3

動的に取得するURLからイメージビューに画像をダウンロードして表示しようとしています。この方法を試しました

 URL url = new URL(parsedWeatherResponse.getWeatherIconUrl());
            Bitmap bmp = BitmapFactory.decodeStream(url.openConnection().getInputStream());
            weather_image.setImageBitmap(bmp);

しかし、それは例外を示しています

10-04 12:22:40.221: E/AndroidRuntime(15097): FATAL EXCEPTION: main
10-04 12:22:40.221: E/AndroidRuntime(15097): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.itintestapp/com.example.itintestapp.MainActivity}: android.os.NetworkOnMainThreadException
10-04 12:22:40.221: E/AndroidRuntime(15097):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2184)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2211)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at android.app.ActivityThread.access$600(ActivityThread.java:149)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1300)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at android.os.Handler.dispatchMessage(Handler.java:99)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at android.os.Looper.loop(Looper.java:153)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at android.app.ActivityThread.main(ActivityThread.java:4987)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at java.lang.reflect.Method.invokeNative(Native Method)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at java.lang.reflect.Method.invoke(Method.java:511)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:821)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:584)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at dalvik.system.NativeStart.main(Native Method)
10-04 12:22:40.221: E/AndroidRuntime(15097): Caused by: android.os.NetworkOnMainThreadException
10-04 12:22:40.221: E/AndroidRuntime(15097):    at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1125)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at java.net.InetAddress.lookupHostByName(InetAddress.java:385)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at java.net.InetAddress.getAllByNameImpl(InetAddress.java:236)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at java.net.InetAddress.getAllByName(InetAddress.java:214)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at libcore.net.http.HttpConnection.<init>(HttpConnection.java:70)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at libcore.net.http.HttpConnection.<init>(HttpConnection.java:50)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at libcore.net.http.HttpConnection$Address.connect(HttpConnection.java:340)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at libcore.net.http.HttpConnectionPool.get(HttpConnectionPool.java:87)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at libcore.net.http.HttpConnection.connect(HttpConnection.java:128)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at libcore.net.http.HttpEngine.openSocketConnection(HttpEngine.java:316)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at libcore.net.http.HttpEngine.connect(HttpEngine.java:311)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at libcore.net.http.HttpEngine.sendSocketRequest(HttpEngine.java:290)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at libcore.net.http.HttpEngine.sendRequest(HttpEngine.java:240)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at libcore.net.http.HttpURLConnectionImpl.getResponse(HttpURLConnectionImpl.java:292)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at libcore.net.http.HttpURLConnectionImpl.getInputStream(HttpURLConnectionImpl.java:185)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at com.example.itintestapp.MainActivity.setSectorData(MainActivity.java:64)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at com.example.itintestapp.MainActivity.onCreate(MainActivity.java:40)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at android.app.Activity.performCreate(Activity.java:5020)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
10-04 12:22:40.221: E/AndroidRuntime(15097):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2148)
10-04 12:22:40.221: E/AndroidRuntime(15097):    ... 11 more

これを行う方法を教えてください.URLから画像を表示しました

私はこの方法を試しました 

class DownloadImageTask extends AsyncTask<String, Void, Bitmap> {
      ImageView bmImage;

      public DownloadImageTask(ImageView bmImage) {
          this.bmImage = bmImage;
      }

      protected Bitmap doInBackground(String... urls) {
          String urldisplay = urls[0];
          Bitmap mIcon11 = null;
          try {
            InputStream in = new java.net.URL(urldisplay).openStream();
            mIcon11 = BitmapFactory.decodeStream(in);
          } catch (Exception e) {
              Log.e("Error", e.getMessage());
              e.printStackTrace();
          }
          return mIcon11;
      }

      protected void onPostExecute(Bitmap result) {
          bmImage.setImageBitmap(result);
      }
    }

通話中

 new DownloadImageTask((ImageView) findViewById(R.id.weather_image))
            .execute(parsedWeatherResponse.getWeatherIconUrl());

この例外を取得する 

10-04 12:29:14.298: E/AndroidRuntime(15813): FATAL EXCEPTION: main
10-04 12:29:14.298: E/AndroidRuntime(15813): java.lang.NullPointerException
10-04 12:29:14.298: E/AndroidRuntime(15813):    at com.example.itintestapp.DownloadImageTask.onPostExecute(DownloadImageTask.java:32)
10-04 12:29:14.298: E/AndroidRuntime(15813):    at com.example.itintestapp.DownloadImageTask.onPostExecute(DownloadImageTask.java:1)
10-04 12:29:14.298: E/AndroidRuntime(15813):    at android.os.AsyncTask.finish(AsyncTask.java:631)
10-04 12:29:14.298: E/AndroidRuntime(15813):    at android.os.AsyncTask.access$600(AsyncTask.java:177)
10-04 12:29:14.298: E/AndroidRuntime(15813):    at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:644)
10-04 12:29:14.298: E/AndroidRuntime(15813):    at android.os.Handler.dispatchMessage(Handler.java:99)
10-04 12:29:14.298: E/AndroidRuntime(15813):    at android.os.Looper.loop(Looper.java:153)
10-04 12:29:14.298: E/AndroidRuntime(15813):    at android.app.ActivityThread.main(ActivityThread.java:4987)
10-04 12:29:14.298: E/AndroidRuntime(15813):    at java.lang.reflect.Method.invokeNative(Native Method)
10-04 12:29:14.298: E/AndroidRuntime(15813):    at java.lang.reflect.Method.invoke(Method.java:511)
10-04 12:29:14.298: E/AndroidRuntime(15813):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:821)
10-04 12:29:14.298: E/AndroidRuntime(15813):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:584)
10-04 12:29:14.298: E/AndroidRuntime(15813):    at dalvik.system.NativeStart.main(Native Method)
4

4 に答える 4

1

MainThreadつまり、ネットワーク関連の作業を実行しているため、レイアウトされていないためUIThread、画面または上にあります。これは、またはで実行する必要があるすべての時間のかかる可変操作によるものです。UIThreadViewActivityThreadPolicyAysncTaskThread

以下のようLongOperationに 、それAsyncTaskを呼び出して実行できるexecute()ものです。

new LongOperation().execute();  

private class LongOperation extends AsyncTask<String, Void, Bitmap> {

      @Override
      protected String doInBackground(Bitmap... params) 
      {
       try 
          {
          URL url = new URL(parsedWeatherResponse.getWeatherIconUrl());
          Bitmap bmp = BitmapFactory.decodeStream(url.openConnection().getInputStream());
          } 
       catch (InterruptedException e) {
          // TODO Auto-generated catch block
            e.printStackTrace();
           }
       return bmp;
      }      

      @Override
      protected void onPostExecute(Bitmap bmp) 
      {
       super.onPostExecute(result);
       weather_image.setImageBitmap(bmp);
       }

      @Override
      protected void onPreExecute() {
      }

      @Override
      protected void onProgressUpdate(Void... values) {
      }
}
于 2013-10-04T07:01:04.890 に答える
0

ダウンロードせずにWebから画像を直接表示できます。以下の機能を確認してください。Web からの画像が画像ビューに表示されます。

public static Drawable LoadImageFromWebOperations(String url) {
    try {
        InputStream is = (InputStream) new URL(url).getContent();
        Drawable d = Drawable.createFromStream(is, "src name");
        return d;
    } catch (Exception e) {
        return null;
    }
}

次に、アクティビティのコードを使用して画像を imageview に設定します。

于 2014-04-09T12:00:49.287 に答える