How to set onBackPressed in Second Activity

Question

I set the <button> in activity_main.xml

<Button
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:onClick="ReturnHome"
    android:text="Go Back"
    android:layout_marginBottom="79dp"
    android:layout_alignParentBottom="true"
    android:layout_alignParentRight="true"
    android:layout_alignParentEnd="true" />

And now I'd like to add onBackPressed method in AnswerActivity

public class AnswerActivity extends AppCompatActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_answer);
    TextView textViewDisplayResult = (TextView) findViewById(R.id.text_view_display_result);

To be able to go back to previous page which is Fragment.

Can somebody guide me step by step how to do it?

Edit:

I wrote something like this

     super.onBackPressed();
        Intent returnIntent = new Intent();
        finish();

But it says 'variable "returnIntent" is never used'. How to fix it?

Show us what did you try and please be more specific – Basil Battikhi May 14 '17 at 15:21 — Basil Battikhi, May 14 '17 at 15:21
where are you adding fragment? show that code – N J May 14 '17 at 15:28 — N J, May 14 '17 at 15:28
@NJ, please explain more, what do you mean – Ramona May 14 '17 at 15:44 — Ramona, May 14 '17 at 15:44

Zoe · Accepted Answer · 2018-01-31T21:39:18.103

0

If you meant the physical button on the device, this is done by overriding:

@Override
public void onBackPressed() {
    FragmentManager fm = getActivity().getSupportFragmentManager();
    fm.popBackStack();
}

And your code:

super.onBackPressed();
    Intent returnIntent = new Intent();
    finish();

Shows returnIntent is never shown because you never called startActivity (intent). And you have to make sure you add a target.

edited Jan 31 '18 at 21:39

answered May 14 '17 at 15:32

Zoe

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did you read the question properly? OP want to go to the previous fragment. – N J May 14 '17 at 15:35
Clearly the question was clear. Though he want to go to previous fragment on onBackPressed but he still shows us xml code for Button – Swarnveer May 14 '17 at 15:36
@Swarnveer, so what 'she' :) can show you to be more specific and clear? – Ramona May 14 '17 at 15:41
Sorry for "he" I didn't knew. And earlier I meant, "the question wasn't clear". It was was a type – Swarnveer May 14 '17 at 15:46
@Swarnveer, no problem at all :) Just please help me if you can. – Ramona May 14 '17 at 15:57
@LunarWatcher. I appreciate your efforts. It is as you said a `physical button` and your second option is a good way to follow. But what to write inside this method `onBackPressed`? – Ramona May 14 '17 at 16:05
You need to override onBackPressed using Ctrl + O – Swarnveer May 14 '17 at 17:28
I didn't understand what is the Button for when you want things to be done in onBackPressed – Swarnveer May 14 '17 at 17:28
@Swarnveer the xml with the button threw me off, first OP says (s)he wants to use onBackPressed while showing XML code for a .xml button. I showed both solutions as it is very hard to understand which OP wanted to achieve. – Zoe May 14 '17 at 19:55
@Ramona You use this code: `FragmentManager fm = getActivity().getSupportFragmentManager(); fm.popBackStack();` – Zoe May 14 '17 at 19:56
@LunarWatcher. Many thanks Lunar. Tell me please how to 'add this target'? I get now `getActivity` in red. – Ramona May 14 '17 at 20:19
That is from a fragment. If you call it from an activity remove getActivity – Zoe May 15 '17 at 13:29
Many thanks Lunar. Could you please have a look at my other issue?http://stackoverflow.com/questions/43945129/getting-constant-false-value-from-method – Ramona May 15 '17 at 14:29
@LunarWatcher. Hi Lunar. Just came accross your answer and thought maybe you would be able to help with this issue..https://stackoverflow.com/questions/43997655/zoom-in-out-the-whole-page-layout. Many thanks in advance. – Ramona May 16 '17 at 09:51
@Ramona looking at both those questions. But if this answer worked for you, please mark it as the solution(to let others know this problem is answered and solved) – Zoe May 16 '17 at 15:47

How to set onBackPressed in Second Activity

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