How do I make the player only able to move up and down and only with arrows?

I am making a type of Galaga game that is sideways, so I need to know how to move my character only up and down with the arrow keys. I'm new to coding, so this isn't very clear.

If you are doing this on a canvas, then fix the x position and vary the y position of your sprite.

Welcome.

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Creating Animated Apps

Here are some resources to help you learn to use the AI2 tools. A very good way to learn App Inventor is to read the free Inventor's Manual here in the AI2 free online eBook App Inventor 2 Book: Create Your Own Android Apps ... the links are at the bottom of the Web page. The book 'teaches' users how to program with AI2 blocks.

There is a free programming course here Course In A Box and the aia files for the projects in the book are here: App Inventor 2 Book: Create Your Own Android Apps

How to do a lot of basic things with App Inventor are described here: How do you...? .

Also look here App inventor español. Offline. Tutorial. Ejemplos. Instalación. Códigos. Juegos. Curso gratis de App inventor. and here Tutorial Index | imagnity for more tutorials including Imagnity.com List Tutorial, Mirrored - @Saj

Learn about components Component Reference
and visit the Library The MIT App Inventor Library: Documentation & Support Help>Library on the MENU

Create two buttons, and a variable. One button will set the variable to the same variable + 1 and the other btton will set the variable to the same variable -1.


Here is the code that I have
The buttons Down and Up are in a vertical arrangement
And the designer view is here

Read Chapter 17 of the free online book at
http://www.appinventor.org/book2

Thank You!