fixing the position of textbox at the bottom of screen

[Mark]

I am creating an app which the textbox have to be fixed at the bottom of screen.

In my app, there is only two components, a text component and a textbox component, the textbox component is below the text component.

however, as the text component has too many words to show, the scroll function of the main screen have to be enabled and allow the user to scroll the screen to read the whole passages. How can I fix the textbox component at the bottom of the screen all the time even the user scroll up/down/the screen? just like the textbox at the bottom of WhatsApp, no matter how you scroll the screen, the textbox keep at the bottom all the time!

many thanks!!

[BodyMindPower]

1. vertical Arragement, height fill parent
put 2 and 3 into 1:
2. vertical scrollArragement, hight=80%
3. vert/horr Arragement, hight=20%
4. Scrollable = false

[Mark]

thanks but if scrollable = false , then how can i scroll the screen and read the whole passage? the passage is very long and the screen must be scrolled to read the whole passage thx

[BodyMindPower]

2. vertical scrollArragement , hight=80% 

you can scroll inside this Arragement 

[Mark]

Thankyou