Container Stack

Unless an item is a root item, all items need to belong to a valid container. An item's parent is deduced through the following process:

1. If item is a root, no parent needed; finished.
2. Check before keyword, if used skip to 5 using parent of "before" item.
3. Check parent keyword, if used skip to 5.
4. Check container stack, if used skip to 5.
5. Check if parent is compatible.
6. Check if parent accepts.
7. If runtime, add item using runtime methods; finished.
8. If startup, add item using startup methods; finished.

Container items can be manually pushed onto the container stack using :py:func:push_container_stack <dearpygui.dearpygui.push_container_stack> and popped off using :py:func:pop_container_stack <dearpygui.dearpygui.pop_container_stack>.

This process is automated when using :doc:../documentation/container-context-manager. Below is a simple example demonstrating manual stack operations:

.. code-block:: python

import dearpygui.dearpygui as dpg

dpg.create_context()

dpg.push_container_stack(dpg.add_window(label="Tutorial"))

dpg.push_container_stack(dpg.add_menu_bar())

dpg.push_container_stack(dpg.add_menu(label="Themes"))
dpg.add_menu_item(label="Dark")
dpg.add_menu_item(label="Light")
dpg.pop_container_stack()

# remove menu_bar from container stack
dpg.pop_container_stack()

# remove window from container stack
dpg.pop_container_stack()

dpg.create_viewport(title='Custom Title', width=800, height=600)
dpg.setup_dearpygui()
dpg.show_viewport()
dpg.start_dearpygui()
dpg.destroy_context()

Explicit Parental Assignment

Parents can be explicitly assigned using the parent keyword. This is most often used for adding new items at runtime. The above example can be shown again below using explicit parent assignment:

.. code-block:: python

import dearpygui.dearpygui as dpg

dpg.create_context()

dpg.add_window(label="Tutorial", tag="window")

dpg.add_menu_bar(parent="window", tag="menu_bar")

dpg.add_menu(label="Themes", parent="menu_bar", tag="themes")
dpg.add_menu_item(label="Dark", parent="themes")
dpg.add_menu_item(label="Light", parent="themes")

dpg.create_viewport(title='Custom Title', width=800, height=600)
dpg.setup_dearpygui()
dpg.show_viewport()
dpg.start_dearpygui()
dpg.destroy_context()

Context Managers

Context managers can be used to simplify the above example. All the context managers can be found in the :doc:../documentation/container-context-manager but a simple example can be found below:

.. code-block:: python

import dearpygui.dearpygui as dpg

dpg.create_context()

with dpg.window(label="Tutorial"):
    with dpg.menu_bar():
        with dpg.menu(label="Themes"):
            dpg.add_menu_item(label="Dark")
            dpg.add_menu_item(label="Light")
            dpg.add_menu_item(label="Classic")
        
dpg.create_viewport(title='Custom Title', width=800, height=600)
dpg.setup_dearpygui()
dpg.show_viewport()
dpg.start_dearpygui()
dpg.destroy_context()

Benefits

1. Automatically push container to container stack.
2. Automatically pop container off container stack.
3. More structured, readable code.