首先，你应该测试你的PHP服务分离，例如使用Chrome的邮差扩展。
当你确保PHP正常工作，下一步是Android的code连接到Web服务。

First you should test your PHP service isolated, e.g. using Chrome's PostMan extension. As you make sure PHP works properly, next step is to connect Android's code to your web service.

请检查邮递员一个不错的调试;）

Please check PostMan for a nice debugging ;)

https://chrome.google.com/webstore/detail/postman-rest-client/fdmmgilgnpjigdojojpjoooidkmcomcm?hl=en