使用Tkinter在闪烁的光标下方打开一个新窗口

Question

通常我们得到坐标，然后在那里打开一个新窗口。我需要的是在Tkinter文本框闪烁光标的正下方打开一个窗口。我不知道如何根据屏幕中像素的高度和宽度获得那个坐标。

Answer 1

您需要获取文本小部件相对于屏幕的当前位置，以及小部件插入光标的边界框，它相对于小部件。

如果文本小部件的某个元素当前不可见，则其边界框为None；在这种情况下，您需要使用滚动文本。请参见使元素可见的方法。

这个程序是为Python2编写的，因此如果在Python3上运行它，需要将import语句更改为import tkinter as tk。

#!/usr/bin/env python

''' Text Location Demo
    Open a Tkinter window just under the location of the insertion cursor 
    of a Text widget.

    See http://stackoverflow.com/q/34237313/4014959

    Written by PM 2Ring 2015.12.12
'''

import Tkinter as tk

#Some random text to display in the Text widget
lorem_ipsum = '''Lorem ipsum dolor sit amet, consectetur adipiscing
elit. Aenean lacinia tortor quis quam vehicula semper. Curabitur
faucibus, purus a egestas bibendum, velit metus hendrerit nulla, non
lobortis dolor mi in dolor. Aliquam ultrices felis sit amet dolor
gravida, id ullamcorper odio rutrum. Fusce consectetur tempor nibh, non
dictum dolor dictum nec. In hac habitasse platea dictumst. Morbi laoreet
consequat metus, at lacinia nisl suscipit id. Quisque vitae sodales
velit, a lobortis nisl. Praesent varius convallis efficitur. Vivamus
fringilla at risus nec viverra. Proin suscipit, lorem sed laoreet
ultricies, velit massa ornare nunc, vel egestas nibh ex vitae leo.'''

lorem_ipsum = lorem_ipsum.replace('\n', ' ')

class TextLocationDemo(object):
    ''' Text widget cursor location demo '''
    def __init__(self):
        root = tk.Tk()
        root.title("Text Location Demo")

        tk.Button(root, text="Show cursor location", 
            command=self.location_cb).pack()

        # Create a Text widget, with word wrapping
        self.textwidget = tw = tk.Text(root, wrap=tk.WORD)
        tw.pack()
        tw.insert(tk.END, lorem_ipsum)

        root.mainloop()

    def alert(self, geometry, msg):
        ''' Display `msg` in an Alert with given geometry,
            which is a tuple of (width, height, ox, oy)
        '''
        top = tk.Toplevel()
        # widget geometry parameter must be given in X windows format
        top.geometry("%dx%d%+d%+d" % geometry)

        msg = tk.Message(top, text=msg, width=geometry[0])
        msg.pack()

        button = tk.Button(top, text="Ok", command=top.destroy)
        button.pack()

    def location_cb(self):
        ''' Determine the location of the insertion cursor
            and display it in a window just under that location
        '''
        w = self.textwidget

        # Get the Text widget's current location
        pos_x, pos_y = w.winfo_rootx(), w.winfo_rooty()

        # Get the bounding box of the insertion cursor
        cursor = tk.INSERT
        bbox = w.bbox(cursor)
        if bbox is None:
            print('Cursor is not currently visible. Scrolling...')
            w.see(cursor)
            bbox = w.bbox(cursor)

        bb_x, bb_y, bb_w, bb_h = bbox

        #Open a window just beneath the insertion cursor
        width = 200
        height = 80
        ox = pos_x + bb_x
        oy = pos_y + bb_y + bb_h
        s = 'Cursor: (%d, %d)' % (ox, oy)
        print(s)

        geometry = (width, height, ox, oy)
        self.alert(geometry, s)


TextLocationDemo()