android - 频繁的 Android 小部件更新

Question

问候，

我正在尝试编写一个显示大纪元时间的时钟小部件，我需要它每秒更新一次。目前我正在使用使用处理程序的服务来执行此操作:

 public class EpochService extends Service {

 private static final String TAG = "EpochService";

 // the time
 private static long mTime;

 // ui components
 private static RemoteViews mViews;
 private static ComponentName mComponent;
 private static AppWidgetManager mManager;

 // handler
 private static Handler mHandler = new Handler();

 @Override
 public void onStart(Intent intent, int id){
  Log.i(TAG, "start");

  // register the receiver
  IntentFilter filter = new IntentFilter();
  filter.addAction(Intent.ACTION_SCREEN_OFF);
  filter.addAction(Intent.ACTION_SCREEN_ON);
  registerReceiver(mIntentReceiver, filter);

  // set up ui
  mViews = new RemoteViews(this.getPackageName(), R.layout.main);
  mManager = AppWidgetManager.getInstance(this);
  mComponent = new ComponentName(this, Clock.class);

  // start
  mHandler.removeCallbacks(mEpochTimerTask);
  mHandler.postDelayed(mEpochTimerTask, 1000);
 }

 @Override
 public void onDestroy(){
  // unregister receiver to prevent memory leak
  mHandler.removeCallbacks(mEpochTimerTask);
  unregisterReceiver(mIntentReceiver);
 }

 @Override
 public IBinder onBind(Intent intent) {
  return null;
 }

 /**
  * The broadcast receiver - handles screen off events to stop drawing
  */
 private static BroadcastReceiver mIntentReceiver = new BroadcastReceiver(){
  @Override
  public void onReceive(Context context, Intent intent) {
   if(intent.getAction().equals(Intent.ACTION_SCREEN_OFF)){
    Log.i(TAG, "stop drawing");
    mHandler.removeCallbacks(mEpochTimerTask);
   }
   else {
    Log.i(TAG, "start drawing");
    mHandler.removeCallbacks(mEpochTimerTask);
    mHandler.postDelayed(mEpochTimerTask, 1000);
   }
  }
 };

 /**
  * Run the Epoch Timer
  */
 private static Runnable mEpochTimerTask = new Runnable(){
  @Override
  public void run() {
   Log.i(TAG, "run");
   mTime = System.currentTimeMillis() / 1000;

   mViews.setTextViewText(R.id.time, Long.toString(mTime));
   mManager.updateAppWidget(mComponent, mViews);
   mHandler.postAtTime(mEpochTimerTask, SystemClock.uptimeMillis() + 1000);
  }
 };

}

我遇到的问题是，随着时间的推移，我的主屏幕似乎变得明显滞后。我是 Android 的新手，所以我不确定我正在做的是否是正确的方法，或者是否有更好的方法来实现这一点(也许使用 AsyncTask？)。有没有一种方法可以频繁更新小部件而不会出现 UI 延迟？如果我需要发布更多代码，请告诉我。我的小部件只是启动和停止此服务，我的 appwidget-provder 有 android:updatePeriodMillis="0"。

在此先感谢您的帮助。

Answer 1

I'm trying to write a clock widget that displays Epoch time and I need it to update every second.

请不要。您的用户会用干草叉攻击您。每秒执行一次远程过程调用会大大降低设备速度并耗尽电池电量。

如果您想要主屏幕上的时钟每秒更新一次，请编写一个自定义主屏幕，这样它就可以在一个进程中完成。

The problem I'm having is that over time, my home screen appears to get noticeably laggy.

这是意料之中的。

Is there a way to update a widget frequently without suffering from UI lag?

没有。默认更新频率是每 30 分钟，而不是每秒。