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Android Build an Interactive Story App (Retired) Intents and Multiple Activities Adding a Second Activity

Posted by Zachary Blasczyk
Zachary Blasczyk
723 Points

Validation of Fields

If the mNameField field is empty and I try to parse it to the name field below (Clicking the button); my app crashes because of a "null" value. null pointer exception.

How would I encapsulate the activity it in a Try Catch or validation of some kind?

public class MainActivity extends AppCompatActivity { private EditText mNameField; private Button mStartButton;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    mNameField = (EditText) findViewById(R.id.nameEditText);
    mStartButton = (Button) findViewById(R.id.startButton);
    mStartButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            String Name = mNameField.getText().toString();
            startStory();
        }
    });
}
private void startStory()
{
    Intent intent = new Intent(this, StoryActivity.class);
    startActivity(intent);
}}