android Toast提示异常：java.lang.RuntimeException: Can't create handler inside thread that has not called

Toast只能在UI线程弹出，解决此问题可以在Toast前后加两行代码，如下所示：

 　　　　　　Looper.prepare();
           Toast.makeText(getApplicationContext(),"操作失败："+r.Message,Toast.LENGTH_LONG).show();
           Looper.loop();