Retrofit 1.9 回调错误

Question

我在尝试运行 Retrofit GET 调用时收到以下错误，并且该错误发生在回调中：

E/roboguice: Throwable caught during background processing
         java.lang.IllegalArgumentException: IMyClient.getUser: Must have return type or Callback as last argument, not both.
             at retrofit.RestMethodInfo.methodError(RestMethodInfo.java:107)
             at retrofit.RestMethodInfo.parseResponseType(RestMethodInfo.java:267)
             at retrofit.RestMethodInfo.<init>(RestMethodInfo.java:97)
             at retrofit.RestAdapter.getMethodInfo(RestAdapter.java:213)
             at retrofit.RestAdapter$RestHandler.invoke(RestAdapter.java:236)
             at java.lang.reflect.Proxy.invoke(Proxy.java:393)
             at $Proxy15.getUser(Unknown Source)
             at client.MyClient.getUser(MyClient.java:111)
             at task.UserProfileTask.call(UserProfileTask.java:41)
             at task.UserProfileTask.call(UserProfileTask.java:22)
             at roboguice.util.SafeAsyncTask$SafeAsyncTaskAndroidCallable.doInBackground(SafeAsyncTask.java:163)
             at roboguice.util.AndroidCallableWrapper.doDoInBackgroundThread(AndroidCallableWrapper.java:113)
             at roboguice.util.AndroidCallableWrapper.run(AndroidCallableWrapper.java:41)
             at roboguice.util.AndroidCallable.run(AndroidCallable.java:20)
             at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:423)
             at java.util.concurrent.FutureTask.run(FutureTask.java:237)
             at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
             at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
             at java.lang.Thread.run(Thread.java:818)
             at dalvik.system.VMStack.getThreadStackTrace(Native Method)
             at java.lang.Thread.getStackTrace(Thread.java:580)
             at roboguice.util.AndroidCallable.<init>(AndroidCallable.java:12)
             at roboguice.util.SafeAsyncTask$SafeAsyncTaskAndroidCallable.<init>(SafeAsyncTask.java:160)
             at roboguice.util.SafeAsyncTask.newTask(SafeAsyncTask.java:156)
             at roboguice.util.SafeAsyncTask.future(SafeAsyncTask.java:66)
             at roboguice.util.SafeAsyncTask.execute(SafeAsyncTask.java:94)
             at roboguice.util.SafeAsyncTask.execute(SafeAsyncTask.java:90)
             at ui.fragment.AccountFragment.onViewCreated(AccountFragment.java:122)
             at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1127)
             at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1290)
             at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:801)
             at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1677)
             at android.support.v4.app.FragmentController.execPendingActions(FragmentController.java:388)
             at android.support.v4.app.FragmentActivity.onStart(FragmentActivity.java:604)
             at android.support.v7.app.AppCompatActivity.onStart(AppCompatActivity.java:178)
             at roboguice.activity.RoboActionBarActivity.onStart(RoboActionBarActivity.java:106)
             at ui.activity.BaseActivity.onStart(BaseActivity.java:270)
             at ui.activity.AccountActivity.onStart(AccountActivity.java:60)
             at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1237)
             at android.app.Activity.performStart(Activity.java:6253)
             at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2379)
             at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476)
             at android.app.ActivityThread.-wrap11(ActivityThread.java)
             at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344)
             at android.os.Handler.dispatchMessage(Handler.java:102)
             at android.os.Looper.loop(Looper.java:148)
             at android.app.ActivityThread.main(ActivityThread.java:5417)
             at java.lang.reflect.Method.invoke(Native Method)
             at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
             at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)

这种模式适用于我的登录，但我是 Retrofit 的新手，似乎无法在此处找到确切的问题。

我的 IMyClient.Java 代码：

    @GET("/persons")
List<UserProfile> getUser(@Header("Authorization") String token, Callback<List<UserProfile>> callback);

在添加回调之前，这工作正常，但我当然需要能够访问响应以解析 Json。

在我的 MyClient 中，我创建了一个 IMyClient 实例，如下所示：

public List<UserProfile> getUser(String token, Callback<List<UserProfile>> callback) {
    return client.getUser(token, callback);
}

我已根据我在 Retrofit 1.9 文档中找到的回调以及它如何与我的登录名一起工作：

@Override
public List<UserProfile> call() throws Exception {
    android.os.Process.setThreadPriority(android.os.Process.THREAD_PRIORITY_BACKGROUND);
    String response = "";
    client.getUser(token, new Callback<List<UserProfile>>(){

        @Override
        public void success(List<UserProfile> profile, Response response) {
            Object data = profile;
            Object data1 = response;

        }

        @Override
        public void failure(RetrofitError error) {
            OttoBusSingleton.getInstance().post(error);
        }
    } );

    return new ArrayList<UserProfile>();
}

在这个回调中，我希望能够访问响应并从中获取 JSON。 UserProfile 是我用来设置所有 JSON 对象的模型。

我不确定为什么它可以使用登录名但不能在这里工作，非常感谢任何帮助！

Answer 1

阅读提供的堆栈跟踪：

必须将返回类型或回调作为最后一个参数，而不是两者兼有。

如果你想让请求异步就意味着这个

@GET("/persons")
void getUser(@Header("Authorization") String token, Callback<List<UserProfile>> callback);

或者如果你想让它同步

@GET("/persons")
List<UserProfile> getUser(@Header("Authorization") String token);