First course on Android

I learned a little about Android last year. This year, I started school and continued to learn about Android development. The first lesson was about layout and use of some listening events. I remember that I did not take it seriously last year, listen carefully this year. Actually, Android is quite interesting ~~

The following is a case study of our first class:

Case Description: In this case, a button event listening function is implemented. The color of the text displayed when you click each button;

Example:

.

. Java code:

==========

Layout file:

<RelativeLayout xmlns: android = ========/> </RelativeLayout>

Download the source code below: Click