//在第二步的时候会有介绍

<?xml version="1.0" encoding="utf-8"?>

  
    
  

public class UpdateManager {
  private Context mContext;

  private static String savePath ;
  private String saveFileName ;
  private ProgressBar mProgress; //下载进度条控件
  private static final int DOWNLOADING = 1; //表示正在下载
  private static final int DOWNLOADED = 2; //下载完毕
  private static final int DOWNLOAD_FAILED = 3; //下载失败
  private int progress; //下载进度
  private boolean cancelFlag = false; //取消下载标志位

  private String serverVersion; //从服务器获取的版本号
  private String apkUrl;
//  private String apkUrl = "http://liuliu.lejuhuyu.com/AndroidApk/liuliu-dashou-app-1.0.2.apk";
  private String clientVersion; //客户端当前的版本号
  private String updateDescription = "请更新当前最新版本"; //更新内容描述信息
  private String forceUpdate; //是否强制更新
  private String update;
  private VersionBean mVersionBean;

  private AlertDialog alertDialog1, alertDialog2; //表示提示对话框、进度条对话框
  public UpdateManager(Context context,VersionBean versionBean) {
    this.mContext = context;
    this.mVersionBean = versionBean;
    apkUrl = "http://liuliu.lejuhuyu.com/AndroidApk/liuliu-dashou-app-"+versionBean.getLastVersion()+".apk";
    savePath = Environment.DIRECTORY_DOWNLOADS;
    saveFileName = savePath + "/liuliu-dashou-app-"+versionBean.getLastVersion()+".apk";
  }
  /** 显示更新对话框 */
  public void showNoticeDialog() {
    serverVersion = mVersionBean.getLastVersion();
    clientVersion = mVersionBean.getVersion();
    L.e("apkUrl="+apkUrl);
    L.e("savePath="+savePath);
    L.e("saveFileName="+saveFileName);
//    forceUpdate = StringUtils.getVersion();
//    forceUpdate = "1";
    forceUpdate = mVersionBean.getImportant();
    update = mVersionBean.getUpdate();
    //如果版本最新，则不需要更新
    if (serverVersion.equals(clientVersion))
      return;
    if (update.equals("2"))
      return;
    AlertDialog.Builder dialog = new AlertDialog.Builder(mContext);
    dialog.setTitle("发现新版本 ：" + serverVersion);
    dialog.setMessage(updateDescription);
    dialog.setPositiveButton("现在更新", new DialogInterface.OnClickListener() {
      @Override
      public void onClick(DialogInterface arg0, int arg1) {
        // TODO Auto-generated method stub
        arg0.dismiss();
        showDownloadDialog();
      }
    });
    //是否强制更新
    if (forceUpdate.equals("2")) {
      dialog.setNegativeButton("待会更新", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface arg0, int arg1) {
          // TODO Auto-generated method stub
          arg0.dismiss();
        }
      });
    }
    alertDialog1 = dialog.create();
    alertDialog1.setCancelable(false);
    alertDialog1.show();
  }
  /** 显示进度条对话框 */
  public void showDownloadDialog() {
    AlertDialog.Builder dialog = new AlertDialog.Builder(mContext);
    dialog.setTitle("正在更新");
    final LayoutInflater inflater = LayoutInflater.from(mContext);
    View v = inflater.inflate(R.layout.softupdate_progress, null);
    mProgress = (ProgressBar) v.findViewById(R.id.update_progress);
    dialog.setView(v);
    //如果是强制更新，则不显示取消按钮
//    if (forceUpdate.equals("1")) {
//      dialog.setNegativeButton("取消", new DialogInterface.OnClickListener() {
//        @Override
//        public void onClick(DialogInterface arg0, int arg1) {
//          // TODO Auto-generated method stub
//          arg0.dismiss();
//          cancelFlag = false;
//        }
//      });
//    }
    alertDialog2 = dialog.create();
    alertDialog2.setCancelable(false);
    alertDialog2.show();

    //下载apk
    downloadAPK();
  }
  DownloadManager manager;
  Cursor cursor;
  DownloadManager.Request down;
  DownloadManager.Query query;
  ContentObserver contentObserver;
  /** 下载apk的线程 */
  public void downloadAPK() {
    manager = (DownloadManager) LiuLiuApplication.getContext().getSystemService(Context.DOWNLOAD_SERVICE);
    down = new DownloadManager.Request(Uri.parse(apkUrl));
    // 设置允许使用的网络类型，这里是移动网络和wifi都可以
    down.setAllowedNetworkTypes(DownloadManager.Request.NETWORK_MOBILE
        | DownloadManager.Request.NETWORK_WIFI);
    // 显示下载界面
    down.setVisibleInDownloadsUi(true);
    // 设置下载路径和文件名
    down.setDestinationInExternalPublicDir(Environment.DIRECTORY_DOWNLOADS, "liuliu-dashou-app-"+mVersionBean.getLastVersion() + ".apk");
    down.setMimeType("application/vnd.android.package-archive");
    // 设置为可被媒体扫描器找到
    down.allowScanningByMediaScanner();
    down.setAllowedOverRoaming(false);
//    down.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED);
    long id = manager.enqueue(down);
    query = new DownloadManager.Query().setFilterById(id);
    contentObserver = new ContentObserver(mHandler) {
      @Override
      public void onChange(boolean selfChange) {
//        super.onChange(selfChange);
        boolean downloading = true;
        while(downloading){
          cursor = manager.query(query);
          try {
            if (cursor != null && cursor.moveToFirst()) {
              int bytes_downloaded = cursor.getInt(cursor.getColumnIndex(DownloadManager.COLUMN_BYTES_DOWNLOADED_SO_FAR));
              int bytes_total = cursor.getInt(cursor.getColumnIndex(DownloadManager.COLUMN_TOTAL_SIZE_BYTES));
              progress = (int) ((bytes_downloaded * 100) / bytes_total);
              mHandler.sendEmptyMessage(DOWNLOADING);
              if (cursor.getInt(cursor.getColumnIndex(DownloadManager.COLUMN_STATUS))==DownloadManager.STATUS_SUCCESSFUL) {
                mHandler.sendEmptyMessage(DOWNLOADED);
              }else if (cursor.getInt(cursor.getColumnIndex(DownloadManager.COLUMN_STATUS))==DownloadManager.STATUS_FAILED){
                mHandler.sendEmptyMessage(DOWNLOAD_FAILED);
              }
            }
          }catch (Exception e){
            e.printStackTrace();
            mHandler.sendEmptyMessage(DOWNLOAD_FAILED);
          }finally {
            if (cursor != null){
              downloading = false;
              cursor.close();
            }
          }
        }
      }
    };
    mContext.getContentResolver().registerContentObserver(Uri.parse("content://downloads/"),true,contentObserver);
  }

  /** 更新UI的handler */
  private Handler mHandler = new Handler() {
    @Override
    public void handleMessage(Message msg) {
      // TODO Auto-generated method stub
      switch (msg.what) {
        case DOWNLOADING:
          mProgress.setProgress(progress);
          break;
        case DOWNLOADED:
          if (alertDialog2 != null)
            alertDialog2.dismiss();
          installAPK();
          break;
        case DOWNLOAD_FAILED:
          ToastUtil.getInstance(mContext,"网络断开，请稍候再试",false).show();
          break;
        default:
          break;
      }
    }
  };

  /** 下载完成后自动安装apk */
  public void installAPK() {
    File apkFile = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS),"liuliu-dashou-app-"+mVersionBean.getLastVersion() + ".apk");

    if (!apkFile.exists()) {
      return;
    }
    if (Build.VERSION.SDK_INT>=24){
     
      Uri apkUri = FileProvider.getUriForFile(mContext, LiuLiuApplication.getContext().getPackageName()+".fileprovider", apkFile);
      Intent install = new Intent(Intent.ACTION_VIEW);
      install.addCategory(Intent.CATEGORY_DEFAULT);
      install.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
      install.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
      install.setDataAndType(apkUri, "application/vnd.android.package-archive");
      mContext.startActivity(install);
    } else {
      Intent intent = new Intent();
      intent.setAction(Intent.ACTION_VIEW);
      intent.addCategory(Intent.CATEGORY_DEFAULT);
      intent.setType("application/vnd.android.package-archive");
      intent.setData(Uri.fromFile(apkFile));
      intent.setDataAndType(Uri.fromFile(apkFile), "application/vnd.android.package-archive");
      intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
      mContext.startActivity(intent);
    }

  }
}