onCreate flow continues after finish()
android, oncreate
Solution
I'm guessing that it is because finish() doesn't cause the onCreate method to return. You could try simply adding
finish();
return;
Or use an if else
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.layoutb);
if(good data){
//do stuff
}else{
finish();
}
}
Problem
I would like to finish an activity from inside the `onCreate` method. When I call `finish()`, `onDestroy()` is not immediately called, the code keeps flowing past `finish()`. `onDestroy()` isn't called until after the `onCreate()` closing brace. Per the `onCreate()` description at developer.android.com/reference. You can call finish() from within this function, in which case onDestroy() will be immediately called without any of the rest of the activity lifecycle (onStart(), onResume(), onPause(), etc) executing. Reason I ask is: I would like to check data from the Bundle passed to `onCreate()`. Of course I have control of what is passed to `onCreate`, but I still think it should be checked at the point of delivery. My code contains class `A`, which starts Activity `B`. I believe the last two "outside of if clause" tags, shouldn't be called because the `finish` method in the `if` statement should have destroyed the activity. It has nothing to do with the if clause because the tag line after the second `finish()` call is still also read. My Code: Class A ``` @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); // goToBButton: when pressed sends message to class B. Button goToBButton = (Button)this.findViewById(R.id.go_to__b_btn); goToBButton.setOnClickListener(new OnClickListener() { @Override public void onClick (View v) { Log.i(TAG,"A Class: goToBButton, onClick"); Intent i = new Intent(A.this, B.class); startActivityForResult(i,REQ_TO_B); } }); } // end onCreate ``` My Code ClassB ``` public class B extends Activity{ private static final String TAG = "tag"; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.layoutb); // set as true, should always print Tag: one line before first finish" if (true) { Log.i(TAG,"B Class: one line before 1st finish"); finish(); } // shouldn't get here after first finish Log.i(TAG,"B Class: outside of if clause, before second finish"); finish(); // shouldn't get here after second finish Log.i(TAG,"B Class: outside of if clause, after finish"); } // end onCreate @Override public void onStart () { super.onStart(); Log.i(TAG,"B Class: onStart"); } @Override public void onRestart() { super.onRestart(); Log.i(TAG,"B Class: onRestart"); } @Override public void onResume () { super.onResume(); Log.i(TAG,"B Class: onResume"); } @Override public void onPause () { super.onPause(); Log.i(TAG,"B Class: onPause"); } @Override public void onStop () { super.onStop(); Log.i(TAG,"B Class: onStop"); } @Override public void onDestroy () { super.onDestroy(); Log.i(TAG,"B Class: onDestroy"); } } // end B Class ``` Here are the results of my tags: 11-26 15:53:40.456: INFO/tag(699): A Class: goToBButton, onClick 11-26 15:53:40.636: INFO/tag(699): A Class: onPause 11-26 15:53:40.865: INFO/tag(699): B Class: one line before 1st finish 11-26 15:53:40.896: INFO/tag(699): B Class: outside of if clause, before second finish 11-26 15:53:40.917: INFO/tag(699): B Class: outside of if clause, after finish 11-26 15:53:41.035: INFO/tag(699): A Class: onResume 11-26 15:53:41.165: INFO/tag(699): B Class: onDestroy