问题
What I'm trying to do is have an Android app that connects to a Google App Engine backend in order to get data from a database stored in the cloud. I've looked up some documentation and figured that Google Cloud Messaging is the best way for this. I'm stuck on trying to integrate Google App Engine with the Android app.
回答1:
GCM is great for sending small messages from GAE to the app, and particularly for waking the app and getting a message to it even if it isn't running.
Sending a request from Android to GAE via GCM is new and is not the normal way of making requests. In my personal experience with new Google stuff, I would suggest you stay far away and stick to the normal way which is to do an HTTP/REST/JSON request from an Android to a servlet on GAE.
There many Android libraries for doing this including Volley from Google (this was in use long before it was release so is not as scary as the GCM thing I was mentioning). On the server you could do it with Google Endpoints for easier authentication and cross-platform support, but it too is quite wonky (it is not fully released), so if you don't need those two features I would avoid it.
来源：https://stackoverflow.com/questions/19782186/how-do-i-make-requests-from-an-android-app-to-an-app-engine-backend