如何在 Android 中为 Spinner 设置所选项目

Question

In an Android app, I have a SpinnerAdapter that I am using to display expiration years of credit cards. My variable expirationYears contains an array of Strings with years from "2020" to "2029" . It was declared as String[] expirationYears = new String[10]; and then with a function I set the ten years as Strings, from current year and then the nine subsequent years after that for a total of ten elements in the array. When I run it, this is what I see:

Everything is perfect so far. The only problem is that when as you see in the image above, 2020 is the year selected by default. That is the first element in the expirationYears array. But I want to set 2021 as default (the second element of the array). This is what my code has:

Spinner spinnerYearCreditCardPayment;
SpinnerAdapter creditCardYearAdapter = new SpinnerAdapter(Payment.this, expirationYears);
creditCardYearAdapter
    .setDropDownViewResource(android.R.layout.spinner_dropdown_item);
spinnerYearCreditCardPayment.setAdapter(creditCardYearAdapter);
spinnerYearCreditCardPayment
    .setOnItemSelectedListener(new OnItemSelectedListener() {
        ..........
    });

I was expecting to have some property available to define which element I want to show by default. Something like creditCardYearAdapter.setSelectedItem(INDEX_NUMBER) . But that property does not exist. Do you know how I could set the default selected item so that it is not the first element of the array (2020) but the second (2021)? Thank you.

UPDATE 1:

Following The_Martian's answer, this was what I did:

spinnerYearCreditCardPayment
    .setOnItemSelectedListener(new OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> arg0, View arg1, int arg2, long arg3) {
           arg0.setSelection(1);
           cardYear = (String) spinnerYearCreditCardPayment
               .getSelectedItem();
        }
        @Override
        public void onNothingSelected(AdapterView<?> arg0) {
            // TODO Auto-generated method stub
        }
    });

Now I correctly see the second element of the array ("2021") as the default selection.

The problem is that when I use arg0.setSelection(1); , I choose another year and it does not respond. The selected year remains "2021" even thought I am trying to change the year.

Answer 1

You can do similar to the following. I am just giving you an idea here.

spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
                 parent.setSelection(position + 1);  
            }

            @Override
            public void onNothingSelected(AdapterView<?> parent) {

            }
        });

Answer 2

Try this snippet

  spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() 
    {
       public void onItemSelected(AdapterView<?> parent, View view, int pos, long id) 
         {

               int seleccion=parent.getSelectedItemPosition();
                spinner.setSelection(position)
        });
    }

Answer 3

You can select the spinner item based on value instead of position. Can refer the example below-

String value = "to be selected value";
ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this, R.array.select_state, android.R.layout.simple_spinner_item);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
mSpinner.setAdapter(adapter);
if (value != null) {
    int spinnerPosition = adapter.getPosition(value);
    mSpinner.setSelection(spinnerPosition);
}