OnItemSelectedListener Spinner Recreate loop - Android

Question

I have a spinner and when an item is selected i want to recreate the activity. But when the activity is recreated it keeps constantly recreating because the new itemSelectedListener is triggered. I have fixed the bug but i am interested in why this is happening. Thank you in advance for any insights you offer.

    sp_lang.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
               recreate();
        }
        @Override
        public void onNothingSelected(AdapterView<?> parent) {
        }
    });

First of all, show us you recreate() code. Also, why you want to achieve something like this? — Shermano, Jun 26 '19 at 14:30
If you call setSelection() of the Spinner. That will trigger the recreate() everytime. — reixa, Jun 26 '19 at 14:32
i dont use getSelection and i am aware that could happen. I dont have a recreate code. Do i need one i just let android handle it. Is that wrong? — Chris Papantonis, Jun 26 '19 at 14:54

Jaime Suarez · Accepted Answer · 2019-06-27T09:37:43.917

You can avoid the first event with a flag in the OnItemSelectedListener.

sp_lang.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {

        Boolean firstEventConsumed = false;

        @Override
        public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
               if (firstEventConsumed) {
                   recreate();
               } else {
                   firstEventConsumed = true;
               }
        }
        @Override
        public void onNothingSelected(AdapterView<?> parent) {
        }
    });

EDIT

I have found a solution but it is just a workaround. It is not a definitive solution.

It has a strange behaviour when you recreate the activity. When the activity is created for the first time, it doesn't call twice the onItemSelected, but when it is recreated it is called twice.

What I have done below is to control when the item is selected by the user (handling the touch event) and when it is done by the activity.

public class MainActivity extends AppCompatActivity {

    private Boolean isUserAction = false;

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);


        // get the spinner
        // create the adapter
        spinner.setAdapter(spinnerAdapter);
        spinner.setOnTouchListener(new View.OnTouchListener() {
            @Override
            public boolean onTouch(View view, MotionEvent motionEvent) {
                isUserAction = true;
                return false;
            }
        });
        spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
                if (isUserAction) {
                    recreate();
                }
            }

            @Override
            public void onNothingSelected(AdapterView<?> adapterView) {
                // do nothing
            }
        });
    }
}

There is nothing more rly. I just use findViewById, then i put data on spinner and add the listener. — Chris Papantonis, Jun 27 '19 at 08:25
@ChrisPapantonis I have updated my answer. Please, check it out. — Jaime Suarez, Jun 27 '19 at 09:38
Very elegant. I didnt know why this was happening while testing i figure it out. I used a similar approach too. — Chris Papantonis, Jun 29 '19 at 05:29

OnItemSelectedListener Spinner Recreate loop - Android

1 Answers1