Android下载APK并自动安装

1、利用xUtils第三方jar包下载APK文件

HttpUtils httpUtils = new HttpUtils();

httpUtils.download(String url, String target, RequestCallBack callback) {...};

2、自动安装，发送Intent给系统的PackageInstaller

  Intent intent = new Intent();
        intent.setAction(Intent.ACTION_VIEW);
//  intent.addCategory(Intent.CATEGORY_DEFAULT);
        intent.setDataAndType(Uri.fromFile(new File(target)),"application/vnd.android.package-archive");
        startActivity(intent);