How to access widget after being created by add_widget? - python-3.x

Question

When I use add_widget, and try to access it by using ids, I get a key error.
def create_rss(self, *args):
for rss in "food", "wood", "stone", "iron", "gold":
self.ids["res"].add_widget(ToggleButton(id=rss, text=rss))
self.ids["res"].ids[rss].state = "down"
I expected to be able to change the state of the toggle button since it was being done before creating it with add_widget.
When trying to print the parent of the toggle button, I get nothing. So maybe add_widget its not making the togglebuttons the children of "res"?

Answer 1

Question
how can I access the button out side of the for loop?
Solution
There are two methods for the solution.
Method 1 - Create own ids dictionary
This method involves creating our own ids dictionary type property. The advantages of this method are random and sequential access.
Snippets
from kivy.properties import DictProperty
...
class class-name(...):
my_ids = DictProperty({})
def create_rss(self, *args):
for rss in "food", "wood", "stone", "iron", "gold":
toggle_button = ToggleButton(id=rss, text=rss)
self.my_ids[rss] = toggle_button
self.ids["res"].add_widget(toggle_button)
toggle_button.state = "down"
def access_using_my_ids(self):
print(f"\nsequential access:")
for key, value in self.my_ids.items():
print(f"key={key}, value={value}, text={value.text}")
print(f"\nrandom access:")
print(f"object={self.my_ids['stone']}, text={self.my_ids['stone'].text}")
Method 2 - Kivy Widget Tree
This method uses Kivy Widget Tree and a for loop to access the children. The disadvantages of this method is sequential access only.
Snippets
for child in reversed(self.ids.res.children):
if isinstance(child, ToggleButton):
print(f"ToggleButton.text={child.text}")
Kivy ids - created in Python script
Kivy ids created in Python script are not stored in self.ids dictionary type property. Therefore, one will get an error when trying to access it.
Solution
Assign it to a variable.
Snippets
def create_rss(self, *args):
for rss in "food", "wood", "stone", "iron", "gold":
toggle_button = ToggleButton(id=rss, text=rss)
self.ids["res"].add_widget(toggle_button)
toggle_button.state = "down"