Activity界面

@Overridepublic void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    // Get the message from the intent    Intent intent = getIntent();    String message = intent.getStringExtra(MyFirstActivity.EXTRA_MESSAGE);    // Create the text view    TextView textView = new TextView(this);    textView.setTextSize(40);    textView.setText("Hello World");    setContentView(textView);
}