How to get the list/tree of all the controls added to the page and how to get access to one of them

Question

I developed a simple app with Flet Python. The app contains some controls such as text and buttons organized in rows and columns. Here is my code:

import flet as ft

def main(page: ft.Page):
    def Next_Image(e):
        print(page.controls)        

    # CONTROLS DESIGN
    cont = ft.Container(bgcolor=ft.colors.AMBER,
                    border=ft.border.all(3, ft.colors.RED),
                    width=250,
                    height=600,
                    )

    button_previous_img = ft.IconButton(icon=ft.icons.ARROW_CIRCLE_LEFT, tooltip='Previous Image')
    button_next_img = ft.IconButton(icon=ft.icons.ARROW_CIRCLE_RIGHT, tooltip='Next Image', on_click=Next_Image)
    text_num_img = ft.Text(value="DOC")

    # ADD CONTROLS TO THE PAGE
    page.add(
        ft.Column(
            [
                cont,
                ft.Row(
                    [
                        button_previous_img,
                        text_num_img,
                        button_next_img
                    ],
                    alignment=ft.MainAxisAlignment.CENTER,
                )
            ],
            horizontal_alignment = ft.CrossAxisAlignment.CENTER,
        )

    )
    page.update()


ft.app(target=main)

I would like to retrieve the whole tree of children controls added to the page pressing a button. I'm able to display only the outmost control, specifically the column. Moreover, I would like to access to a control, let's say the container 'cont' inside the button event 'Next_Image()'. Is there a way to access to him with the name variable or with its index within the controls collection? Such as:

cont = page.controls["cont"] # with the variable name
cont = page.controls["4"] # with the variable index (assuming it's 4)

Answer 1

If you want tree of controls you can use this:

    def get_tree(controls, indent=""):

        indent = indent + "\t"

        for con in controls:
            print(f"{indent}{con._get_control_name()}")
            if hasattr(con, 'controls'):
                if len(con.controls) > 0:
                    get_tree(con.controls, indent)
            elif hasattr(con, 'content'):
                if hasattr(con.content, 'controls'):
                    if len(con.content.controls) > 0:
                        get_tree(con.content.controls, indent)
            else:
                continue

    get_tree(page.controls)

Code goes thru controls print them and print their children and go deeper etc.

For getting control by index you can you use cont = page.controls[0].controls[0] if you want get cont. By page.controls[0] you get in to ft.Column and then you want children of ft.Column so you use page.controls[0].controls[0] and you have what you want