Android中的AlertDialog遇到的错误

public void showAddIPCDialog() {
    Log.i("ssssssssss","wwwwwwwwww");
    LayoutInflater inflater = this.getActivity().getLayoutInflater();
    Log.i("ssssssssssinflater",inflater+"");
//错误
  //  final View layout = inflater.inflate(R.layout.addipc, (ViewGroup) findViewById(R.id.addipc_dialog));//添加布局

//正确
   final View layout = inflater.inflate(R.layout.addipc, null);//添加布局

    Log.i("sssssssssslayout",layout+"");
  EditText etName = (EditText) layout.findViewById(R.id.et_camera_name);
    EditText edit = (EditText) layout.findViewById(R.id.sn);
    EditText editps = (EditText) layout.findViewById(R.id.password);

    new AlertDialog.Builder(this.getActivity()).setTitle("添加监控摄像头").setView(layout)
            .setPositiveButton("确定", new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface arg0, int arg1) {
                  
                }
            }).setNegativeButton("取消", null).show();
}

//总结：复制需谨慎