android asynctask的fragment更新UI（附线程管理）

package com.asynctask.sample.task; import android.app.Fragment; import android.os.AsyncTask; import android.os.Bundle; import android.os.SystemClock; import java.lang.ref.WeakReference; import java.util.concurrent.Executors; /** * 依赖于Fragment的生命周期 */ public class CusomAsyncTaskFragment extends Fragment { // 后台任务是否继续执行 private boolean mAsynBackSmoothRunning = false; // 后台任务实例 private LoopAsynTaskUpdate mLoopAsynTaskUpdate; public void runTask(onAsynTaskUpdateListener listener, Long millisecond) { // 任务继续运行, 但是已经申请结束 if (mLoopAsynTaskUpdate != null && !mAsynBackSmoothRunning) mLoopAsynTaskUpdate = null; // 任务正在运行,不处理,直接退出 if (mLoopAsynTaskUpdate != null && mAsynBackSmoothRunning) { mLoopAsynTaskUpdate.setAsynTaskUpdateListener(listener); return; } // 开启任务 mLoopAsynTaskUpdate = new LoopAsynTaskUpdate(); mLoopAsynTaskUpdate.setAsynTaskUpdateListener(listener); mAsynBackSmoothRunning = true; mLoopAsynTaskUpdate.executeOnExecutor(Executors.newFixedThreadPool(3), millisecond); } public void updateListener(onAsynTaskUpdateListener listener) { if (mLoopAsynTaskUpdate != null) mLoopAsynTaskUpdate.setAsynTaskUpdateListener(listener); } public void stopTask() { mAsynBackSmoothRunning = false; mLoopAsynTaskUpdate = null; } public boolean getTaskStatus() { return mAsynBackSmoothRunning; } @Override public void onCreate(Bundle saveInstanceState) { super.onCreate(saveInstanceState); setRetainInstance(true); } @Override public void onDestroy() { stopTask(); super.onDestroy(); } //接口回调 public interface onAsynTaskUpdateListener { public abstract void asynTaskUpdateCallBack(Boolean update); } public class LoopAsynTaskUpdate extends AsyncTask<Long, Long, Boolean> { // 需要循环执行的次数 private WeakReference<onAsynTaskUpdateListener> mOnListener; private long mStartMillTime = 0; public void setAsynTaskUpdateListener(onAsynTaskUpdateListener listener) { mOnListener = null; mOnListener = new WeakReference<>(listener); } @Override protected Boolean doInBackground(Long... arg0) { synchronized (CusomAsyncTaskFragment.class) { long nCurrentLoopIndex = 0; while (mAsynBackSmoothRunning) { if (mStartMillTime == 0) mStartMillTime = SystemClock.elapsedRealtime(); long havePassTime = SystemClock.elapsedRealtime() - mStartMillTime; if (havePassTime < nCurrentLoopIndex * arg0[0]) { try { Thread.sleep(nCurrentLoopIndex * arg0[0] - havePassTime); } catch (InterruptedException e) { e.printStackTrace(); } } nCurrentLoopIndex++; if (mOnListener.get() == null) continue; // 通知界面当前进行的状态 publishProgress(nCurrentLoopIndex); } return true; } } @Override protected void onProgressUpdate(Long... values) { //更新进度条的回调，改成刷新界面 if (mOnListener.get() != null) mOnListener.get().asynTaskUpdateCallBack(true); } @Override protected void onPostExecute(Boolean b) { // 通知UI, 并直接返回不再循环 if (mOnListener.get() == null) return; } } }