谷歌云消息传递API实现GCM客户端。

Question

您好，我正在按照Android官方文档发送推送通知，因为旧方法已经过时，但在实现GCM客户端时遇到了问题。

http://developer.android.com/google/gcm/client.html

教程写在这里，请往下滑动查看。

private void registerInBackground()

当我在我的应用程序中编写此函数时，它会给我返回此错误。

Syntax error on token "void", @ expected

我已经在谷歌上搜索了，现在我知道这个方法正在尝试在方法内创建一个方法的错误，但我仍然感到困惑，因为这是官方文档，我一定做错了什么，请问有人可以指出来吗？ 以下是此教程中的方法：

private void registerInBackground() {
    new AsyncTask() {
        @Override
        protected String doInBackground(Void... params) {
            String msg = "";
            try {
                if (gcm == null) {
                    gcm = GoogleCloudMessaging.getInstance(context);
                }
                regid = gcm.register(SENDER_ID);
                msg = "Device registered, registration ID=" + regid;

                // You should send the registration ID to your server over HTTP,
                // so it can use GCM/HTTP or CCS to send messages to your app.
                // The request to your server should be authenticated if your app
                // is using accounts.
                sendRegistrationIdToBackend();

                // For this demo: we don't need to send it because the device
                // will send upstream messages to a server that echo back the
                // message using the 'from' address in the message.

                // Persist the regID - no need to register again.
                storeRegistrationId(context, regid);
            } catch (IOException ex) {
                msg = "Error :" + ex.getMessage();
                // If there is an error, don't just keep trying to register.
                // Require the user to click a button again, or perform
                // exponential back-off.
            }
            return msg;
        }

        @Override
        protected void onPostExecute(String msg) {
            mDisplay.append(msg + "\n");
        }
    }.execute(null, null, null);
    ...
    /**
     * Sends the registration ID to your server over HTTP, so it can use GCM/HTTP
     * or CCS to send messages to your app. Not needed for this demo since the
     * device sends upstream messages to a server that echoes back the message
     * using the 'from' address in the message.
     */
    private void sendRegistrationIdToBackend() {
      // Your implementation here.
    }
}

现在看到sendRegistrationIdToBackend是在一个方法内部，有什么帮助吗？

- Wasif Khalil

Answer 1

我找到了一个解决方案，但很失望有33个人看到了它，但没有人回答。以下是代码：

private void registerInBackground() {
        new AsyncTask<Void, Void, String>() {
            @Override
            protected String doInBackground(Void... params) {
                String msg = "";
                try {
                    if (gcm == null) {
                        gcm = GoogleCloudMessaging.getInstance(context);
                    }
                    regid = gcm.register(SENDER_ID);
                    msg = "Device registered, registration ID=" + regid;

                    // You should send the registration ID to your server over HTTP, so it
                    // can use GCM/HTTP or CCS to send messages to your app.
                    sendRegistrationIdToBackend();

                    // For this demo: we don't need to send it because the device will send
                    // upstream messages to a server that echo back the message using the
                    // 'from' address in the message.

                    // Persist the regID - no need to register again.
                    storeRegistrationId(context, regid);
                } catch (IOException ex) {
                    msg = "Error :" + ex.getMessage();
                    // If there is an error, don't just keep trying to register.
                    // Require the user to click a button again, or perform
                    // exponential back-off.
                }
                return msg;
            }

            @Override
            protected void onPostExecute(String msg) {
                mDisplay.append(msg + "\n");
            }
        }.execute(null, null, null);
    }

- Wasif Khalil