Android Overriding onBackPressed()

问题

Is it possible to override onBackPressed() for only one activity ?

On back button click I want to call a dialog on a specific Activity, but in all other activities i want it to work as it worked before (going to previous activities).

EDITED

Thank you everyone for your answers, I already had everything like you told me, but my problem was that when i was clicking back button on another Activity, I was going to my previous Activity (The one where i had back button Overridden) and i thought that it wasn\'t working, i thought it was overriding onBackPressed() in whole Application, now i got it.

回答1:

Yes. Only override it in that one Activity with

@Override
public void onBackPressed()
{
     // code here to show dialog
     super.onBackPressed();  // optional depending on your needs
}

don't put this code in any other Activity

回答2:

Override the onBackPressed() method as per the example by codeMagic, and remove the call to super.onBackPressed(); if you do not want the default action (finishing the current activity) to be executed.

回答3:

You may just call the onBackPressed()and if you want some activity to display after the back button you have mention the

Intent intent = new Intent(ResetPinActivity.this, MenuActivity.class);
    startActivity(intent);
    finish();

that worked for me.

回答4:

Just call the onBackPressed() method in the activity you want to show the dialog and inside it show your dialog.

回答5:

Just use the following code with initializing a field

private int count = 0;
    @Override
public void onBackPressed() {
    count++;
    if (count >=1) {
        /* If count is greater than 1 ,you can either move to the next 
        activity or just quit. */
        Intent intent = new Intent(this, SecondActivity.class);
        startActivity(intent);
        finish();
        overridePendingTransition
        (R.anim.push_left_in, R.anim.push_left_out);
        /* Quitting */
        finishAffinity();
    } else {
        Toast.makeText(this, "Press back again to Leave!", Toast.LENGTH_SHORT).show();

        // resetting the counter in 2s
        Handler handler = new Handler();
        handler.postDelayed(new Runnable() {
            @Override
            public void run() {
                count = 0;
            }
        }, 2000);
    }
    super.onBackPressed();
}

回答6:

Best and most generic way to control the music is to create a mother Activity in which you override startActivity(Intent intent) - in it you put shouldPlay=true, and onBackPressed() - in it you put shouldPlay = true. onStop - in it you put a conditional mediaPlayer.stop with shouldPlay as condition

Then, just extend the mother activity to all other activities, and no code duplicating is needed.

回答7:

At first you must consider that if your activity which I called A extends another activity (B) and in both of

them you want to use onbackpressed function then every code you have in B runs in A too. So if you want to separate these you should separate them. It means that A should not extend B , then you can have onbackpressed separately for each of them.

回答8:

Try This Its working

  @Override
public void onBackPressed(){
        super.onBackPressed();
         Intent i=new Intent(Intent.ACTION_MAIN);
        i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
        i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        finish();
}

来源：https://stackoverflow.com/questions/18337536/android-overriding-onbackpressed

标签

android

android-intent

event-handling

overriding