获取 Text tkinter 小部件的行数 [英] Get of number of lines of a Text tkinter widget

问题描述

我得到 tkinter Text 小部件的行数，如下所示:

I get the number of lines of a tkinter Text widget like this:

import Tkinter as Tk

def countlines(event):
    print float(event.widget.index(Tk.END))-1 
    print event.widget.get("1.0", Tk.END).count("\n")

root = Tk.Tk()
root.geometry("200x200")
a = Tk.Text(root)
a.pack()
a.bind("<Key>", countlines)

root.mainloop()

唯一的问题:当你点击 时，行数没有增加.您需要添加一些其他文本，以便增加行数.

Only problem : when you hit <Return>, the count of lines doesn't increase. You need to add some futher text in order that count of lines increases.

如何做到这一点 <Return > 键增加行数?

推荐答案

不要获取所有的文本然后计数，只需用 index("end-1c") 然后做一些字符串操作来获取行号.

Don't get all the text and then count, just get the index of the last-minus-one character with index("end-1c") and then do some string manipulation to get the line number.

至于为什么数字没有增加，那是因为您的绑定发生在之前插入返回键.对于您的简单测试，您可以通过绑定 <KeyRelease> 来解决此问题，因为字符已插入到印刷机上.

As for why the number doesn't increase, it's because your binding happens before the return key is inserted. For your simple test you can work around this by binding on <KeyRelease>, since the character is inserted on the press.

import Tkinter as Tk

def countlines(event):
    (line, c) = map(int, event.widget.index("end-1c").split("."))
    print line, c

root = Tk.Tk()
root.geometry("200x200")
a = Tk.Text(root)
a.pack()
a.bind("<KeyRelease>", countlines)

root.mainloop()

如果您需要在按键上打印值，则必须使用称为bindtags"的高级功能.对此问题的回答中简要介绍了绑定标签:关于绑定标签的基本查询tkinter.简而言之，您必须创建一个出现在类 bindtag 之后的自定义 bindtag，以便您的绑定发生在类绑定之后.​​

If you need to print the value on the key press, you'll have to use an advanced feature called "bindtags". Bindtags are covered briefly in an answer to this question: Basic query regarding bindtags in tkinter. In short, you have to create a custom bindtag that appears after the class bindtag, so that your binding happens after the class binding.

以下是修改程序以使用绑定标签的方法:

Here's how to modify your program to use bindtags:

import Tkinter as Tk

def countlines(event):
    (line, c) = map(int, event.widget.index("end-1c").split("."))
    print line, c

root = Tk.Tk()
root.geometry("200x200")
a = Tk.Text(root)
a.pack()
bindtags = list(a.bindtags())
bindtags.insert(2, "custom")
a.bindtags(tuple(bindtags))
a.bind_class("custom", "<Key>", countlines)

root.mainloop()

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