(Android Studio) Connecting an app to Google Endpoints Module - google-app-engine

Question

I'm having trouble following the second step here.
I really don't understand how this sample does anything other than return a simple toast message. How does it utilize the API to display that message?
class EndpointsAsyncTask extends AsyncTask<Pair<Context, String>, Void, String> {
private static MyApi myApiService = null;
private Context context;
#Override
protected String doInBackground(Pair<Context, String>... params) {
if(myApiService == null) { // Only do this once
MyApi.Builder builder = new MyApi.Builder(AndroidHttp.newCompatibleTransport(),
new AndroidJsonFactory(), null)
// options for running against local devappserver
// - 10.0.2.2 is localhost's IP address in Android emulator
// - turn off compression when running against local devappserver
.setRootUrl("http://10.0.2.2:8080/_ah/api/")
.setGoogleClientRequestInitializer(new GoogleClientRequestInitializer() {
#Override
public void initialize(AbstractGoogleClientRequest<?> abstractGoogleClientRequest) throws IOException {
abstractGoogleClientRequest.setDisableGZipContent(true);
}
});
// end options for devappserver
myApiService = builder.build();
}
context = params[0].first;
String name = params[0].second;
try {
return myApiService.sayHi(name).execute().getData();
} catch (IOException e) {
return e.getMessage();
}
}
#Override
protected void onPostExecute(String result) {
Toast.makeText(context, result, Toast.LENGTH_LONG).show();
}
I'm afraid my this sample is too complex for my limited knowledge. How exactly do I "talk" to the Google Endpoints Module when running an app? Specifically, What is EndpointsAsyncTask();?
Are there any resources listing all the methods available to me? Is there a simpler example of an app communicating with a Google Cloud Endpoint?

Answer 1

The service methods available to you are defined by the backend source in section 1.
In the example you posted, this line: myApiService.sayHi(name).execute()
is an actual invocation call to the backend that you defined by annotating #ApiMethod("sayHi") on the method in the MyEndpoint.java class of your backend module.
The reason your Android app defines an EndpointsAsyncTask is because slow operations such as calls that hit the network need to happen off of the UI thread to avoid locking the UI. The demo simply puts the returned value into a Toast but you could modify onPostExecute() to do whatever you'd like with the result.
For more info on Google Endpoints check out:
https://cloud.google.com/appengine/docs/java/endpoints/
And for info about using an Android AsyncTask look here:
http://developer.android.com/reference/android/os/AsyncTask.html