how to use pack() method to center element in a LabelFrame in tkinter

I defined a LabelFrame as a parent for some elements, I defined the width and the height of the LabelFrame and i set pack_propagate to 0

        self.parent.grid_rowconfigure(0, weight=1)
        self.parent.grid_columnconfigure(0, weight=1)
        self.parent.grid_rowconfigure(1, weight=1)
        self.parent.grid_columnconfigure(1, weight=1)

 # Déclaration des elements de "Tag NFC"
        self.tag_label = tk.LabelFrame(self.parent, text="Tag NFC",height=200,width=280,bg=self.background_color ,font=self.title_font)
        self.tag_label.grid(column=0,row=0,ipadx=10,ipady=10,padx=10,pady=10)
        self.tag_label.pack_propagate(0)
        
        self.uid_entry_label= tk.Label(self.tag_label, text="ID Utilisateur",bg=self.background_color,font=self.content_font)
        # self.uid_entry_label.grid(column= 0, row=0 )
        self.uid_entry_label.pack()
        
        self.uid_entry =  tk.Spinbox(self.tag_label,font=self.content_font)
        # self.uid_entry.grid(column= 0, row=1 )
        self.uid_entry.pack()
        
        self.key_entry_label= tk.Label(self.tag_label, text="Clé de chiffrement",bg=self.background_color,font=self.content_font)
        # self.key_entry_label.grid(column= 0, row=2 )
        self.key_entry_label.pack()
        
        self.key_entry = ttk.Combobox(self.tag_label,font=self.content_font)
        # self.key_entry.grid(column=0, row=3 )
        self.key_entry.pack()

but when i pack my content, the content in the label frame dont use the height of its

I want to spread the element equally across the height of the frame

Is it possible ?

A solution I tend to use is creating "container" Frames for groups of widgets, which makes the overall packing behavior more predictable.

Here, I've created two new Frames, top_items and bottom_items, and set their pack parameters to center them in the LabelFrame

self.top_items = tk.Frame(self.tag_label, bg=self.background_color)
self.top_items.pack(expand=True, fill='x')

self.uid_entry_label = tk.Label(self.top_items, text="ID Utilisateur",bg=self.background_color,font=self.content_font)
self.uid_entry_label.pack()

self.uid_entry = tk.Spinbox(self.top_items,font=self.content_font)
self.uid_entry.pack()

self.bottom_items = tk.Frame(self.tag_label, bg=self.background_color)
self.bottom_items.pack(expand=True, fill='x')

self.key_entry_label = tk.Label(self.bottom_items, text="Clé de chiffrement",bg=self.background_color,font=self.content_font)
self.key_entry_label.pack()

self.key_entry = ttk.Combobox(self.bottom_items,font=self.content_font)
self.key_entry.pack()

Note that the master/parent of the _label and _entry widgets has changed accordingly!

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As an aside, the second label/field looks a little too low to my eye. If you want to nudge it upwards a bit, you can add some y padding to the bottom side of the bottom_items Frame like this:

self.bottom_items.pack(expand=True, fill='x', pady=(0, 30))

> but when i pack my content, the content in the label frame dont use
> the height of its.

> I want to spread the element equally across the height of the frame
>
> Is it possible ?

• You don't need grid_rowconfigure and grid_columnconfigure. It doesn't
  affect anything.
• You don't need to specify height=200,width=280. The
  tag_label.pack_propagate will handle.
• Set the tag_label.pack_propagate index to 1 instead of zero.
• You can use pack() or grid(). It is up to you. As for me, I use pack().

Code:

self.tag_label = tk.LabelFrame(self.parent, text="Tag NFC",  bg=self.background_color)
self.tag_label.pack()
# self.tag_label.grid(column=0,row=0,ipadx=10,ipady=10,padx=10,pady=10)
self.tag_label.pack_propagate(1)

Screenshot: