I have the following code in python:

from kivy.app import App
from kivy.uix.widget import Widget
class UI(Widget):
 pass

class UIApp(App):
 def build(self):
 return UI()

 def process(self):
 text = self.ids.input.text
 print(text)

and in UI.kv:

#:kivy 1.0.9

<UI>:
 title: 'InputDialog'
 auto_dismiss: False
 id: 'test1'

 RelativeLayout:
 orientation: 'vertical'
 pos: self.pos
 size: root.size
 id: 'test2'

 TextInput:
 id: 'input'
 hint_text:'Enter compounds'
 pos_hint: 'center_x': 0.5, 'center_y': 0.705
 size_hint: 0.95, 0.5

now if I call process() I get the error 'UIApp' object has no attribute 'ids'. Alright. Now I try replacing self with UI: AttributeError: 'kivy.properties.DictProperty' object has no attribute 'input'. Trying to adress 'test1' also didn't help, neither did removing the ' around the ids in the .kv file.

Is there a way to get the input from the field without creating this field programatically?

Problem

In your kv file, you have defined id as string.

Kivy » Referencing Widgets

Warning

When assigning a value to id, remember that the value isn’t a string.
There are no quotes: good -> id: value, bad -> id: 'value'

Solution

1. In your kv file, remove single quotes from all the id
   


2. In your Python script, replace self.ids.input.text with self.root.ids.input.text because the ids were defined under the root, class UI()
   

Example

kv file

#:kivy 1.0.9

<UI>:
 title: 'InputDialog'
 auto_dismiss: False
 id: test1

 RelativeLayout:
 orientation: 'vertical'
 pos: self.pos
 size: root.size
 id: test2

 TextInput:
 id: input
 hint_text:'Enter compounds'
 pos_hint: 'center_x': 0.5, 'center_y': 0.705
 size_hint: 0.95, 0.5
 on_text: app.process()

main.py

from kivy.app import App
from kivy.uix.widget import Widget
from kivy.lang import Builder


Builder.load_file('main.kv')


class UI(Widget):
 pass


class UIApp(App):
 def build(self):
 return UI()

 def process(self):
 text = self.root.ids.input.text
 print(text)


if __name__ == "__main__":
 UIApp().run()

Output