asynctask源码解析

public final AsyncTask<Params, Progress, Result> (Params... params) {
       return executeOnExecutor(sDefaultExecutor, params);
   }

public final AsyncTask<Params, Progress, Result> executeOnExecutor(Executor exec,
           Params... params) {
       ...
       mStatus = Status.RUNNING;
       onPreExecute();
       mWorker.mParams = params;
       exec.execute(mFuture);
       return this;
   }

mWorker = new WorkerRunnable<Params, Result>() {
          public Result call() throws Exception {
              mTaskInvoked.set(true);

              Process.setThreadPriority(Process.THREAD_PRIORITY_BACKGROUND);
              
              Result result = doInBackground(mParams);
              Binder.flushPendingCommands();
              return postResult(result);
          }
      };

      mFuture = new FutureTask<Result>(mWorker) {
          
          protected void done() {
          	postResultIfNotInvoked(get());
          }
      };