Цепочка обработчиков Android NullPointerException
Я пытаюсь создать связь между Activity - Service - Thread от Handlers, Activity начинает Service это начинает Thread, Thread отправляет запрос на сервер, ждет ответа и отправляет его Service от Handler (работает нормально). Но когда я пытаюсь отправить сообщение от Service"s Handler в Activity приложение закрыто с NullPointerException. Что я делаю не так?
Код обработчика, основанный на изменении обработчика Android WeakReference
Моя активность
public class ActivityLogin extends Activity{
public static LoginHandler loginHandler = null;
public static class LoginHandler extends Handler {
private WeakReference<ActivityLogin> target = null;
LoginHandler(ActivityLogin target) {
this.target = new WeakReference<ActivityLogin>(target);
}
public void setTarget(ActivityLogin target) {
this.target.clear();
this.target = new WeakReference<ActivityLogin>(target);
}
@Override
public void handleMessage(Message msg) {
ActivityLogin activity = this.target.get();
if(activity == null) return;
String response = msg.getData().getString("RESPONSE");
System.err.println("RESPONSE "+response);
}
}
@Override
protected void onCreate(Bundle savedInstanceState) {
Log.d("TAG","---------------------APP STARTED---------------------");
super.onCreate(savedInstanceState);
setContentView(R.layout.layout_login);
if(loginHandler == null) loginHandler = new LoginHandler(this);
else loginHandler.setTarget(this);
}
public void onLogin(View v){
JsonUser user = new JsonUser();
user.login = "Name";
user.password = "Pazzword";
user.device = "4567-753-5768-2343";
Intent intent = new Intent(this,ComService.class);
intent.putExtra("DATA_KEY", new Gson().toJson(user));
this.startService(intent);
}
}
Мой сервис
public class ComService extends Service {
public static ServiceHandler serviceHandler = null;
public static class ServiceHandler extends Handler {
private WeakReference<ComService> target = null;
ServiceHandler(ComService target) {
this.target = new WeakReference<ComService>(target);
}
public void setTarget(ComService target) {
this.target.clear();
this.target = new WeakReference<ComService>(target);
}
@Override
public void handleMessage(Message msg) {
//ComService service = this.target.get();
//Process message (msg) and resend to activity
ActivityLogin.loginHandler.sendMessage(msg);
}
}
@Override
public void onCreate() {
super.onCreate();
if(serviceHandler == null) serviceHandler = new ServiceHandler(this);
else serviceHandler.setTarget(this);
}
@Override
public IBinder onBind(Intent intent) {
return null;
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
String message = intent.getStringExtra("DATA_KEY");
new SendData("http://xxx.xxx.xxx.xxx:27019/WebService.svc/login",message);
stopSelf(startId);
return START_REDELIVER_INTENT;
}
}
Моя тема
public class SendData extends Thread {
private String requestUrl;
private String message;
public SendData(String requestUrl, String message){
super();
this.requestUrl = requestUrl;
this.message = message;
this.start();
}
public void run(){
String serverResponse = request();
if(serverResponse == null) return;
System.err.println(serverResponse);
Message msg = new Message();
Bundle bundle = new Bundle();
bundle.putString("RESPONSE", serverResponse);
msg.setData(bundle);
ComService.serviceHandler.sendMessage(msg);
}
private String request(){...}//if need, i can post request code too
}
ОБНОВИТЬ
04-15 18:36:35.292 24524-24524/com.example.test E/Trace﹕ error opening trace file: No such file or directory (2)
04-15 18:36:35.332 24524-24524/com.example.test D/TAG﹕ ---------------------APP STARTED---------------------
04-15 18:36:35.462 24524-24524/com.example.test D/libEGL﹕ loaded /system/lib/egl/libEGL_mali.so
04-15 18:36:35.462 24524-24524/com.example.test D/libEGL﹕ loaded /system/lib/egl/libGLESv1_CM_mali.so
04-15 18:36:35.462 24524-24524/com.example.test D/libEGL﹕ loaded /system/lib/egl/libGLESv2_mali.so
04-15 18:36:35.492 24524-24524/com.example.test D/OpenGLRenderer﹕ Enabling debug mode 0
04-15 18:36:36.442 24554-24554/com.example.test:background E/Trace﹕ error opening trace file: No such file or directory (2)
04-15 18:36:36.682 24554-24567/com.example.test:background W/System.err﹕ {"status":{"success":false,"message":"some_text"},"result":null}
04-15 18:36:36.682 24554-24554/com.example.test:background D/AndroidRuntime﹕ Shutting down VM
04-15 18:36:36.682 24554-24554/com.example.test:background W/dalvikvm﹕ threadid=1: thread exiting with uncaught exception (group=0x41712300)
04-15 18:36:36.682 24554-24554/com.example.test:background E/AndroidRuntime﹕ FATAL EXCEPTION: main
java.lang.NullPointerException
at com.example.test.ComService$ServiceHandler.handleMessage(ComService.java:31)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:4745)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
at dalvik.system.NativeStart.main(Native Method)
AndroidManifext.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.test"
android:versionCode="1"
android:versionName="1.0">
<uses-sdk android:minSdkVersion="14"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.CAMERA" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.WAKE_LOCK" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-feature android:name="android.hardware.camera" android:required="true" />
<application android:label="@string/app_name" android:icon="@drawable/ic_launcher"
android:theme="@android:style/Theme.Holo.Light.NoActionBar.Fullscreen">
<activity android:name=".ActivityLogin"
android:label="@string/app_name"
android:windowSoftInputMode="stateHidden"
android:theme="@android:style/Theme.Holo.Light.NoActionBar.Fullscreen">
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
<service android:name=".ComService"
android:exported="false"
android:process=":background"
/>
</application>
</manifest>
1 ответ
В заключение я удалил Service из моего приложения. Android Service это раковая опухоль, нити без пользы. Это только мое мнение.