HandlerThread.getLooper().removeSyncBarrier(token);
HandlerThread.getLooper().getQueue().removeSyncBarrier(token);

import android.os.Handler;
import android.os.HandlerThread;
import android.os.Looper;
import android.os.MessageQueue;

import java.lang.reflect.Method;

/**
* 使用Handler方式实现的预加载
* @author billy.qi
*/
public class PreLoader {

 private int token;
 private Handler mainThreadHandler;//用于将结果处理的task放在主线程中执行
 private HandlerThread handlerThread;//提供一个异步线程来运行预加载任务
 private Handler handler;//预加载使用的handler

 private PreLoader(final Runnable task) {
 mainThreadHandler = new Handler(Looper.getMainLooper());
 handlerThread = new HandlerThread("pre-loader") {
  @Override
  protected void onLooperPrepared() {
  super.onLooperPrepared();
  handler = new Handler();
  handler.post(task);
  //设置同步分割,后面post进来的sync为true的message将暂停执行
  Looper looper = handlerThread.getLooper();
  if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.M) {
   postSyncBarrier(looper.getQueue());
  } else {
   postSyncBarrier(looper);
  }
  }
 };
 handlerThread.start();
 }

 /**
 * 开启预加载
 * 比如:开始网络请求(在HandlerThread中执行)
 * @param task 预加载任务
 */
 public static PreLoader preLoad(Runnable task) {
 return new PreLoader(task);
 }

 /**
 * 处理加载结果, 一般在预加载任务处理完成后调用
 * 由于有handler所在的messageQueue设置了同步分割(SyncBarrier),该task
 * @param task 在主线程中执行的任务
 */
 public void performResultTask(final Runnable task) {
 if (handler != null) {
  handler.post(new Runnable() {
  @Override
  public void run() {
   mainThreadHandler.post(task);
  }
  });
 }
 }

 /**
 * 可以开始执行预加载结果处理
 */
 public void readyToGetData() {
 Looper looper = handlerThread.getLooper();
 if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.M) {
  removeSyncBarrier(looper.getQueue());
 } else {
  removeSyncBarrier(looper);
 }
 }

 private void postSyncBarrier(Object obj) {
 try{
  Method method = MessageQueue.class.getMethod("postSyncBarrier");
  token = (int) method.invoke(obj);
 } catch(Exception e) {
  e.printStackTrace();
 }
 }

 private void removeSyncBarrier(Object obj) {
 try{
  Method method = MessageQueue.class.getMethod("removeSyncBarrier", int.class);
  method.invoke(obj, token);
 } catch(Exception e) {
  e.printStackTrace();
 }
 }

 public void destroy() {
 handlerThread.quit();
 handlerThread = null;
 handler = null;
 mainThreadHandler = null;
 }

}

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.widget.TextView;

public class PreLoaderActivity extends AppCompatActivity {

 private PreLoader preLoader;
 private TextView textView;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
 preLoad();//启动预加载
 //进行页面布局加载及其它初始化工作
 super.onCreate(savedInstanceState);
 setContentView(R.layout.activity_main);
 textView = (TextView)findViewById(R.id.textView);
 //布局初始化完成
 preLoader.readyToGetData();
 }

 private void preLoad() {
 //预加载的任务
 preLoader = PreLoader.preLoad(new Runnable() {
  //将得到的请求结果展示到布局控件上
  @Override
  public void run() {
  //模拟网络请求耗时
  try {
   Thread.sleep(500);
  } catch (InterruptedException e) {
   e.printStackTrace();
  }
  final String result = "result";
  //在UI线程执行的显示任务
  preLoader.performResultTask(new Runnable() {
   //将得到的请求结果展示到布局控件上
   @Override
   public void run() {
   textView.setText(result);
   }
  });
  }
 });
 }

 @Override
 protected void onDestroy() {
 super.onDestroy();
 //在onDestroy()中进行销毁
 preLoader.destroy();
 }
}