/**   * check and delete the old package app if it exists.   */  private void checkOldPackage() {    String packageName = "xxx.xxx.xxx.xxx";    if (isAvilible(this, packageName)) {      Intent uninstall_intent = new Intent();      uninstall_intent.setAction(Intent.ACTION_DELETE);      uninstall_intent.setData(Uri.parse("package:" + packageName));      startActivity(uninstall_intent);    }  }  private boolean isAvilible(Context cxt, String packagename) {    PackageManager pm = cxt.getPackageManager();    List<PackageInfo> pinfo = pm.getInstalledPackages(0);    for (int i = 0; i < pinfo.size(); i++) {      if (pinfo.get(i).packageName.equalsIgnoreCase(packagename)) {        return true;      }    }    return false;  }