GCM更新7.5到8.3.0致命异常

Question

我尝试在Gradle项目中更新GCM服务(Google云消息)库(从7.5到8.3.0).但是现在,有了这个新版本,我无法启动之前完美运行的先前活动.

处理以下错误的代码是:

Intent in = new Intent(this, MyGcmListenerService.class);
startService(in);

MyGcmListenerService.java:

public class MyGcmListenerService extends GcmListenerService
{
    private static final String TAG = "MyGcmListenerService";

    @Override
    public void onMessageReceived(String from, Bundle data)
    {
        Log.w(TAG, "onMessageReceived");
    }

返回的错误:

FATAL EXCEPTION: AsyncTask #1
java.lang.NullPointerException: Attempt to invoke virtual method 'int java.lang.String.hashCode()' on a null object reference
E/AndroidRuntime:     at com.google.android.gms.gcm.GcmListenerService.zzo(Unknown Source)
E/AndroidRuntime:     at com.google.android.gms.gcm.GcmListenerService.zza(Unknown Source)
E/AndroidRuntime:     at com.google.android.gms.gcm.GcmListenerService$1.run(Unknown Source)
E/AndroidRuntime:     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
E/AndroidRuntime:     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
E/AndroidRuntime:     at java.lang.Thread.run(Thread.java:818)

Gradle文件:

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    compile 'com.android.support:appcompat-v7:21.0.3'
    compile 'com.google.android.gms:play-services-gcm:8.3.0'
}

如果我回滚到之前的GCM版本(7.5),它会按预期工作.你知道改变了什么吗？我检查了更改日志,但我无法找到有关它的任何信息. https://developers.google.com/android/guides/releases

谢谢您的帮助

Answer 1

尝试查看反编译的类文件以GcmListenerService使用IDE.当我使用Android Studio for 8.3.0版本时,看起来抛出异常的代码试图从调用服务的意图中获取ACTION.因为您使用显式意图调用服务,所以ACTION为null.

我想知道你为什么要GcmListenerService显式调用你的子类？消息接收的正常GCM处理是将消息传递给消息GcmReceiver,然后将消息传递给应用程序的实例以GcmListenerService进行处理.您不应该显式调用您的侦听器服务,GcmReceiver这样做.看一下示例项目.