使用Universal Image Loader加载我的listview时遇到问题。问题是我不知道函数调用它的位置因为总是出现RuntimeException。异常是由于doinBackground中的ImageLoader。
我的代码如下：
公共类Listview extends Activity实现了View.OnClickListener {
private ListView lstView;
private ImageAdapter imageAdapter;
ArrayList<HashMap<String, Object>> MyArrList = new ArrayList<HashMap<String, Object>>();
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// ProgressBar
requestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS);
setContentView(R.layout.activity_list);
// ListView and imageAdapter
lstView = (ListView) findViewById(R.id.listView1);
lstView.setClipToPadding(false);
imageAdapter = new ImageAdapter(getApplicationContext());
imageAdapter.notifyDataSetChanged();//When add new photos, refresh the view
lstView.setAdapter(imageAdapter);
lstView.invalidateViews();
setProgressBarIndeterminateVisibility(true);
new LoadContentFromServer().execute();
}
class LoadContentFromServer extends AsyncTask<Object, Integer, Object> {
@Override
protected Object doInBackground(Object... params) {
String url = "http://xxxxxxxxxxxxxx/xxxxxxx/Xxxx.php";
String photo_id_new;
String photo_id_prev = "";
JSONArray data;
imageAdapter.notifyDataSetChanged();
try {
data = new JSONArray(getJSONUrl(url));
MyArrList = new ArrayList<HashMap<String, Object>>();
HashMap<String, Object> map;
for(int i = 0; i < data.length(); i++) {
JSONObject c = data.getJSONObject(i);
map = new HashMap<String, Object>();
photo_id_new = c.getString("photo_id");
map.put("ImageID", c.getString("photo_id"));
map.put("NameAcc", c.getString("nameacc"));
map.put("PriceAcc", c.getString("price"));
map.put("BrandAcc", c.getString("brand"));
map.put("Shopname", c.getString("shopname"));
map.put("Shopcity", c.getString("city"));
map.put("Shopcountry", c.getString("country"));
map.put("UserName", c.getString("forename"));
map.put("UserSurname", c.getString("surname"));
//If the new photo it's different to the previous, doesn't show and create more rows
if(!photo_id_prev.equals(photo_id_new)){
// Thumbnail Get ImageBitmap To Object
//Bitmap newBitmap = loadBitmap(c.getString("hyperlink"));
Bitmap newBitmap2 = ImageLoader.getInstance().loadImageSync(c.getString("hyperlink"));
Log.i("INFO", "Hyperlink: " + c.getString("hyperlink"));
map.put("ImageThumBitmap", newBitmap2);
map.put("Repeat", "1"); //To know if it is a new photo
} else {
// no new photo
map.put("Repeat", "0");
Log.i("INFO", "Inside else");
}
photo_id_prev = photo_id_new;
Log.i("INFO", "Previous photo id: "+photo_id_prev);
MyArrList.add(map);
publishProgress(i);
}
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalStateException e){
e.printStackTrace();
}
return null;
}
@Override
public void onProgressUpdate(Integer... progress) {
imageAdapter.notifyDataSetChanged();
}
@Override
protected void onPostExecute(Object result) {
setProgressBarIndeterminateVisibility(false); // When Finish
}
}
public class ImageAdapter extends BaseAdapter {
private Context mContext;
public ImageAdapter(Context context) {
mContext = context;
}
public int getCount() {
return MyArrList.size();
}
public Object getItem(int position) {
return MyArrList.get(position);
}
public long getItemId(int position) {
return position;
}
public View getView(int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
//View row = convertView;
ViewHolder holder;
DisplayImageOptions options = new DisplayImageOptions.Builder()
.resetViewBeforeLoading(true)
.cacheInMemory(true)
.cacheOnDisc(true)
.bitmapConfig(Bitmap.Config.RGB_565) // default
.displayer(new SimpleBitmapDisplayer())
.imageScaleType(ImageScaleType.EXACTLY)
.build();
ImageLoaderConfiguration config = new ImageLoaderConfiguration.Builder(getApplicationContext())
.threadPriority(Thread.MAX_PRIORITY).threadPoolSize(5)
.denyCacheImageMultipleSizesInMemory()
.memoryCache(new UsingFreqLimitedMemoryCache(6 * 1024 * 1024))
.discCacheFileNameGenerator(new Md5FileNameGenerator())
.tasksProcessingOrder(QueueProcessingType.LIFO)
.build();
ImageLoader.getInstance().init(config);
Object repeat = MyArrList.get(position).get("Repeat");
DisplayMetrics metrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(metrics);
int height = metrics.heightPixels;
int width = metrics.widthPixels;
//Try when row = null
if (convertView == null) {
LayoutInflater inflater = (LayoutInflater) mContext
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = inflater.inflate(R.layout.activity_column, null);
holder = new ViewHolder();
holder.imageView = (ImageView) convertView.findViewById(R.id.ColImgPath);
holder.tvUsername = (TextView) convertView.findViewById(R.id.tVforename);
holder.tvUserSurname = (TextView) convertView.findViewById(R.id.tVsurname);
holder.ivProfilePhoto = (ImageView) convertView.findViewById(R.id.pphoto);
holder.tvNameAcc = (TextView) convertView.findViewById(R.id.N);
holder.tvBrandAcc = (TextView) convertView.findViewById(R.id.B);
holder.tvPriceAcc = (TextView) convertView.findViewById(R.id.P);
holder.tvShopAcc = (TextView) convertView.findViewById(R.id.S);
convertView.setTag(holder);
}
else{
holder = (ViewHolder) convertView.getTag();
}
String url = (MyArrList.get(position).get("ImageThumBitmap").toString());
// ColImage
holder.imageView.setPadding(5, 5, 5, 5);
//holder.imageView.setScaleType(ImageView.ScaleType.CENTER);
holder.imageView.setRotation(90);
//Depends on the photo show or hidden the name and surname
if(repeat.equals("1")){
holder.imageView.setVisibility(View.VISIBLE);
holder.tvUserSurname.setVisibility(View.VISIBLE);
holder.tvUsername.setVisibility(View.VISIBLE);
holder.tvUserSurname.setText(MyArrList.get(position).get("UserSurname").toString());
holder.tvUsername.setText(MyArrList.get(position).get("UserName").toString());
try {
//Bitmap bmp = ((Bitmap) MyArrList.get(position).get("ImageThumBitmap"));
//int size = Math.min(bmp.getWidth(), bmp.getHeight());
//int x = (bmp.getWidth() - size) / 16;
//int y = (bmp.getHeight() - size) / 9;
//Bitmap result = bmp.createBitmap(bmp, x, y, size, size);
//Bitmap photobitmap1 = Bitmap.createScaledBitmap(bmp, width/2, height/2, true);
//holder.imageView.setImageBitmap(bmp);
ImageLoader.getInstance().displayImage(url, holder.imageView);
//holder.imageView.setImageBitmap((Bitmap) MyArrList.get(position).get("ImageThumBitmap"));
} catch (Exception e) {
// When Error
holder.imageView.setImageResource(android.R.drawable.ic_menu_report_image);
}
}
else {
//If the photo_id is repeated these params are not shown
holder.tvUserSurname.setVisibility(View.GONE);
holder.tvUsername.setVisibility(View.GONE);
holder.imageView.setVisibility(View.GONE);
}
// ColNameAcc
holder.tvNameAcc.setPadding(20, 0, 0, 0);
holder.tvNameAcc.setText(MyArrList.get(position).get("NameAcc").toString());
// ColBrandAcc
holder.tvBrandAcc.setPadding(20, 0, 0, 0);
holder.tvBrandAcc.setText(MyArrList.get(position).get("BrandAcc").toString());
// ColPriceAcc
holder.tvPriceAcc.setPadding(20, 0, 0, 0);
holder.tvPriceAcc.setText(MyArrList.get(position).get("PriceAcc").toString()
// ColShopAcc
holder.tvShopAcc.setPadding(20, 0, 0, 0);
holder.tvShopAcc.setText(MyArrList.get(position).get("Shopname").toString());
return convertView;
}
}
public static class ViewHolder {
ImageView imageView;
TextView tvUsername;
TextView tvUserSurname;
ImageView ivProfilePhoto;
TextView tvNameAcc;
TextView tvBrandAcc;
TextView tvPriceAcc;
TextView tvShopAcc;
}
}
Logcat错误：
05-20 13:52:50.496 6524-3500/com.AndroidUK.SocialApp.app E/AndroidRuntime﹕ FATAL EXCEPTION: AsyncTask #4
Process: com.AndroidUK.SocialApp.app, PID: 6524
java.lang.RuntimeException: An error occured while executing doInBackground()
at android.os.AsyncTask$3.done(AsyncTask.java:300)
at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
at java.util.concurrent.FutureTask.setException(FutureTask.java:222)
at java.util.concurrent.FutureTask.run(FutureTask.java:242)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
at java.lang.Thread.run(Thread.java:841)
Caused by: android.view.ViewRootImpl$CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views.
at android.view.ViewRootImpl.checkThread(ViewRootImpl.java:6094)
at android.view.ViewRootImpl.requestLayout(ViewRootImpl.java:824)
at android.view.View.requestLayout(View.java:16455)
at android.view.View.requestLayout(View.java:16455)
at android.view.View.requestLayout(View.java:16455)
at android.view.View.requestLayout(View.java:16455)
at android.view.View.requestLayout(View.java:16455)
at android.view.View.requestLayout(View.java:16455)
at android.widget.AbsListView.requestLayout(AbsListView.java:1916)
at android.widget.AdapterView$AdapterDataSetObserver.onChanged(AdapterView.java:814)
at android.widget.AbsListView$AdapterDataSetObserver.onChanged(AbsListView.java:6280)
at android.database.DataSetObservable.notifyChanged(DataSetObservable.java:37)
at android.widget.BaseAdapter.notifyDataSetChanged(BaseAdapter.java:50)
at com.AndroidUK.SocialApp.app.Listview$LoadContentFromServer.doInBackground(Listview.java:212)
at android.os.AsyncTask$2.call(AsyncTask.java:288)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
在android.os.AsyncTask $ SerialExecutor $ 1.run（AsyncTask.java:231） at java.util.concurrent.ThreadPoolExecutor.runWorker（ThreadPoolExecutor.java:1112） at java.util.concurrent.ThreadPoolExecutor $ Worker.run（ThreadPoolExecutor.java:587） 在java.lang.Thread.run（Thread.java:841）
另外我有一个问题是刷新我的listview，因为数据来自数据库，我不知道如何通知有新照片。有时应用关闭，因为我上传了一张新照片。当我上传照片而没有关闭应用程序时，我会查看列表视图。
由于
答案 0 :(得分：0)
您正在非主线程中调用 imageAdapter.notifyDataSetChanged（），例如 onPostExecute（）。 onPostExecute（）是执行UI操作，更新等的方法。 doInBackground（），正如名称所示，它只执行后台操作，例如从中访问数据文件，网络等