public class MainActivity extends Activity {@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);LinearLayout ll = new LinearLayout(this);ll.setOrientation(LinearLayout.VERTICAL);this.setContentView(ll);TextView tv = new TextView(this);tv.setText("Activity为: " + this.toString()+ "\n" + ", Task ID 为:" + this.getTaskId());Button button = new Button(this);button.setText("启动Activity");ll.addView(tv);ll.addView(button);button.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {Intent intent = new Intent(MainActivity.this, SecondActivity.class);startActivity(intent);}});}}public class SecondActivity extends ActionBarActivity {@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);LinearLayout ll = new LinearLayout(this);ll.setOrientation(LinearLayout.VERTICAL);this.setContentView(ll);TextView tv = new TextView(this);tv.setText("Activity为: " + this.toString()+ "\n" + ", Task ID 为:" + this.getTaskId());Button button = new Button(this);button.setText("启动Activity");ll.addView(tv);ll.addView(button);button.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {Intent intent = new Intent(SecondActivity.this,MainActivity.class);startActivity(intent);}});}}
点击第一个activity中的按钮后,会启动第二个activity,在第二个activity中点击按钮,会将第二个activity中弹出,显示出第一个activity.在第一个activity中按下back按键,会直接退出程序,这就说明第二个activity消失了.如果是在第二个activity中按下back键,则会回退到第一个activity中去.
，偶尔，我一个人站在黄昏的荒野，
