How to change the array source for a spinner? (Android Studio)

Question

I have asked this before, but I was too general.

I have an activity with two radio buttons and only two arrays: String[] tickets; which has 3 items and String[] subscriptions; which has 5 items. By the way, the radio buttons are inside a radioGroup.

The first radioButton is for String[] tickets; and the second radioButton is for String[] subscriptions;

When I check the first radioButton, I want the spinner to be populated by the items in String[] tickets and when I check the second radioButton I want the spinner to be populated by the items in String[] subscriptions;

But how do you do that? I tried using a temporary array which is empty and used it as the array source for the spinner. I would then place one of these arrays inside the empty one. But it did not work.

EDIT:

MainActivity extends AppCompatActivity implements AdapterView.OnItemSelectedListener {

   String[] tickets = {"Ticket #1", "Ticket #2", "Ticket #3"};
   String[] subscriptions = {"Sub #1", "Sub #2", "Sub #3", "Sub #4", "Sub #5"};
   String[] tempArray;
   Spinner spinner1;
   RadioGroup radioGroup;
   RadioButton radioButtonOption;

protected void onCreate(Bundle savedInstanceState) {
   super.onCreate(savedInstanceState);     
   setContentView(R.layout.activity_third);

   radioGroup = (RadioGroup)findViewById(R.id.radioGroup);
   int selectedRadioButton = radioGroup.getCheckedRadioButtonId();
   radioButtonOption = (RadioButton)findViewById(selectedRadioButton);
   spinner1 = (Spinner)findViewById(R.id.spinner1);


   radioButtonOption.setOnClickListener(new View.OnClickListener() {
      @Override
      public void onClick(View v) {
         if (radioButtonOption.getText().equals("Journeys/Tickets")) {
            tempArray = tickets;
         } else if (radioButtonOption.getText().equals("Subscription")) {
            tempArray = subscriptions;
         }
      }
   });

   spinner1.setOnItemSelectedListener(this);
   ArrayAdapter a1 = new ArrayAdapter<>(this, android.R.layout.simple_spinner_item, tempArray);
   a1.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
   spinner1.setAdapter(a1);
   spinner1.setOnItemSelectedListener(this);

Answer 1

Try this

        radioGroup = (RadioGroup)findViewById(R.id.radioGroup);
        spinner1 = (Spinner)findViewById(R.id.spinner1);

        radioGroup.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(RadioGroup group, int checkedId) {
                switch (checkedId)
                {
                    case  R.id.button_1:
                        a1 = new ArrayAdapter<String>(MainActivity.this, android.R.layout.simple_spinner_item ,tickets);
                        spinner1.setAdapter(a1);
                        break;

                    case R.id.button_2:
                        a1 = new ArrayAdapter<String>(MainActivity.this, android.R.layout.simple_spinner_item,subscriptions);
                        spinner1.setAdapter(a1);
                        break;

                }

                a1.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);

            }
        });

        spinner1.setOnItemSelectedListener(this);

Note you need to declare ArrayAdapter a1;