Получить растрового изображения из Url

Question

Я хочу, чтобы получить Bitmap изображение из Url:

Bitmap mage = getBitmapFromUrl(urlPhotoInFrameFirst); 

public static Bitmap getBitmapFromUrl (String uri){ 
    URL url = null; 
    try { 
     url = new URL(uri); 
     Bitmap image = BitmapFactory.decodeStream(url.openConnection().getInputStream()); 
     return image; 
    } catch (MalformedURLException e) { 
     e.printStackTrace(); 
    } catch (IOException e) { 
     e.printStackTrace(); 
    } 
    return null; 
} 

Но приложение остановка в этой строке:

Bitmap image = BitmapFactory.decodeStream(url.openConnection().getInputStream()); 

Ошибка:

FATAL EXCEPTION: main android.os.NetworkOnMainThreadException at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1117) at java.net.InetAddress.lookupHostByName(InetAddress.java:385) at java.net.InetAddress.getAllByNameImpl(InetAddress.java:236) at java.net.InetAddress.getAllByName(InetAddress.java:214) at libcore.net.http.HttpConnection.(HttpConnection.java:70) at libcore.net.http.HttpConnection.(HttpConnection.java:50) at libcore.net.http.HttpConnection$Address.connect(HttpConnection.java:341) at libcore.net.http.HttpConnectionPool.get(HttpConnectionPool.java:87) at libcore.net.http.HttpConnection.connect(HttpConnection.java:128) at libcore.net.http.HttpEngine.openSocketConnection(HttpEngine.java:315) at libcore.net.http.HttpsURLConnectionImpl$HttpsEngine.makeSslConnection(HttpsURLConnectionImpl.java:461) at libcore.net.http.HttpsURLConnectionImpl$HttpsEngine.connect(HttpsURLConnectionImpl.java:433) at libcore.net.http.HttpEngine.sendSocketRequest(HttpEngine.java:289) at libcore.net.http.HttpEngine.sendRequest(HttpEngine.java:239) at libcore.net.http.HttpURLConnectionImpl.getResponse(HttpURLConnectionImpl.java:273) at libcore.net.http.HttpURLConnectionImpl.getInputStream(HttpURLConnectionImpl.java:168) at libcore.net.http.HttpsURLConnectionImpl.getInputStream(HttpsURLConnectionImpl.java:271) at com.example.sivolotskiy.multiexpro.util.BitmapLoader.getBitmapFromUrl(BitmapLoader.java:33) at com.example.sivolotskiy.multiexpro.ui.EditFragment.setImageInFrames(EditFragment.java:161) at com.example.sivolotskiy.multiexpro.ui.EditFragment.startAfterView(EditFragment.java:119) at com.example.sivolotskiy.multiexpro.ui.EditFragment_.onViewChanged(EditFragment_.java:202) at org.androidannotations.api.view.OnViewChangedNotifier.notifyViewChanged(OnViewChangedNotifier.java:41) at com.example.sivolotskiy.multiexpro.ui.EditFragment_.onViewCreated(EditFragment_.java:71) at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:843) at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1035) at android.app.BackStackRecord.run(BackStackRecord.java:635) at android.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1397) at android.app.FragmentManagerImpl$1.run(FragmentManager.java:426) at android.os.Handler.handleCallback(Handler.java:615) at android.os.Handler.dispatchMessage(Handler.java:92) at android.os.Looper.loop(Looper.java:137) at android.app.ActivityThread.main(ActivityThread.java:4745) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:511) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553) at dalvik.system.NativeStart.main(Native Method)

Answer 1

Как говорит исключение вы не можете выполнять сетевые вызовы в потоке Main (UI). Поэтому вам нужно обернуть свой код в runnable/thread и вызвать его. Может выглядеть следующим образом:

public static class GetBitmapTask implements Runnable { 

    private final String uri; 
    private final Callback callback; 

    public GetBitmapTask(String uri, Callback callback) { 
     this.uri = uri; 
     this.callback = callback; 
    } 

    @Override public void run() { 
     try { 
      URL url = new URL(uri); 
      Bitmap bmp = BitmapFactory.decodeStream(url.openConnection().getInputStream()); 
      callback.onFinish(bmp); 
     } catch (IOException e) { 
      callback.onError(e); 
     } 
    } 

    public interface Callback{ 
     void onFinish(Bitmap bitmap); 
     void onError(Throwable t); 
    } 
} 

Использование:

new Thread(new GetBitmapTask("", new GetBitmapTask.Callback() { 
    @Override public void onFinish(Bitmap bitmap) { 
     //here is your bitmap 
    } 

    @Override public void onError(Throwable t) { 
     //here you have to handle error 
    } 
})).start(); 

Или даже лучше метод: use a library for loading images.