我的问题是 android.os.NetworkOnMainThreadException。我已经在堆栈溢出中查看了一些答案,但我无法解决它。
08-09 17:15:57.066: E/AndroidRuntime(6285): FATAL EXCEPTION: main
08-09 17:15:57.066: E/AndroidRuntime(6285): java.lang.RuntimeException: Unable to start activity ComponentInfo{br.com.itechtc.curtamais/br.com.itechtc.curtamais.activities.MainActivity}: android.os.NetworkOnMainThreadException
08-09 17:15:57.066: E/AndroidRuntime(6285): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2073)
08-09 17:15:57.066: E/AndroidRuntime(6285): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2098)
08-09 17:15:57.066: E/AndroidRuntime(6285): at android.app.ActivityThread.access$600(ActivityThread.java:138)
08-09 17:15:57.066: E/AndroidRuntime(6285): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1204)
08-09 17:15:57.066: E/AndroidRuntime(6285): at android.os.Handler.dispatchMessage(Handler.java:99)
08-09 17:15:57.066: E/AndroidRuntime(6285): at android.os.Looper.loop(Looper.java:137)
08-09 17:15:57.066: E/AndroidRuntime(6285): at android.app.ActivityThread.main(ActivityThread.java:4945)
08-09 17:15:57.066: E/AndroidRuntime(6285): at java.lang.reflect.Method.invokeNative(Native Method)
08-09 17:15:57.066: E/AndroidRuntime(6285): at java.lang.reflect.Method.invoke(Method.java:511)
08-09 17:15:57.066: E/AndroidRuntime(6285): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:794)
08-09 17:15:57.066: E/AndroidRuntime(6285): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:561)
08-09 17:15:57.066: E/AndroidRuntime(6285): at dalvik.system.NativeStart.main(Native Method)
08-09 17:15:57.066: E/AndroidRuntime(6285): Caused by: android.os.NetworkOnMainThreadException
08-09 17:15:57.066: E/AndroidRuntime(6285): at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1117)
08-09 17:15:57.066: E/AndroidRuntime(6285): at java.net.InetAddress.lookupHostByName(InetAddress.java:425)
08-09 17:15:57.066: E/AndroidRuntime(6285): at java.net.InetAddress.getAllByNameImpl(InetAddress.java:276)
08-09 17:15:57.066: E/AndroidRuntime(6285): at java.net.InetAddress.getAllByName(InetAddress.java:250)
08-09 17:15:57.066: E/AndroidRuntime(6285): at libcore.net.http.HttpConnection.<init>(HttpConnection.java:70)
08-09 17:15:57.066: E/AndroidRuntime(6285): at libcore.net.http.HttpConnection.<init>(HttpConnection.java:50)
08-09 17:15:57.066: E/AndroidRuntime(6285): at libcore.net.http.HttpConnection$Address.connect(HttpConnection.java:340)
08-09 17:15:57.066: E/AndroidRuntime(6285): at libcore.net.http.HttpConnectionPool.get(HttpConnectionPool.java:87)
08-09 17:15:57.066: E/AndroidRuntime(6285): at libcore.net.http.HttpConnection.connect(HttpConnection.java:128)
08-09 17:15:57.066: E/AndroidRuntime(6285): at libcore.net.http.HttpEngine.openSocketConnection(HttpEngine.java:315)
08-09 17:15:57.066: E/AndroidRuntime(6285): at libcore.net.http.HttpEngine.connect(HttpEngine.java:310)
08-09 17:15:57.066: E/AndroidRuntime(6285): at libcore.net.http.HttpEngine.sendSocketRequest(HttpEngine.java:289)
08-09 17:15:57.066: E/AndroidRuntime(6285): at libcore.net.http.HttpEngine.sendRequest(HttpEngine.java:239)
08-09 17:15:57.066: E/AndroidRuntime(6285): at libcore.net.http.HttpURLConnectionImpl.getResponse(HttpURLConnectionImpl.java:273)
08-09 17:15:57.066: E/AndroidRuntime(6285): at libcore.net.http.HttpURLConnectionImpl.getInputStream(HttpURLConnectionImpl.java:168)
08-09 17:15:57.066: E/AndroidRuntime(6285): at java.net.URL.openStream(URL.java:462)
08-09 17:15:57.066: E/AndroidRuntime(6285): at org.codehaus.jackson.JsonFactory._optimizedStreamFromURL(JsonFactory.java:935)
08-09 17:15:57.066: E/AndroidRuntime(6285): at org.codehaus.jackson.JsonFactory.createJsonParser(JsonFactory.java:530)
08-09 17:15:57.066: E/AndroidRuntime(6285): at org.codehaus.jackson.map.ObjectMapper.readValue(ObjectMapper.java:1593)
08-09 17:15:57.066: E/AndroidRuntime(6285): at br.com.itechtc.curtamais.business.PublicidadeBO.converterJson(PublicidadeBO.java:31)
08-09 17:15:57.066: E/AndroidRuntime(6285): at br.com.itechtc.curtamais.business.PublicidadeBO.<init>(PublicidadeBO.java:19)
08-09 17:15:57.066: E/AndroidRuntime(6285): at br.com.itechtc.curtamais.fragments.HomeFragment$CarregaDadosCaller.onPreExecute(HomeFragment.java:265)
08-09 17:15:57.066: E/AndroidRuntime(6285): at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:586)
08-09 17:15:57.066: E/AndroidRuntime(6285): at android.os.AsyncTask.execute(AsyncTask.java:534)
08-09 17:15:57.066: E/AndroidRuntime(6285): at br.com.itechtc.curtamais.fragments.HomeFragment.onCreateView(HomeFragment.java:57)
08-09 17:15:57.066: E/AndroidRuntime(6285): at android.support.v4.app.Fragment.performCreateView(Fragment.java:1504)
08-09 17:15:57.066: E/AndroidRuntime(6285): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:942)
08-09 17:15:57.066: E/AndroidRuntime(6285): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1121)
08-09 17:15:57.066: E/AndroidRuntime(6285): at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682)
08-09 17:15:57.066: E/AndroidRuntime(6285): at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1484)
08-09 17:15:57.066: E/AndroidRuntime(6285): at android.support.v4.app.FragmentActivity.onStart(FragmentActivity.java:571)
08-09 17:15:57.066: E/AndroidRuntime(6285): at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1166)
08-09 17:15:57.066: E/AndroidRuntime(6285): at android.app.Activity.performStart(Activity.java:5212)
08-09 17:15:57.066: E/AndroidRuntime(6285): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2046)
08-09 17:15:57.066: E/AndroidRuntime(6285): ... 11 more
首先,我使用 Jackson 将 JSON 的信息绑定到 Java 对象中。由于杰克逊,有人已经遇到过 NetworkOnMainThread 的问题吗?
我将这种方式转换为 PublicidadeBO 类:
public PublicidadeBO(String url) {
// TODO Auto-generated constructor stub
converterJson(url);
}
public void convertToJson(String url) {
lista = new ArrayList<Publicidade>();
try {
ObjectMapper mapper = new ObjectMapper();
lista = mapper.readValue(new URL(url), mapper.getTypeFactory().constructCollectionType(List.class, Publicidade.class));
} catch (IOException e) {
Log.i("json", "Erro no JSON");
e.printStackTrace();
}
}
然后在另一个 Activity 类中:
private class CarregaDadosCaller extends AsyncTask<Void, Void, Void> {
private PublicidadeBO publicidade;
private EventoBO evento;
@Override
protected void onPreExecute() {
// TODO Auto-generated method stub
publicidade = new PublicidadeBO("http://urlhere");
evento = new EventoBO("http://urlhere");
carregaDados();
super.onPreExecute();
}
@Override
protected Void doInBackground(Void... params) {
// TODO Auto-generated method stub
return null;
}
public void carregaDados() {
String publicidadeUrl = publicidade.concatenarUrlComSlug("http://urlhere");
evento.popularListaImagemChamada("http://urlhere");
evento.popularListaTitulo();
}
@Override
protected void onPostExecute(Void result) {
// TODO Auto-generated method stub
ImageViewTask taskImageView = new ImageViewTask();
taskImageView.execute(publicidadeUrl);
ImageSwitcherTask taskImageSwitcher = new ImageSwitcherTask();
String[] strArray = evento.getLinksEvento().toArray(new String[0]);
taskImageSwitcher.execute(strArray);
super.onPostExecute(result);
}
}
提前致谢。