Frame loosing height when filled tkinter

问题

Hello everyone i am learning to make a gui with tkinter but i run into something and can't find the answer to it i have 3 frames a header a shadow for the header and a main content frame and that works fine

code :

root = Tk()
root.geometry("1080x600")
root.minsize(width=1080, height=600)
root.maxsize(width=1080, height=600)
root.title("learning ui")

headerFrame = Frame(root, height=50, bg="#17181b")
headerShadow = Frame(root, height=3, bg="#08090a")
contentFrame = Frame(root, bg="#17181b")

headerFrame.pack(side=TOP, fill=X)
headerShadow.pack(fill=X)
contentFrame.pack(fill=BOTH, expand=True)

root.mainloop()

Screen shot :

But when i pack something to the header it looses its height.

code:

root = Tk()
root.geometry("1080x600")
root.minsize(width=1080, height=600)
root.maxsize(width=1080, height=600)
root.title("learning ui")

headerFrame = Frame(root, height=50, bg="#17181b")
headerShadow = Frame(root, height=3, bg="#08090a")
contentFrame = Frame(root, bg="#17181b")

headerFrame.pack(side=TOP, fill=X)
headerShadow.pack(fill=X)
contentFrame.pack(fill=BOTH, expand=True)

main.e = Entry(headerFrame)
main.e.pack(side=RIGHT)
main.e.focus_set()

searchBtn = Button(headerFrame, text="Search", command=lambda: callback(retrieve_input()))
searchBtn.pack(side=RIGHT)

def callback(q):
    print q

root.mainloop()

Screen shot:

回答1:

All widgets are designed to "shrink to fit" their children. While this may seem counter-intuitive at first, it's the best way to do widget layout. Don't try to force a frame or window to be a specific size, just put the widgets in that you want and it will end up being the right size.

If you want to turn this feature off you can, but I strongly recommend against it. If you want to know more, search for "overrideredirect".

来源：https://stackoverflow.com/questions/31234682/frame-loosing-height-when-filled-tkinter