如何在Tkinter中向上或向下移动项目而不会丢失他们的选择？

Question

我有下面的代码,它创建一个简单的列表框,并允许用户选择项目并在列表中向上或向下移动它们,从而重新排列列表.

我现在遇到的问题是每次按"向上移动"或"向下移动"时,操作都会正确执行,但光标不再保持选中状态.我必须重新选择该项目才能再次执行该功能.

我在设置列表框时尝试配置exportselection = False,但这不起作用.

import tkinter as tk

class SampleApp(tk.Tk):
    def __init__(self, *args, **kwargs):
        tk.Tk.__init__(self, *args, **kwargs)
        self.wm_title("Animals")
        self._frame = None

class AnimalPage(tk.Frame):
    def __init__(self, master, controller):
        tk.Frame.__init__(self, master)
        self.master = master
        self.controller = controller
        self.config(relief='sunken', borderwidth=2)
        self.pack(fill = "both", expand = False)
        tk.Label(self, text="This is the Animal Configuration Page").pack()

        self.animalList = ['Cat', 'Dog', 'Bear', 'Dolphin', 'Kangaroo']
        self.animalString = tk.StringVar(value=self.animalList)
        self.animalBox = tk.Listbox(self, listvariable=self.animalString,
                                height=25, width=50, borderwidth=2)
        self.animalBox.pack()

        moveUpButton = tk.Button(self, text="Move Up", command=lambda: self.moveup())
        moveUpButton.pack()
        moveDownButton = tk.Button(self, text="Move Down", command=lambda: self.movedown())
        moveDownButton.pack()

    def moveup(self, *args):
        try:
            self.idxs = self.animalBox.curselection()
            if not self.idxs:
                return
            for pos in self.idxs:
                if pos==0:
                    continue
                text=self.animalBox.get(pos)
                self.animalBox.delete(pos)
                self.animalBox.insert(pos-1, text)
                self.animalList.pop(pos)
                self.animalList.insert(pos-1, text)
        except:
            pass

    def movedown(self, *args):
        try:
            self.idxs = self.animalBox.curselection()
            if not self.idxs:
                return
            for pos in self.idxs:
                if pos==0:
                    continue
                text=self.animalBox.get(pos)
                self.animalBox.delete(pos)
                self.animalBox.insert(pos+1, text)
                self.animalList.pop(pos)
                self.animalList.insert(pos+1, text)
        except:
            pass

if __name__ == "__main__":
    app = SampleApp()
    newFrame = AnimalPage(app, app)
    app.geometry("1200x700")
    app.mainloop()

Answer 1

只需使用selection_set来保留所选项目,如下所示:

 def moveup(self, *args):
    try:
        self.idxs = self.animalBox.curselection()
        if not self.idxs:
            return
        for pos in self.idxs:
            if pos==0:
                continue
            text=self.animalBox.get(pos)
            self.animalBox.delete(pos)
            self.animalBox.insert(pos-1, text)
            self.animalList.pop(pos)
            self.animalList.insert(pos-1, text)
            self.animalBox.selection_set(pos-1)
    except:
        pass

同样对于搬迁.