How to delete an existing menu?

Question

I want to replace an existing menu with an add-on. You can add your own menu with "append" or "prepend", but you want to delete your existing menu and add your own menu.

If you simply empty an existing class as shown below, you can delete the existing menu, but it will continue to output errors to the console.

Delete the top bar menu

bpy.types.TOPBAR_HT_upper_bar.draw = None

Answer 1

bpy.types.TOPBAR_HT_upper_bar.draw expects a draw function. Here is an example for how to replace the built-in draw function with your own:

import bpy

def draw_function(self):
    self.layout.label(text="New Custom Menu")

bpy.types.TOPBAR_HT_upper_bar.draw = draw_function

Answer 2

When I tried a similar method, the def function could not be specified correctly in register.

I learned how to use "lambda s, c: s.layout.separator ()".

Using lambda in register, simply defining an empty function and emptying the menu.

In addition, it was solved by adding the function you want to add with prepend.

´´´Python

import bpy

def IHUSEFUL_HT_menu(self, context):
    self.layout.label(text="foo",icon="NONE")

    return {'FINISHED'}

keep_TOPBAR_HT_upper_bar = bpy.types.TOPBAR_HT_upper_bar.draw

def register():
    lmda = lambda s,c:s.layout.separator()
    bpy.types.TOPBAR_HT_upper_bar.draw = lmda

    bpy.types.TOPBAR_HT_upper_bar.prepend(IHUSEFUL_HT_menu)

def unregister():
    bpy.types.TOPBAR_HT_upper_bar.draw = keep_TOPBAR_HT_upper_bar

if __name__ == "__main__":
    register()

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