【代码】利用Android的Log 演示一个activity的生命周期

代码：
//DemoActivity.java

package uni.activity;
/*
 @author octobershiner
 2011 7 22
 SE.HIT
*/
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;

public class ActivityDemoActivity extends Activity {
    /** Called when the activity is first created. */
    
    private static final String TAG = "demo";
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        Log.d("demo", "this is a test string ");
    }

    protected void onStart(){
        super.onStart();
        Log.i(TAG, "The activity state---->onStart");
    }
    
    protected void onRestart(){
        super.onRestart();
        Log.i(TAG, "The activity state---->onReatart");
    }

    protected void onResume(){
        super.onResume();
        Log.i(TAG, "The activity state---->onResume");
    }

    protected void onPause(){
        super.onPause();
        Log.i(TAG, "The activity state---->onPause");
    }

    protected void onStop(){
        super.onStop();
        Log.i(TAG, "The activity state---->onStop");
    }

    protected void onDestroy(){
        super.onDestroy();
        Log.i(TAG, "The activity state---->onDestroy");
    }

    
}

演示sundy留的小作业 截取LOG

这是演示的结果

//利用LOG展示activity的生命周期
//注释表示 中间执行的操作 为方便的观察数据，可以在LOGCAT窗口（没有的话可以在window菜单中的show view中调出）的右侧单击加号创建一个过滤器，我的例子中过滤的是demo

//开始运行demo
07-22 11:18:19.311: INFO/demo(281): The activity state---->onStart
07-22 11:18:19.311: INFO/demo(281): The activity state---->onResume

//按下了back键 返回 activity从stack中弹出
07-22 11:18:34.821: INFO/demo(281): The activity state---->onPause
07-22 11:18:35.090: INFO/demo(281): The activity state---->onStop
07-22 11:18:35.090: INFO/demo(281): The activity state---->onDestroy

//再次启动demo
07-22 11:18:45.550: INFO/demo(281): The activity state---->onStart
07-22 11:18:45.550: INFO/demo(281): The activity state---->onResume

//按下了HOME键 当前TASK 处于后台转态，系统保存状态
07-22 11:18:53.750: INFO/demo(281): The activity state---->onPause
07-22 11:18:54.820: INFO/demo(281): The activity state---->onStop

//再次启动demo 回复原来的TASK activity在栈顶
07-22 11:19:03.550: INFO/demo(281): The activity state---->onReatart
07-22 11:19:03.550: INFO/demo(281): The activity state---->onStart
07-22 11:19:03.550: INFO/demo(281): The activity state---->onResume