Spinner's onItemSelected callback called twice after a rotation if non-zero position is selected

Question

When I create my activity, I setup a Spinner, assigning it a listener and an initial value. I know that the onItemSelected callback is called automatically during a

Answer 1

I am updating @Andres Q.'s answer in Kotlin.

Create an inner class in which you're using Spinner

inner class SpinnerInteractionListener : AdapterView.OnItemSelectedListener, View.OnTouchListener {
        override fun onNothingSelected(parent: AdapterView<*>?) {

        }

        override fun onItemSelected(parent: AdapterView<*>?, view: View?, position: Int, id: Long) {
            if (userSelect) {
                //Your selection handling code here
                userSelect = false
            }
        }

        @SuppressLint("ClickableViewAccessibility")
        override fun onTouch(v: View?, event: MotionEvent?): Boolean {
            userSelect = true
            return false
        }

        internal var userSelect = false
    }

Then declare instance variable outside onCreate() as globally like

lateinit var spinnerInteractionListener: SpinnerInteractionListener

then initialise it inside onCreate() by

spinnerInteractionListener = SpinnerInteractionListener()

and use it like

spinnerCategory.onItemSelectedListener = spinnerInteractionListener
spinnerCategory.setOnTouchListener(spinnerInteractionListener)

here spinnerCategory is Spinner

Answer 2

You can just call to setSelection once you know have the list of items and the position to be selected, in that way you avoid onItemSelected to be called twice.

I've created an article about what I think is a better approach How to avoid onItemSelected to be called twice in Spinners

Answer 3

Managed to find a solution in another stackoverflow question:

spinner.post(new Runnable() {
    public void run() {
        spinner.setOnItemSelectedListener(listener);
    }
});

Answer 4

Try this:

boolean mConfigChange = false;

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    mConfigChange = false;
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_mainf);

    Log.i("SpinnerTest", "Activity onCreate");
    ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this, R.array.colors,
            android.R.layout.simple_spinner_item);
    adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
    ((Spinner) findViewById(R.id.spin)).setAdapter(adapter);

     ((Spinner) findViewById(R.id.spin)).setSelection(2);
    ((Spinner) findViewById(R.id.spin)).setOnItemSelectedListener(this);

}

@Override
protected void onResume() {
    mConfigChange = true;
    super.onResume();
}

@Override
public void onItemSelected(AdapterView<?> spin, View selview, int pos, long selId) {
    if (!mConfigChange)
        Log.i("Test", "spin:" + spin + " sel:" + selview + " pos:" + pos + " selId:" + selId);
    else
        mConfigChange = false;
}

Answer 5

The first time the onItemSelected runs, the view is not yet inflated. The second time it is already inflated. The solution is to wrap methods inside onItemSelected with if (view != null).

@Override
public void onItemSelected(AdapterView<?> parent, View view, int pos, long id) {
    if (view != null) { 
        //do things here

    }
}

Answer 6

This is what i did:

Do a local variable

Boolean changeSpinner = true;

On the saveInstanceMethod save the selected item position of the spinner

@Override
public void onSaveInstanceState(Bundle outState) {
    super.onSaveInstanceState(outState);
    outState.putInt("ItemSelect",mySpinner.getSelectedItemPosition());
}

Then on the activity created get that int from savedInstanceState and if the int is != 0 then set the boolean variable on false;

@Override
    public void onActivityCreated(Bundle savedInstanceState) {

    if (savedInstanceState!=null) {
        if (savedInstanceState.getInt("ItemSelect")!=0) {
           changeSpinner = false;
        }
    }

}

And for last on the OnItemSelected from the spinner do this

mySpinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
    public void onItemSelected(AdapterView<?> parent,android.view.View v, int position, long id) {
        if (changeSpinner) {
           [...]
        } else {
           changeSpinner= true;
        }
    });

So, the first time when is called is not going to do anything, just make the boolean variable true, and the second time is going to execute the code. Maybe not the best solution but it work.