Question

Just started checking out android development, but having problems already. The activity shuts down when button bConvert is pressed. The outputValue.setText is apparently used wrong. Whats up? Thank you for help! 🙂

public class StartingPoint extends Activity {
    TextView outputValue;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        initialize();
    }

    private void initialize() {
        Button bConvert = (Button) findViewById(R.id.bConvert);
        EditText inputValue = (EditText) findViewById(R.id.etInput);
        TextView outputValue = (TextView) findViewById(R.id.userOutput);
        bConvert.setOnClickListener(convertHandler);
    }

    View.OnClickListener convertHandler = new View.OnClickListener() {
        public void onClick(View v) {
            // TODO Auto-generated method stub
            outputValue.setText("Fahrenheit: "+ 100);
        }
    };

    private float convert(float celsius) {
        return ((celsius*9/5)+32);
    }
}

Answer 1

Replace the TextView outputValue = (TextView) findViewById(R.id.userOutput); line with

outputValue = (TextView) findViewById(R.id.userOutput);