当在 Tkinter 中没有输入的情况下取消选择输入字段时，使占位符重新出现

如何解决当在 Tkinter 中没有输入的情况下取消选择输入字段时，使占位符重新出现

当用户在 Tkinter/python 中没有放入任何东西但点击离开时，我试图让占位符重新出现在条目小部件中。 请帮忙。

def windturbineHeightClear(event):

    windturbineHeight.delete(1,'end')

windturbineHeight = tk.Entry(window,width=10)
windturbineHeightPlaceholder = ' Height'
windturbineHeight.insert(0,windturbineHeightPlaceholder)
windturbineHeight.bind("<Button-1>",windturbineHeightClear)
windturbineHeight.place(x=320,y=108,width=320,height=34)city.place(x=320,height=34)

解决方法

您必须绑定到用户点击远离条目并检查它是否为空。如果为空，则插入占位符文本。

这是工作代码：

import tkinter as tk


def when_unfocused(event):
    text_in_entry = windTurbineHeight.get() # Get the text
    if text_in_entry == "": # Check if there is no text
        windTurbineHeight.insert(0,windTurbineHeightPlaceholder) # insert the placeholder if there is no text

def windTurbineHeightClear(event):
    windTurbineHeight.delete(0,'end') # btw this should be 0 instead of 1


window = tk.Tk()
windTurbineHeight = tk.Entry(window,width=10)


windTurbineHeightPlaceholder = 'Height'
windTurbineHeight.insert(0,windTurbineHeightPlaceholder)
windTurbineHeight.bind("<FocusOut>",when_unfocused) # When the user clicks away
windTurbineHeight.bind("<FocusIn>",windTurbineHeightClear) # When the user clicks on the entry

windTurbineHeight.pack()

window.mainloop()