title: setText use resource for placeholder
body: <p>Following the instruction in Android Boot Camp to make an app for buying concert tickets.(very basic) My code is exacatly the same as the book.
  At the end of the code the user inputs how many tickets they want and it should output the cost of the tickets for the group they picked. The last line is where I'm running into problems. I don't understand why it's not working and I haven't found anything that explains why this is wrong and how to fix it.</p>
  
  <p>I've looked at the linked answer to see if it helped but it does not.</p>
  
  <p>The following code is from MainActivity.java</p>
  
  <pre><code>    public class MainActivity extends AppCompatActivity {
  double costPerTicket = 79.99;
  int numberOfTickets;
  double totalCost;
  String groupChoice;
  
  @Override
  protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);
      final EditText tickets = (EditText)findViewById(R.id.txtTickets);
      final Spinner group = (Spinner)findViewById(R.id.txtGroup);
      Button cost = (Button)findViewById(R.id.btnCost);
      cost.setOnClickListener(new View.OnClickListener() {
          final TextView result = ((TextView)findViewById(R.id.txtResult));
  
          @TargetApi(Build.VERSION_CODES.N)
          @Override
          public void onClick(View v) {
              numberOfTickets = Integer.parseInt(tickets.getText( ).toString( ));
              totalCost = costPerTicket * numberOfTickets;
              DecimalFormat currency = new DecimalFormat("$###,###.##");
              groupChoice = group.getSelectedItem( ).toString( );
              result.setText("Cost for " + groupChoice + "is " + currency.format(totalCost));
  
          }
      }
      );
  
  }
  </code></pre>
  
  <p>}</p>