Я хочу показать изображение из URL я использовал растровое изображение, но изображение не отображается, но получил нулевой указатель исключение, пожалуйста, помогите меня.Я хочу показать его в виде списка текст показывает правильно, но только изображение не показываяИсключение нулевого указателя
public class CustomListViewAdapter extends ArrayAdapter<RowItem> {
Context context;
public CustomListViewAdapter(Context context, int resourceId,
List<RowItem> items) {
super(context, resourceId, items);
this.context = context;
}
/*private view holder class*/
private class ViewHolder {
ImageView imageView;
// TextView txtTitle;
TextView name;
}
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder = null;
RowItem rowItem = getItem(position);
LayoutInflater mInflater = (LayoutInflater) context
.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
if (convertView == null) {
convertView = mInflater.inflate(R.layout.list_item, null);
holder = new ViewHolder();
holder.name = (TextView) convertView.findViewById(R.id.name);
/*holder.txtTitle = (TextView) convertView.findViewById(R.id.title);*/
holder.imageView = (ImageView) convertView.findViewById(R.id.icon);
convertView.setTag(holder);
} else
holder = (ViewHolder) convertView.getTag();
holder.name.setText(rowItem.getName());
// holder.txtTitle.setText(rowItem.getTitle());
//holder.imageView.setImageResource(rowItem.getImageId());
Bitmap bitMap=downloadImage(rowItem.getImageUrl());
holder.imageView.setImageBitmap(bitMap);
// holder.imageView.setVisibility(ImageView.VISIBLE);
return convertView;
}
private Bitmap downloadImage(String url) {
Bitmap bitmap = null;
InputStream stream = null;
BitmapFactory.Options bmOptions = new BitmapFactory.Options();
bmOptions.inSampleSize = 1;
try {
stream = getHttpConnection(url);
bitmap = BitmapFactory.
decodeStream(stream, null, bmOptions);
stream.close();
} catch (IOException e1) {
e1.printStackTrace();
}
return bitmap;
}
// Makes HttpURLConnection and returns InputStream
private InputStream getHttpConnection(String urlString)
throws IOException {
InputStream stream = null;
URL url = new URL(urlString);
URLConnection connection = url.openConnection();
try {
HttpURLConnection httpConnection = (HttpURLConnection) connection;
httpConnection.setRequestMethod("GET");
httpConnection.connect();
if (httpConnection.getResponseCode() == HttpURLConnection.HTTP_OK) {
stream = httpConnection.getInputStream();
}
} catch (Exception ex) {
ex.printStackTrace();
}
return stream;
}
}
Вход кот
12-13 04:17:09.349: E/AndroidRuntime(3236): FATAL EXCEPTION: main
12-13 04:17:09.349: E/AndroidRuntime(3236): java.lang.NullPointerException
12-13 04:17:09.349: E/AndroidRuntime(3236): at com.example.gdirectory.CustomListViewAdapter.downloadImage(CustomListViewAdapter.java:80)
12-13 04:17:09.349: E/AndroidRuntime(3236): at com.example.gdirectory.CustomListViewAdapter.getView(CustomListViewAdapter.java:60)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.widget.AbsListView.obtainView(AbsListView.java:2177)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.widget.ListView.makeAndAddView(ListView.java:1840)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.widget.ListView.fillDown(ListView.java:675)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.widget.ListView.fillFromTop(ListView.java:736)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.widget.ListView.layoutChildren(ListView.java:1655)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.widget.AbsListView.onLayout(AbsListView.java:2012)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.view.View.layout(View.java:14289)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.view.ViewGroup.layout(ViewGroup.java:4562)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.widget.RelativeLayout.onLayout(RelativeLayout.java:1076)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.view.View.layout(View.java:14289)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.view.ViewGroup.layout(ViewGroup.java:4562)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.widget.FrameLayout.onLayout(FrameLayout.java:448)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.view.View.layout(View.java:14289)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.view.ViewGroup.layout(ViewGroup.java:4562)
12-13 04:17:09.349: E/AndroidRuntime(3236): at com.android.internal.widget.ActionBarOverlayLayout.onLayout(ActionBarOverlayLayout.java:349)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.view.View.layout(View.java:14289)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.view.ViewGroup.layout(ViewGroup.java:4562)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.widget.FrameLayout.onLayout(FrameLayout.java:448)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.view.View.layout(View.java:14289)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.view.ViewGroup.layout(ViewGroup.java:4562)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:1976)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1730)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1004)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:5481)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.view.Choreographer$CallbackRecord.run(Choreographer.java:749)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.view.Choreographer.doCallbacks(Choreographer.java:562)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.view.Choreographer.doFrame(Choreographer.java:532)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:735)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.os.Handler.handleCallback(Handler.java:730)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.os.Handler.dispatchMessage(Handler.java:92)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.os.Looper.loop(Looper.java:137)
12-13 04:17:09.349: E/AndroidRuntime(3236): at android.app.ActivityThread.main(ActivityThread.java:5103)
12-13 04:17:09.349: E/AndroidRuntime(3236): at java.lang.reflect.Method.invokeNative(Native Method)
12-13 04:17:09.349: E/AndroidRuntime(3236): at java.lang.reflect.Method.invoke(Method.java:525)
12-13 04:17:09.349: E/AndroidRuntime(3236): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
12-13 04:17:09.349: E/AndroidRuntime(3236): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
12-13 04:17:09.349: E/AndroidRuntime(3236): at dalvik.system.NativeStart.main(Native Method)
Будете ли вы так любезны, чтобы разместить логарифм, пожалуйста? – Kristopher
Какая строка в коде генерирует исключение нулевого указателя? –
Мое предположение: URL недействителен (код ответа не HTTP_OK), поэтому объект 'stream' имеет значение null. – Fortega