按下后退按钮时破坏活动？

Question

I have an app that allows user to select a txt file from a list and then goes off to the internet to get the contents of that file. All works well except when the user accidentally or deliberately presses the hardware back button to go and see the list again.

Now, when the user clicks a new item from the list (a new file that is), instead of loading a the new file, the app continues off from where it was suspended.I do not want that to happen. I know this is related to the life cycle of the activity.

How do I make sure that it loads the new file rather than continuing from where it left off ?

Answer 1

I suppose you're loading the file in onCreate() . You should do that in onResume() instead.

Do not force Activities to close (eg use finish() ). First, this does not guarantee the Activity will be closed , and second, this is better left to Android to decide.

Answer 2

您可以在活动中覆盖onBackPressed方法，然后调用finish()获得所需的结果。

Answer 3

您只需要通过调用activity.finish（）在onBackPressed（）方法中完成您的活动即可；

Answer 4

To destroy activity on back press, use this code.

@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
     //Destroys activity.
     finish();
}

Answer 5

Another Method to kill an activity is by calling following method.

@Override
public void onBackPressed() {
    super.onBackPressed();
    finish();
}