Question

I think I am making a design error in my Android app somewhere. My (simplified) code is pasted below.

I am using the writeMidi method in MainActivity. However, I would also like to use it, or actually just trigger it, when “onItemSelected” is triggered in the custom listener.

I am a bit torn on how to do that. Should I redesign this code to fit the customlistener in the main activity?

Thanks for any help.

public class MainActivity extends Activity{


    int song = 0;
    int[] music;
    public int instrument;
    public CustomOnItemSelectedListener listener;


    // *******************************************************
    // set Layout - on create
    // *******************************************************
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        instrument = 0;

        listener = new CustomOnItemSelectedListener();
        addListenerOnSpinnerItemSelection();

        //more stuff, including using the writeMidi method

};


    public void addListenerOnSpinnerItemSelection(){

        instrumentSp = (Spinner) findViewById(R.id.instrument);
        instrumentSp.setOnItemSelectedListener(listener);
    }


    public void writeMidi(int[] music, int count) {
        // so some stff
    }

}

and in a separate file;

public class CustomOnItemSelectedListener implements OnItemSelectedListener {

    private int instrument = 0;

      public void onItemSelected(AdapterView<?> parent, View view, int pos,long id) {
        Toast.makeText(parent.getContext(), 
            "Please wait a minute for the instrument to be changed. ", Toast.LENGTH_SHORT).show();
         instrument = pos;

      }


      public int getInstrument(){
          return instrument;
      }

    }

Answer 1

I tried a number of the solutions suggested, but could get none of them to fully work.

So I solved it by not using a separate class like this:

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