# 1. Initialise Frame
ttk.Frame.__init__(self, parent)
self.parent = parent
# Method1
name1 = ['Peter', 'Scotty', 'Walter', 'Scott', 'Mary']
self.lb1_values = tk.StringVar(value=name1)
self.listbox1 = tk.Listbox(self, listvariable=self.lb1_values)
# Method2
self.listbox2 = tk.Listbox(self)
name2 = ['Sarah', 'Sean', 'Mora', 'Mori', 'Mary']
for item in name2:
self.listbox2.insert(tk.END, item)
self.listbox1.grid(in_=self, row=0, column=0, sticky='nsew')
self.listbox2.grid(in_=self, row=0, column=1, sticky='nsew')
# Extract values from listbox and covert to a list
e1 = self.lb1_values.get()
print('e1 = ', e1)
print('type(e1) = ', type(e1))
e1 = e1.strip(',')
print('e1 = ', e1)
e2 = self.listbox1.cget('listvariable')
print('\ne2 = ', e2)
print('type(e2) = ', type(e2))
e2 = e2.split(',')
print('e2 = ', e2)
e3 = self.listbox2.cget('listvariable')
print('\ne3 = ', e3)
print('type(e3) = ', type(e3))
e4 = self.listbox2.get(0, tk.END)
print('\ne4 = ', e4)
print('type(e4) = ', type(e4))
e4 = list(e4)
print('e4 = ', e4)
if __name__ == '__main__':
root = tk.Tk()
root.title('App'), root.geometry('400x200')
app = App(root)
app.grid(row=0, column=0, sticky='nsew')
#root.mainloop()
输出：
e1 = ('Peter', 'Scotty', 'Walter', 'Scott', 'Mary')
type(e1) =
e1 = ('Peter', 'Scotty', 'Walter', 'Scott', 'Mary')
e2 = PY_VAR0
type(e2) =
e2 = ['PY_VAR0']
e3 =
type(e3) =
e4 = ('Sarah', 'Sean', 'Mora', 'Mori', 'Mary')
type(e4) =
e4 = ['Sarah', 'Sean', 'Mora', 'Mori', 'Mary']
解决方法:
您不能将StringVar用作listvariable属性的目标.正如您的代码所示,这会导致列表转换为字符串.
但是,你可以做的是使用tk.Variable的一个实例. Variable是StringVar的基类. get的基本实现不会将值强制转换为字符串.
name1 = ['Peter', 'Scotty', 'Walter', 'Scott', 'Mary']
self.lb1_values = tk.Variable(value=name1)
self.listbox1 = tk.Listbox(self, listvariable=self.lb1_values)
...
e1 = self.lb1_values.get()
print('e1 = ', e1)
print('type(e1) = ', type(e1))
print('e1 = ', e1)
以上产生了这个输出：
e1 = ('Peter', 'Scotty', 'Walter', 'Scott', 'Mary')
type(e1) =
e1 = ('Peter', 'Scotty', 'Walter', 'Scott', 'Mary')
对于e2和e3,你必须跳过额外的箍.遗憾的是,cget方法返回内部变量名而不是对变量对象的引用.要按名称获取变量的值,您需要使用widget方法getvar.
例如：
e2 = self.listbox1.cget('listvariable')
print('\ne2 = ', e2)
print('type(e2) = ', type(e2))
print('e2 = ', self.getvar(e2))
以上产生了这个输出：
e2 = PY_VAR0
type(e2) =
e2 = ('Peter', 'Scotty', 'Walter', 'Scott', 'Mary')
标签：python,listbox,tkinter
来源： https://codeday.me/bug/20190607/1195248.html
