监听Activity进入后台(最小化),并根据时间判断是否超时,此解决办法可用于超时重登陆

通过重写一个继承自Activity的基类中的onUserLeaveHint()方法,当用户按Home键等操作使程序进入后台时即开始计时,当用户使程序恢复为前台显示时执行onResume()方法,在其中判断是否超时.

public class BaseActivity extends Activity {    private static final String TAG = "z";    private static SharedPreferences pref;    private static boolean isLeave = false;    public OfficeBaseActivity() {        super();        // TODO Auto-generated constructor stub    }        @Override    protected void onCreate(Bundle savedInstanceState) {        // TODO Auto-generated method stub        super.onCreate(savedInstanceState);        pref = getSharedPreferences("timeoutcheck", Context.MODE_PRIVATE);    }    @Override    protected void onUserLeaveHint() { //当用户按Home键等操作使程序进入后台时即开始计时        // TODO Auto-generated method stub        super.onUserLeaveHint();        if(!isLeave){            isLeave=true;            saveStartTime();        }    }        @Override    protected void onResume() { //当用户使程序恢复为前台显示时执行onResume()方法,在其中判断是否超时.        // TODO Auto-generated method stub        super.onResume();        if(isLeave){            isLeave=false;            timeOutCheck();        }    }    public void timeOutCheck() {        long endtime = System.currentTimeMillis();        Log.i(TAG, "endtime  == " + endtime);        Log.i(TAG, "starttime  == " + getStartTime());        Log.i(TAG, "endtime - getStartTime == " + (endtime - getStartTime()));        if (endtime - getStartTime()>= 30 * 1000){            Toast.makeText(this, "超时了", Toast.LENGTH_SHORT).show();        }    }    public void saveStartTime() {        pref.edit().putLong("starttime", System.currentTimeMillis()).commit();    }    public long getStartTime() {        return pref.getLong("starttime", 0);    }}