@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    setListAdapter(new ArrayAdapter<String>(this, R.layout.row,R.id.label,items));

    view = this.getWindow().getDecorView();
    view.setBackgroundResource(R.color.white);
}


public void onListItemClick(ListView parent, View v, char position, long id) {
    String s = label.getText().toString();
    double l = Double.parseDouble(s);
    double o;
    switch (position) {
        case 0:
            view.setBackgroundResource(R.color.red);
            break;
        case 1:
            view.setBackgroundResource(R.color.green);
            break;
        case 2:
            view.setBackgroundResource(R.color.white);
            break;
        case 3:
            view.setBackgroundResource(R.color.orange);
            break;

    }
}