Writing our first Java code
So, we now know the code that will output to logcat or the user's screen. But where do we put the code? To answer this question, we need to understand that the
onCreate method in
HelloWorldActivity.java executes as the app is preparing to be shown to the user. So, if we put our code at the end of this method, it will run just as the user sees it. Sounds good.
We know that to execute the code in a method, we need to call it. We have wired our buttons up to call a couple of methods,
bottomClick. Soon, we will write these methods. But who or what is calling
onCreate? The answer to this mystery is that Android itself calls
onCreate in response to the user clicking the app icon to run the app. In Chapter 6 ...