在平時(shí)開發(fā)中打開過(guò)三個(gè)activity,分別為：A, B, C，用android設(shè)備中的"back"按鈕，需要點(diǎn)擊三下，才能退出到主界面（即需要三次操作才能銷毀掉這三個(gè)activity）。那么如何只需要點(diǎn)擊一次back就能一次把這三個(gè)activity一次銷毀掉呢，方法挺簡(jiǎn)單的，步驟如下：

（1）創(chuàng)建一個(gè)ActivityCollector.java，此類用作收集和銷毀activity的公共類.

public class ActivityCollector {

    public static List<Activity> activities = new ArrayList<Activity>();

    public static void addActivity(Activity activity) {
        activities.add(activity);
    }

    public static void removeActivity(Activity activity) {
        activities.remove(activity);
    }

    public static void finishAll() {
        for (Activity activity : activities) {
            if (!activity.isFinishing()) {
                activity.finish();
            }
        }
    }

}

(2).創(chuàng)建一個(gè)BaseActivity.java基類,項(xiàng)目中的所有activity都繼承此類.

public class BaseActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        ActivityCollector.addActivity(this);
    }

    @Override
    protected void onDestroy() {
        // TODO Auto-generated method stub
        super.onDestroy();
        ActivityCollector.removeActivity(this);
    }

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(3)讓A, B, C這三個(gè)activity分別去繼承BaseActivity.java.這樣只要activity一起動(dòng),或者子activity中重寫了onDestroy()方法,子activity就會(huì)自動(dòng)的去收集activity,去銷毀某個(gè)Activity.
(4).如何在某個(gè)地方需要一次銷毀所有的activity,只需要調(diào)用ActivityCollector.java中的finishAll()方法.
     比如在app中的任何一個(gè)界面調(diào)用loginout方法,就需要用到一次kill多個(gè)activity:

public void handleMessage(Message msg) {
            super.handleMessage(msg);
            switch (msg.what) {
            case ConstantUtil.LOGINOUT:                
                ActivityCollector.finishAll();
                break;

}

}

上面的代碼很簡(jiǎn)單,但是很適用.