如何修改Tkinter的CreateToolTip类实现可变wraplength？

刚好我对这个经典的Tkinter ToolTip类很熟悉，要实现每次创建时自定义换行宽度，只需要修改几个关键地方，我给你拆解一下：

需要修改的核心部分 #

• 调整__init__方法的参数顺序与默认值：把wraplength作为第二个参数加入，同时保留默认值180（这样不指定宽度的旧代码依然能正常运行），参数顺序改成widget, wraplength=180, text='widget info'，完美匹配你想要的CreateToolTip(widget_name, tooltip_width, "提示内容")调用格式。
• 更新实例变量赋值：把原来固定写死的self.wraplength = 180改成self.wraplength = wraplength，这样就会使用你传入的自定义宽度值。

修改后的完整代码 #

""" tk_ToolTip_class101.py gives a Tkinter widget a tooltip as the mouse is above the widget 
tested with Python27 and Python34 by vegaseat 09sep2014 
Modified to include a delay time by Victor Zaccardo, 25mar16
Modified to support custom wraplength by adjusting __init__ parameters
"""
try: # for Python2
    import Tkinter as tk
except ImportError: # for Python3
    import tkinter as tk

class CreateToolTip(object):
    """ create a tooltip for a given widget """
    def __init__(self, widget, wraplength=180, text='widget info'):
        self.waittime = 500 #miliseconds
        self.wraplength = wraplength # 使用传入的自定义宽度，默认180像素
        self.widget = widget
        self.text = text
        self.widget.bind("<Enter>", self.enter)
        self.widget.bind("<Leave>", self.leave)
        self.widget.bind("<ButtonPress>", self.leave)
        self.id = None
        self.tw = None
    
    def enter(self, event=None):
        self.schedule()
    
    def leave(self, event=None):
        self.unschedule()
        self.hidetip()
    
    def schedule(self):
        self.unschedule()
        self.id = self.widget.after(self.waittime, self.showtip)
    
    def unschedule(self):
        id = self.id
        self.id = None
        if id:
            self.widget.after_cancel(id)
    
    def showtip(self, event=None):
        x = y = 0
        x, y, cx, cy = self.widget.bbox("insert")
        x += self.widget.winfo_rootx() + 25
        y += self.widget.winfo_rooty() + 20
        # creates a toplevel window
        self.tw = tk.Toplevel(self.widget)
        # Leaves only the label and removes the app window
        self.tw.wm_overrideredirect(True)
        self.tw.wm_geometry("+%d+%d" % (x, y))
        label = tk.Label(self.tw, text=self.text, justify='left', background="#ffffff", relief='solid', borderwidth=1, wraplength = self.wraplength)
        label.pack(ipadx=1)
    
    def hidetip(self):
        tw = self.tw
        self.tw= None
        if tw:
            tw.destroy()

# testing ...
if __name__ == '__main__':
    root = tk.Tk()
    btn1 = tk.Button(root, text="button 1 (宽250像素)")
    btn1.pack(padx=10, pady=5)
    # 自定义wraplength为250像素
    button1_ttp = CreateToolTip(btn1, 250, \
        'Neque porro quisquam est qui dolorem ipsum quia dolor sit amet, ' 
        'consectetur, adipisci velit. Neque porro quisquam est qui dolorem ipsum ' 
        'quia dolor sit amet, consectetur, adipisci velit. Neque porro quisquam ' 
        'est qui dolorem ipsum quia dolor sit amet, consectetur, adipisci velit.')
    btn2 = tk.Button(root, text="button 2 (默认宽180像素)")
    btn2.pack(padx=10, pady=5)
    # 使用默认的180像素宽度
    button2_ttp = CreateToolTip(btn2, text=\
        "First thing's first, I'm the realest. Drop this and let the whole world " 
        "feel it. And I'm still in the Murda Bizness. I could hold you down, like " 
        "I'm givin' lessons in physics. You should want a bad Vic like this.")
    root.mainloop()

使用说明 #

• 自定义宽度：直接按CreateToolTip(目标控件, 自定义宽度, "提示文本")的格式调用，比如CreateToolTip(btn1, 250, "这是宽250的提示")
• 保留默认宽度：可以省略宽度参数，用关键字指定文本，比如CreateToolTip(btn2, text="默认宽度的提示")，或者直接传180作为第二个参数。

内容的提问来源于stack exchange，提问作者user7722318