Learning Java by Building Android  Games
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Using Java packages

Packages are grouped collections of classes. If you look at the top of the code that we have written so far, you will see these lines of code.

import android.app.Activity;
import android.os.Bundle;

These lines of code make available the Activity and Bundle classes as well as their methods. Comment out the above two lines like this:

// import android.app.Activity;
// import android.os.Bundle;

Now look at your code and you will see errors in at least three places. The word Activity has an error because Activity is a class which Android Studio no longer is aware of in the following line:

public class SubHunter extends Activity {

The word onCreate also has an error because it is a method from the Activity class and the word Bundle has an error because it is a class which since we commented out the previous two lines Android is no longer aware of. This next line highlights where the errors are.

protected void onCreate(Bundle savedInstanceState) {

Uncomment the two lines of code two resolve the errors and we will add some more import… code for the rest of the classes we will use in this project including one to fix the MotionEvent error.