我该怎么做这个例外？
我将目标sdkVersion更改为13.出现此问题！ 出了什么问题？
这是我尝试加载广告后的logcat输出
02-04 12:51:23.910: E/AndroidRuntime(7379): FATAL EXCEPTION: main
02-04 12:51:23.910: E/AndroidRuntime(7379): android.os.NetworkOnMainThreadException
02-04 12:51:23.910: E/AndroidRuntime(7379): at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1099)
02-04 12:51:23.910: E/AndroidRuntime(7379): at java.net.InetAddress.lookupHostByName(InetAddress.java:391)
02-04 12:51:23.910: E/AndroidRuntime(7379): at java.net.InetAddress.getAllByNameImpl(InetAddress.java:242)
02-04 12:51:23.910: E/AndroidRuntime(7379): at java.net.InetAddress.getAllByName(InetAddress.java:220)
02-04 12:51:23.910: E/AndroidRuntime(7379): at libcore.net.http.HttpConnection.<init>(HttpConnection.java:71)
02-04 12:51:23.910: E/AndroidRuntime(7379): at libcore.net.http.HttpConnection.<init>(HttpConnection.java:50)
02-04 12:51:23.910: E/AndroidRuntime(7379): at libcore.net.http.HttpConnection$Address.connect(HttpConnection.java:351)
02-04 12:51:23.910: E/AndroidRuntime(7379): at libcore.net.http.HttpConnectionPool.get(HttpConnectionPool.java:86)
02-04 12:51:23.910: E/AndroidRuntime(7379): at libcore.net.http.HttpConnection.connect(HttpConnection.java:128)
02-04 12:51:23.910: E/AndroidRuntime(7379): at libcore.net.http.HttpEngine.openSocketConnection(HttpEngine.java:308)
02-04 12:51:23.910: E/AndroidRuntime(7379): at libcore.net.http.HttpsURLConnectionImpl$HttpsEngine.makeSslConnection(HttpsURLConnectionImpl.java:460)
02-04 12:51:23.910: E/AndroidRuntime(7379): at libcore.net.http.HttpsURLConnectionImpl$HttpsEngine.connect(HttpsURLConnectionImpl.java:432)
02-04 12:51:23.910: E/AndroidRuntime(7379): at libcore.net.http.HttpEngine.sendSocketRequest(HttpEngine.java:282)
02-04 12:51:23.910: E/AndroidRuntime(7379): at libcore.net.http.HttpEngine.sendRequest(HttpEngine.java:232)
02-04 12:51:23.910: E/AndroidRuntime(7379): at libcore.net.http.HttpURLConnectionImpl.connect(HttpURLConnectionImpl.java:80)
02-04 12:51:23.910: E/AndroidRuntime(7379): at libcore.net.http.HttpsURLConnectionImpl.connect(HttpsURLConnectionImpl.java:164)
02-04 12:51:23.910: E/AndroidRuntime(7379): at com.sfa.coverflow.ImageLoader.DisplayAdvert(ImageLoader.java:93)
02-04 12:51:23.910: E/AndroidRuntime(7379): at com.sfa.coverflow.MainActivity$LoadAdvert.onPostExecute(MainActivity.java:869)
02-04 12:51:23.910: E/AndroidRuntime(7379): at com.sfa.coverflow.MainActivity$LoadAdvert.onPostExecute(MainActivity.java:1)
02-04 12:51:23.910: E/AndroidRuntime(7379): at android.os.AsyncTask.finish(AsyncTask.java:602)
02-04 12:51:23.910: E/AndroidRuntime(7379): at android.os.AsyncTask.access$600(AsyncTask.java:156)
02-04 12:51:23.910: E/AndroidRuntime(7379): at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:615)
02-04 12:51:23.910: E/AndroidRuntime(7379): at android.os.Handler.dispatchMessage(Handler.java:99)
02-04 12:51:23.910: E/AndroidRuntime(7379): at android.os.Looper.loop(Looper.java:137)
02-04 12:51:23.910: E/AndroidRuntime(7379): at android.app.ActivityThread.main(ActivityThread.java:4446)
02-04 12:51:23.910: E/AndroidRuntime(7379): at java.lang.reflect.Method.invokeNative(Native Method)
02-04 12:51:23.910: E/AndroidRuntime(7379): at java.lang.reflect.Method.invoke(Method.java:511)
02-04 12:51:23.910: E/AndroidRuntime(7379): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
02-04 12:51:23.910: E/AndroidRuntime(7379): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
02-04 12:51:23.910: E/AndroidRuntime(7379): at dalvik.system.NativeStart.main(Native Method)
这是我的DisplayAdvert方法：
int advert_id = R.drawable.loader;
public void DisplayAdvert(String image_url, int loader, ImageView image) {
// TODO Auto-generated method stub
advert_id = loader;
imageViews.put(image, image_url);
try {
URL url = new URL(image_url);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setDoInput(true);
connection.connect();
InputStream input = connection.getInputStream();
Bitmap myBitmap = BitmapFactory.decodeStream(input);
if(myBitmap!=null)
image.setImageBitmap(myBitmap);
else
{
queuePhoto(image_url, image);
image.setImageResource(loader);
}
} catch (IOException e) {
e.printStackTrace();
}
}
这是我的LoadAdvert方法：
/**
* Background Async Task to Load all product by making HTTP Request
* */
class LoadAdvert extends AsyncTask<String, String, String> {
/**
* getting All products from url
* */
protected String doInBackground(String... args) {
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
// getting JSON string from URL
JSONObject json = jParser.makeHttpRequest(url_advertisement, "GET", params);
// Check your log cat for JSON reponse
Log.d("Advert: ", json.toString());
try {
// Checking for SUCCESS TAG
int success = json.getInt(TAG_SUCCESS);
if (success == 1) {
// ADVERT FOUND
// RETRIEVE ADVENT URL
advert = json.getJSONArray(TAG_PHOTOS);
for (int i = 0; i < advert.length(); i++) {
JSONObject c = advert.getJSONObject(i);
// STORE EACH JSON ITEM IN VARIABLE
banner_url = c.getString(TAG_BANNER_IMAGE);
banner_url = banner_url.toString();
Log.d("banner URL", banner_url);
advert_url = c.getString(TAG_ADVERT_URL);
advert_url = advert_url.toString();
Log.d("advert URL", advert_url);
}
}
else {
}
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
/**
* After completing background task Dismiss the progress dialog
* **/
protected void onPostExecute(String file_url) {
// Loader image - will be shown before loading image
int loader = R.drawable.loader;
// Imageview to show
ImageView image = (ImageView) findViewById(R.id.img_advert);
// Image url
String imageUrl = banner_url;
// ImageLoader class instance
ImageLoader imgLoader = new ImageLoader(getApplicationContext());
// whenever you want to load an image from url
// call DisplayImage function
// url - image url to load
// loader - loader image, will be displayed before getting image
// image - ImageView
imgLoader.DisplayAdvert(imageUrl, loader, image);
}
}
}
答案 0 :(得分：2)
堆栈跟踪的这一部分是“杀手”;
at libcore.net.http.HttpsURLConnectionImpl.connect(HttpsURLConnectionImpl.java:164)
at com.sfa.coverflow.ImageLoader.DisplayAdvert(ImageLoader.java:93)
at com.sfa.coverflow.MainActivity$LoadAdvert.onPostExecute(MainActivity.java:869)
当AsyncTask完成时，在GUI线程上执行的onPostExecute调用DisplayAdvert，并立即调用HttpsURLConnectionImpl.connect。由于新API版本中的GUI线程不允许网络访问，因此会抛出异常。
DisplayAdvert内的网络访问需要在非GUI线程中完成，因为它执行网络I / O.
最简单的方法是在DisplayAdvert方法中创建新的AsyncTask，在doInBackground()中进行网络访问，并使用onPostExecute()中的提取数据更新GUI。
答案 1 :(得分：0)
如果您只是想测试代码，那么您可以将以下代码添加到onCreate()
if (android.os.Build.VERSION.SDK_INT > 9) {
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build(); StrictMode.setThreadPolicy(policy);
}
您不希望这是永久性的，因为UI线程上的网络操作在使用应用程序时会带来糟糕的体验，但在测试时非常有用。
答案 2 :(得分：0)
将您的DisplayAdvert方法放在doInBackground中，因为您无法在api级别11及以上的主线程上执行网络操作
请参阅此Resource
答案 3 :(得分：0)
您不应该在主线程中执行网络操作。
在您发布的代码中，您正在display()中执行网络操作，并在onPost()的{{1}}中进行调用。
在AsycTask中，只有AsyncTask在另一个线程中执行，方法doInBackground()在主线程本身中执行。
请随时再提出疑问。
答案 4 :(得分：0)
针对Honeycomb的应用程序将获得此异常，不应在主UI线程中允许网络操作。
您必须在单独的线程（多线程）中执行所有网络操作或使用AsyncTask。
<强>更新
public void DisplayAdvert(final String image_url, final int loader, final ImageView image)
{
advert_id = loader;
imageViews.put(image, image_url);
try
{
new Thread(new Runnable()
{
Bitmap myBitmap;
public void run()
{
try
{
URL url = new URL(image_url);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setDoInput(true);
connection.connect();
InputStream input = connection.getInputStream();
myBitmap = BitmapFactory.decodeStream(input);
}
catch(Exception e)
{
e.printStackTrace();
}
runOnUiThread(new Runnable()
{
public void run()
{
if(myBitmap!=null)
image.setImageBitmap(myBitmap);
else
{
queuePhoto(image_url, image);
image.setImageResource(loader);
}
}
});
}
}).start();
}
catch (Exception e)
{
e.printStackTrace();
}
}