ImageLoader的不加载真实设备映像 [英] Imageloader not loading image on real device
本文介绍了ImageLoader的不加载真实设备映像的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我使用ImageLoader的类来从URL加载图像，并在显示它
列表显示。但是，这ImageLoader的加载模拟器上的形象，当我
它不加载任何图像的实际设备上运行我的应用程序。（只显示
默认图像）。
请告诉我，我有什么用ImageLoader的类做的就是它的工作在真实设备上。
ImageLoader的类：
公共类ImageLoader的{ 的MemoryCache的MemoryCache =新的MemoryCache（）;
FileCache fileCache;
私人地图＆LT; ImageView的，字符串＆GT; imageViews =集合
.synchronizedMap（新的WeakHashMap＆LT; ImageView的，字符串＆GT;（））;
ExecutorService的ExecutorService的;
//处理程序，以显示在UI线程图片
处理程序处理程序=新的处理程序（）; 公共ImageLoader的（上下文的背景下）{
fileCache =新FileCache（背景）;
ExecutorService的= Executors.newFixedThreadPool（5）;
} 最终诠释stub_id = R.drawable.products; 公共无效DisplayImage（字符串URL，ImageView的ImageView的）{
imageViews.put（ImageView的，URL）;
位图位图= memoryCache.get（URL）;
如果（位图！= NULL）
imageView.setImageBitmap（位图）;
其他{
queuePhoto（URL，ImageView的）;
imageView.setImageResource（stub_id）;
}
} 私人无效queuePhoto（字符串URL，ImageView的ImageView的）{
PhotoToLoad P =新PhotoToLoad（URL，ImageView的）;
executorService.submit（新PhotosLoader（P））;
} 私人位图getBitmap（字符串URL）{
文件F = fileCache.getFile（URL）; 位图B =去codeFILE（F）;
如果（B！= NULL）
返回b; 从网上下载//图片
尝试{
位图位图= NULL;
URL =图片网址新的URL（网址）;
HttpURLConnection的康恩=（HttpURLConnection类）图片网址
.openConnection（）;
conn.setConnectTimeout（30000）;
conn.setReadTimeout（30000）;
conn.setInstanceFollowRedirects（真）;
InputStream为= conn.getInputStream（）;
OutputStream的OS =新的FileOutputStream（F）;
Utils.CopyStream（是，OS）;
os.close（）;
conn.disconnect（）;
位=去codeFILE（F）;
返回位图;
}赶上（Throwable的前）{
ex.printStackTrace（）;
如果（前的instanceof的OutOfMemoryError）
memoryCache.clear（）;
返回null;
}
} //德$ C $连拍影像的鳞它来减少内存消耗
私人位图德codeFILE（文件f）{
尝试{
//德code图像尺寸
BitmapFactory.Options O =新BitmapFactory.Options（）;
o.inJustDe codeBounds = TRUE;
的FileInputStream流1 =新的FileInputStream（F）;
BitmapFactory.de codeStream（STREAM1，空，O）;
stream1.close（）; //找到正确的比例值。它应该是2的幂。
//推荐大小512
最终诠释REQUIRED_SIZE = 70;
INT width_tmp = o.outWidth，height_tmp = o.outHeight;
int标= 1;
而（真）{
如果（width_tmp / 2'; REQUIRED_SIZE
|| height_tmp / 2'; REQUIRED_SIZE）
打破;
width_tmp / = 2;
height_tmp / = 2;
规模* = 2;
} //德code。与inSampleSize
BitmapFactory.Options O2 =新BitmapFactory.Options（）;
o2.inSampleSize =规模;
流2的FileInputStream =新的FileInputStream（F）;
位图位图= BitmapFactory.de codeStream（流2，空，O2）;
stream2.close（）;
返回位图;
}赶上（FileNotFoundException异常五）{
}赶上（IOException异常五）{
e.printStackTrace（）;
}
返回null;
} //任务队列
私有类PhotoToLoad {
公共字符串的URL;
公共ImageView的ImageView的; 公共PhotoToLoad（字符串U，ImageView的我）{
URL = U;
ImageView的= I;
}
} 类PhotosLoader实现Runnable {
PhotoToLoad photoToLoad; PhotosLoader（PhotoToLoad photoToLoad）{
this.photoToLoad = photoToLoad;
} @覆盖
公共无效的run（）{
尝试{
如果（imageViewReused（photoToLoad））
返回;
BMP位图= getBitmap（photoToLoad.url）;
memoryCache.put（photoToLoad.url，BMP）;
如果（imageViewReused（photoToLoad））
返回;
BitmapDisplayer BD =新BitmapDisplayer（BMP，photoToLoad）;
handler.post（BD）;
}赶上（的Throwable日）{
th.printStackTrace（）;
}
}
} 布尔imageViewReused（PhotoToLoad photoToLoad）{
字符串标记= imageViews.get（photoToLoad.imageView）;
如果（标记== NULL ||！tag.equals（photoToLoad.url））
返回true;
返回false;
} //用在UI线程来显示位图
类BitmapDisplayer实现Runnable {
位图位图;
PhotoToLoad photoToLoad; 公共BitmapDisplayer（位图B，PhotoToLoad P）{
位= B;
photoToLoad = P;
} 公共无效的run（）{
如果（imageViewReused（photoToLoad））
返回;
如果（位图！= NULL）
photoToLoad.imageView.setImageBitmap（位图）;
其他
photoToLoad.imageView.setImageResource（stub_id）;
}
} 公共无效clearCache（）{
memoryCache.clear（）;
fileCache.clear（）;
}}
我GalleryTab类别： -
公共类GalleryTab扩展片段{
GridView控件GridView控件;
ProgressDialog mProgressDialog;
GridViewAdapter适配器;
公开名单＆LT; GalleryList＆GT; phonearraylist = NULL;
查看视图。
私人的WeakReference＆LT; RemoteDataTask＆GT; asyncTaskWeakRef; 公共静态的newInstance片段（上下文的背景下）{
GalleryTab F =新GalleryTab（）;
返回F;
} @覆盖
公共查看onCreateView（LayoutInflater充气器，容器的ViewGroup，
捆绑savedInstanceState）{
//充气的布局该片段
鉴于= inflater.inflate（R.layout.activity_gallery_tab，NULL）;
GridView控件=（GridView控件）view.findViewById（R.id.gridview）;
setRetainInstance（真）;
startNewAsyncTask（）;
//新RemoteDataTask（本）.execute（）;
返回视图。
} // RemoteDataTask的AsyncTask
私有类RemoteDataTask扩展的AsyncTask＆LT;太虚，太虚，太虚＆GT; {
私人的WeakReference＆LT; GalleryTab＆GT; fragmentWeakRef; 私人RemoteDataTask（GalleryTab gallerytab）{
this.fragmentWeakRef =新的WeakReference＆LT; GalleryTab＆GT;（gallerytab）;
} @覆盖
在preExecute保护无效（）{
super.on preExecute（）;
mProgressDialog =新ProgressDialog（getActivity（））;
mProgressDialog.setTitle（库）;
mProgressDialog.setMessage（正在加载...）;
mProgressDialog.setIndeterminate（假）;
mProgressDialog.show（）;
} @覆盖
保护无效doInBackground（虚空...... PARAMS）{
//创建数组 phonearraylist =新的ArrayList＆LT; GalleryList＆GT;（）;
尝试{
的for（int i = 0; I＆LT; = 6;我++）{
GalleryList地图=新GalleryList（）;
map.setGallery（http://oi39.tinypic.com/21oydxs.jpg）;
//的System.out.println（打印!!!! - + I）;
phonearraylist.add（地图）;
}
}赶上（ParseException的E）{
Log.e（错误，e.getMessage（））;
e.printStackTrace（）;
} 返回null;
} @覆盖
保护无效onPostExecute（虚空结果）{
super.onPostExecute（结果）;
//如果（this.fragmentWeakRef.get（）！= NULL）{
适配器=新GridViewAdapter（getActivity（），phonearraylist）;
//的System.out.println（打印尺寸 - + phonearraylist.size（））;
gridview.setAdapter（适配器）; mProgressDialog.dismiss（）;
//}
}
} 私人无效startNewAsyncTask（）{
RemoteDataTask的AsyncTask =新RemoteDataTask（本）;
this.asyncTaskWeakRef =新的WeakReference＆LT; RemoteDataTask＆GT;（AsyncTask的）;
asyncTask.execute（）;
}
}
我GridViewAdapter类别： -
公共类GridViewAdapter延伸BaseAdapter { //声明变量
上下文语境;
LayoutInflater吹气;
ImageLoader的ImageLoader的;
私人列表＆LT; GalleryList＆GT; galleryArraylist = NULL;
私人的ArrayList＆LT; GalleryList＆GT; ArrayList的; 公共GridViewAdapter（上下文的背景下，列表与LT; GalleryList＆GT; phonearraylist）{
this.context =背景;
this.galleryArraylist = phonearraylist;
充气= LayoutInflater.from（上下文）;
this.arraylist =新的ArrayList＆LT; GalleryList＆GT;（）;
this.arraylist.addAll（phonearraylist）;
ImageLoader的=新ImageLoader的（上下文）;
} 公共类ViewHolder {
ImageView的电话;
} @覆盖
公众诠释的getCount（）{
返回galleryArraylist.size（）;
} @覆盖
公共对象的getItem（INT位置）{
返回galleryArraylist.get（位置）;
} @覆盖
众长getItemId（INT位置）{
返回的位置;
} 公共查看getView（最终诠释的立场，观点来看，一个ViewGroup父）{
最后ViewHolder持有人;
如果（查看== NULL）{
持有人=新ViewHolder（）;
鉴于= inflater.inflate（R.layout.gridview_item，NULL）;
//定位gridview_item.xml的ImageView的
holder.phone =（ImageView的）view.findViewById（R.id.phone）;
view.setTag（保持器）;
}其他{
支架=（ViewHolder）view.getTag（）;
}
//设置成果转化的ImageView
imageLoader.DisplayImage（galleryArraylist.get（位置）.getGallery（）
holder.phone）;
//监听GridView的项目请点击
view.setOnClickListener（新OnClickListener（）{ @覆盖
公共无效的onClick（查看为arg0）{
//单个项目的点击数据发送到SingleItemView类
意向意图=新意图（背景下，SingleItemView.class）;
//把所有的数据电话
intent.putExtra（长廊，
（galleryArraylist.get（位置）.getGallery（）））;
//开始SingleItemView类
context.startActivity（意向）;
}
}）;
返回视图。
}
}
解决方案检查清单所需的权限。
I am using ImageLoader class to load an image from an url and displaying it in a list view. But this ImageLoader is loading the image on an emulator, when I run my app on a real device it's not loading any image.(Just showing the default image).
Please tell me what I have to do with the ImageLoader class to get it working on a real device.
ImageLoader Class:
public class ImageLoader { MemoryCache memoryCache = new MemoryCache(); FileCache fileCache; private Map<ImageView, String> imageViews = Collections .synchronizedMap(new WeakHashMap<ImageView, String>()); ExecutorService executorService; // Handler to display images in UI thread Handler handler = new Handler(); public ImageLoader(Context context) { fileCache = new FileCache(context); executorService = Executors.newFixedThreadPool(5); } final int stub_id = R.drawable.products; public void DisplayImage(String url, ImageView imageView) { imageViews.put(imageView, url); Bitmap bitmap = memoryCache.get(url); if (bitmap != null) imageView.setImageBitmap(bitmap); else { queuePhoto(url, imageView); imageView.setImageResource(stub_id); } } private void queuePhoto(String url, ImageView imageView) { PhotoToLoad p = new PhotoToLoad(url, imageView); executorService.submit(new PhotosLoader(p)); } private Bitmap getBitmap(String url) { File f = fileCache.getFile(url); Bitmap b = decodeFile(f); if (b != null) return b; // Download Images from the Internet try { Bitmap bitmap = null; URL imageUrl = new URL(url); HttpURLConnection conn = (HttpURLConnection) imageUrl .openConnection(); conn.setConnectTimeout(30000); conn.setReadTimeout(30000); conn.setInstanceFollowRedirects(true); InputStream is = conn.getInputStream(); OutputStream os = new FileOutputStream(f); Utils.CopyStream(is, os); os.close(); conn.disconnect(); bitmap = decodeFile(f); return bitmap; } catch (Throwable ex) { ex.printStackTrace(); if (ex instanceof OutOfMemoryError) memoryCache.clear(); return null; } } // Decodes image and scales it to reduce memory consumption private Bitmap decodeFile(File f) { try { // Decode image size BitmapFactory.Options o = new BitmapFactory.Options(); o.inJustDecodeBounds = true; FileInputStream stream1 = new FileInputStream(f); BitmapFactory.decodeStream(stream1, null, o); stream1.close(); // Find the correct scale value. It should be the power of 2. // Recommended Size 512 final int REQUIRED_SIZE = 70; int width_tmp = o.outWidth, height_tmp = o.outHeight; int scale = 1; while (true) { if (width_tmp / 2 < REQUIRED_SIZE || height_tmp / 2 < REQUIRED_SIZE) break; width_tmp /= 2; height_tmp /= 2; scale *= 2; } // Decode with inSampleSize BitmapFactory.Options o2 = new BitmapFactory.Options(); o2.inSampleSize = scale; FileInputStream stream2 = new FileInputStream(f); Bitmap bitmap = BitmapFactory.decodeStream(stream2, null, o2); stream2.close(); return bitmap; } catch (FileNotFoundException e) { } catch (IOException e) { e.printStackTrace(); } return null; } // Task for the queue private class PhotoToLoad { public String url; public ImageView imageView; public PhotoToLoad(String u, ImageView i) { url = u; imageView = i; } } class PhotosLoader implements Runnable { PhotoToLoad photoToLoad; PhotosLoader(PhotoToLoad photoToLoad) { this.photoToLoad = photoToLoad; } @Override public void run() { try { if (imageViewReused(photoToLoad)) return; Bitmap bmp = getBitmap(photoToLoad.url); memoryCache.put(photoToLoad.url, bmp); if (imageViewReused(photoToLoad)) return; BitmapDisplayer bd = new BitmapDisplayer(bmp, photoToLoad); handler.post(bd); } catch (Throwable th) { th.printStackTrace(); } } } boolean imageViewReused(PhotoToLoad photoToLoad) { String tag = imageViews.get(photoToLoad.imageView); if (tag == null || !tag.equals(photoToLoad.url)) return true; return false; } // Used to display bitmap in the UI thread class BitmapDisplayer implements Runnable { Bitmap bitmap; PhotoToLoad photoToLoad; public BitmapDisplayer(Bitmap b, PhotoToLoad p) { bitmap = b; photoToLoad = p; } public void run() { if (imageViewReused(photoToLoad)) return; if (bitmap != null) photoToLoad.imageView.setImageBitmap(bitmap); else photoToLoad.imageView.setImageResource(stub_id); } } public void clearCache() { memoryCache.clear(); fileCache.clear(); } }
My GalleryTab Class:--
public class GalleryTab extends Fragment { GridView gridview; ProgressDialog mProgressDialog; GridViewAdapter adapter; public List<GalleryList> phonearraylist = null; View view; private WeakReference<RemoteDataTask> asyncTaskWeakRef; public static Fragment newInstance(Context context) { GalleryTab f = new GalleryTab(); return f; } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { // Inflate the layout for this fragment view = inflater.inflate(R.layout.activity_gallery_tab, null); gridview = (GridView) view.findViewById(R.id.gridview); setRetainInstance(true); startNewAsyncTask(); // new RemoteDataTask(this).execute(); return view; } // RemoteDataTask AsyncTask private class RemoteDataTask extends AsyncTask<Void, Void, Void> { private WeakReference<GalleryTab> fragmentWeakRef; private RemoteDataTask(GalleryTab gallerytab) { this.fragmentWeakRef = new WeakReference<GalleryTab>(gallerytab); } @Override protected void onPreExecute() { super.onPreExecute(); mProgressDialog = new ProgressDialog(getActivity()); mProgressDialog.setTitle("Gallery"); mProgressDialog.setMessage("Loading..."); mProgressDialog.setIndeterminate(false); mProgressDialog.show(); } @Override protected Void doInBackground(Void... params) { // Create the array phonearraylist = new ArrayList<GalleryList>(); try { for (int i = 0; i <= 6; i++) { GalleryList map = new GalleryList(); map.setGallery("http://oi39.tinypic.com/21oydxs.jpg"); // System.out.println("PRINT!!!!-- "+ i); phonearraylist.add(map); } } catch (ParseException e) { Log.e("Error", e.getMessage()); e.printStackTrace(); } return null; } @Override protected void onPostExecute(Void result) { super.onPostExecute(result); // if (this.fragmentWeakRef.get() != null) { adapter = new GridViewAdapter(getActivity(), phonearraylist); // System.out.println("PRINT SIZE -- "+ phonearraylist.size()); gridview.setAdapter(adapter); mProgressDialog.dismiss(); // } } } private void startNewAsyncTask() { RemoteDataTask asyncTask = new RemoteDataTask(this); this.asyncTaskWeakRef = new WeakReference<RemoteDataTask>(asyncTask); asyncTask.execute(); } }
My GridViewAdapter Class:-
public class GridViewAdapter extends BaseAdapter { // Declare Variables Context context; LayoutInflater inflater; ImageLoader imageLoader; private List<GalleryList> galleryArraylist = null; private ArrayList<GalleryList> arraylist; public GridViewAdapter(Context context, List<GalleryList> phonearraylist) { this.context = context; this.galleryArraylist = phonearraylist; inflater = LayoutInflater.from(context); this.arraylist = new ArrayList<GalleryList>(); this.arraylist.addAll(phonearraylist); imageLoader = new ImageLoader(context); } public class ViewHolder { ImageView phone; } @Override public int getCount() { return galleryArraylist.size(); } @Override public Object getItem(int position) { return galleryArraylist.get(position); } @Override public long getItemId(int position) { return position; } public View getView(final int position, View view, ViewGroup parent) { final ViewHolder holder; if (view == null) { holder = new ViewHolder(); view = inflater.inflate(R.layout.gridview_item, null); // Locate the ImageView in gridview_item.xml holder.phone = (ImageView) view.findViewById(R.id.phone); view.setTag(holder); } else { holder = (ViewHolder) view.getTag(); } // Set the results into ImageView imageLoader.DisplayImage(galleryArraylist.get(position).getGallery(), holder.phone); // Listen for GridView Item Click view.setOnClickListener(new OnClickListener() { @Override public void onClick(View arg0) { // Send single item click data to SingleItemView Class Intent intent = new Intent(context, SingleItemView.class); // Pass all data phone intent.putExtra("gallery", (galleryArraylist.get(position).getGallery())); // Start SingleItemView Class context.startActivity(intent); } }); return view; } }
解决方案Check necessary permissions in the manifest .
这篇关于ImageLoader的不加载真实设备映像的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
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