我的目标是创建一个列表，当我更改表格中的一行时立即刷新我在Asynctask中使用相同的代码并且它完美地运行，问题似乎来自服务。
以下是我如何调用我的服务方法
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_liste_offre);
new ConsultationOffreAsyncTask().execute();
Intent intent = new Intent(this, ServiceConsultation.class);
bindService(intent, myConnection, Context.BIND_AUTO_CREATE);
try{
}catch(NullPointerException e){
e.printStackTrace();
}
listview = (ListView) this.findViewById(R.id.listeoffre);
这是相应的方法GetOffres（）
public void GetOffres() {
Runnable runnable = new Runnable() {
public void run() {
try {
String myurl = "http://10.0.2.2/PixelsTrade/consultation_offre.php";
List<NameValuePair> params = new ArrayList<NameValuePair>();
JSONParser json = new JSONParser();
JSONObject result = json.makeHttpRequest(myurl, "POST",
params);
offre.open();
JSONArray productObjectArray = result
.getJSONArray("offre");
for (int j = 0; j < productObjectArray.length(); j++) {
JSONObject productObject = productObjectArray
.getJSONObject(j);
int b = 0;
if (b != productObject.getInt("CodeOffre")) {
b = productObject.getInt("CodeOffre");
if (offre.chekOffre(b) == false) {
offre.insertOffre(productObject
.getInt("CodeOffre"), productObject
.getString("NomOffre"),
productObject.getInt("CodeUser"),
productObject
.getString("DateDebut"),
productObject.getString("DateFin"),
productObject
.getString("Description"),
productObject.getString("maj"));
Log.i("insert", "insert rows");
} else if (offre.chekOffre(b) == true) {
offre.updateOffre(productObject
.getInt("CodeOffre"), productObject
.getString("NomOffre"),
productObject.getInt("CodeUser"),
productObject
.getString("DateDebut"),
productObject.getString("DateFin"),
productObject
.getString("Description"),
productObject.getString("maj"));
Log.i("update", "update rows");
}
}
}
offre.close();
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
};
Thread mythread = new Thread(runnable);
mythread.start();
offre = new OffreBDD(ListeOffre.this);
offre.open();// c est pour autoriser l acces de lire de la base
// get all produits
list = (ArrayList<Offre>) offre.getAllOffres();
myAdapter = new AdapterOffre(ListeOffre.this, list);
listview.setAdapter(myAdapter);
offre.close();
}
我在调用myService.getOffre（）的行中得到NullPointerException 有人可以告诉错误在哪里
这是您提出的logcat
04-12 17:22:25.972: W/System.err(7990): java.lang.NullPointerException
04-12 17:22:25.982: W/System.err(7990): at com.Consultation.applicationpfe.ListeOffre.onCreate(ListeOffre.java:59)
04-12 17:22:25.982: W/System.err(7990): at android.app.Activity.performCreate(Activity.java:5104)
04-12 17:22:25.982: W/System.err(7990): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
04-12 17:22:25.982: W/System.err(7990): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
04-12 17:22:25.982: W/System.err(7990): at android.app.ActivityThread.startActivityNow(ActivityThread.java:2023)
04-12 17:22:25.982: W/System.err(7990): at android.app.LocalActivityManager.moveToState(LocalActivityManager.java:135)
04-12 17:22:25.982: W/System.err(7990): at android.app.LocalActivityManager.startActivity(LocalActivityManager.java:347)
04-12 17:22:25.982: W/System.err(7990): at android.widget.TabHost$IntentContentStrategy.getContentView(TabHost.java:749)
04-12 17:22:25.992: W/System.err(7990): at android.widget.TabHost.setCurrentTab(TabHost.java:413)
04-12 17:22:25.992: W/System.err(7990): at android.widget.TabHost$2.onTabSelectionChanged(TabHost.java:154)
04-12 17:22:25.992: W/System.err(7990): at android.widget.TabWidget$TabClickListener.onClick(TabWidget.java:546)
04-12 17:22:25.992: W/System.err(7990): at android.view.View.performClick(View.java:4204)
04-12 17:22:25.992: W/System.err(7990): at android.view.View$PerformClick.run(View.java:17355)
04-12 17:22:26.002: W/System.err(7990): at android.os.Handler.handleCallback(Handler.java:725)
04-12 17:22:26.002: W/System.err(7990): at android.os.Handler.dispatchMessage(Handler.java:92)
04-12 17:22:26.002: W/System.err(7990): at android.os.Looper.loop(Looper.java:137)
04-12 17:22:26.002: W/System.err(7990): at android.app.ActivityThread.main(ActivityThread.java:5041)
04-12 17:22:26.002: W/System.err(7990): at java.lang.reflect.Method.invokeNative(Native Method)
04-12 17:22:26.012: W/System.err(7990): at java.lang.reflect.Method.invoke(Method.java:511)
04-12 17:22:26.012: W/System.err(7990): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
04-12 17:22:26.021: W/System.err(7990): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
04-12 17:22:26.021: W/System.err(7990): at dalvik.system.NativeStart.main(Native Method)
以下是我对该服务进行绑定的方式。
eprivate ServiceConnection myConnection = new ServiceConnection() {
public void onServiceConnected(ComponentName className, IBinder service) {
MyBinder binder = (MyBinder) service;
myService = binder.getService();
isBound = true;
myService.GetOffres();
Log.i("service", "service connected");
}
public void onServiceDisconnected(ComponentName arg0) {
isBound = false;
}
void doBindService() {
// Establish a connection with the service. We use an explicit
// class name because we want a specific service implementation that
// we know will be running in our own process (and thus won't be
// supporting component replacement by other applications).
bindService(new Intent(ListeOffre.this,
ServiceConsultation.class), myConnection, Context.BIND_AUTO_CREATE);
isBound = true;
}
void doUnbindService() {
if (isBound) {
// Detach our existing connection.
unbindService(myConnection);
isBound = false;
}
}
答案 0 :(得分：0)
您没有显示处理服务绑定回调的方式/位置。你应该有这样的东西（主要来自Bound Services page：
/** Defines callbacks for service binding, passed to bindService() */
private ServiceConnection myConnection = new ServiceConnection() {
@Override
public void onServiceConnected(ComponentName className,
IBinder service) {
// We've bound to LocalService, cast the IBinder and get LocalService instance
LocalBinder binder = (LocalBinder) service;
mService = binder.getService();
mBound = true;
}
@Override
public void onServiceDisconnected(ComponentName arg0) {
mBound = false;
}
};
}
答案 1 :(得分：0)
我找到了问题的解决方案，似乎我在清单中使用错误的名称声明了服务。 谢谢你的提议。