【代碼】利用Android的Log 演示一個activity的生命週期

代碼：
//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留的小作業 截取LOG

這是演示的結果

//利用LOG展示activity的生命週期  
//註釋表示 中間執行的操作 爲方便的觀察數據，可以在LOGCAT窗口（沒有的話可以在window菜單中的show view中調出）的右側單擊加號創建一個過濾器，我的例子中過濾的是demo

//開始運行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鍵 返回 activity從stack中彈出
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

//再次啓動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鍵 當前TASK 處於後臺轉態，系統保存狀態
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

//再次啓動demo 回覆原來的TASK activity在棧頂
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