我正在使用Parse SDK在Android Studio中制作应用。当我在模拟器上运行设备时，它工作正常。在实际设备上，它不会显示图像。这是代码：
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.ic_launcher;
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) {
final 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.
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();
}
还有一个例外情况可以显示正在发生的事情。
java.io.FileNotFoundException: /storage/emulated/0/AggiesLand/878582989: open failed: ENOENT (No such file or directory)
有没有办法在实际设备上显示图像？
编辑：这是logcat
06-26 17：52：56.778 21588-22075 / com.lbbw.AggiesLand.aggiesland.app W / System.err：java.io.FileNotFoundException：/ storage / emulated / 0 / AggiesLand / 878582989：open failed： ENOENT（没有这样的文件或目录） 06-26 17：52：56.778 21588-22075 / com.lbbw.AggiesLand.aggiesland.app W / System.err：at libcore.io.IoBridge.open（IoBridge.java:409） 06-26 17：52：56.778 21588-22075 / com.lbbw.AggiesLand.aggiesland.app W / System.err：at java.io.FileOutputStream。（FileOutputStream.java:88） 06-26 17：52：56.778 21588-22075 / com.lbbw.AggiesLand.aggiesland.app W / System.err：at java.io.FileOutputStream。（FileOutputStream.java:73） 06-26 17：52：56.778 21588-22075 / com.lbbw.AggiesLand.aggiesland.app W / System.err：at com.lbbw.AggiesLand.aggiesland.app.ImageLoader.getBitmap（ImageLoader.java:78） 06-26 17：52：56.778 21588-22075 / com.lbbw.AggiesLand.aggiesland.app W / System.err：at com.lbbw.AggiesLand.aggiesland.app.ImageLoader.access $ 000（ImageLoader.java:28） 06-26 17：52：56.778 21588-22075 / com.lbbw.AggiesLand.aggiesland.app W / System.err：at com.lbbw.AggiesLand.aggiesland.app.ImageLoader $ PhotosLoader.run（ImageLoader.java:152） 06-26 17：52：56.778 21588-22075 / com.lbbw.AggiesLand.aggiesland.app W / System.err：at java.util.concurrent.Executors $ RunnableAdapter.call（Executors.java:422） 06-26 17：52：56.778 21588-22075 / com.lbbw.AggiesLand.aggiesland.app W / System.err：at java.util.concurrent.FutureTask.run（FutureTask.java:237） 06-26 17：52：56.778 21588-22075 / com.lbbw.AggiesLand.aggiesland.app W / System.err：at java.util.concurrent.ThreadPoolExecutor.runWorker（ThreadPoolExecutor.java:1112） 06-26 17：52：56.778 21588-22075 / com.lbbw.AggiesLand.aggiesland.app W / System.err：at java.util.concurrent.ThreadPoolExecutor $ Worker.run（ThreadPoolExecutor.java:587） 06-26 17：52：56.778 21588-22075 / com.lbbw.AggiesLand.aggiesland.app W / System.err：at java.lang.Thread.run（Thread.java:841） 06-26 17：52：56.788 21588-22075 / com.lbbw.AggiesLand.aggiesland.app W / System.err：引起：libcore.io.ErrnoException：open failed：ENOENT（没有这样的文件或目录） 06-26 17：52：56.788 21588-22079 / com.lbbw.AggiesLand.aggiesland.app W / System.err：java.io.FileNotFoundException：/ storage / emulated / 0 / AggiesLand / -1260189210：open failed：ENOENT（没有相应的文件和目录） 06-26 17：52：56.788 21588-22079 / com.lbbw.AggiesLand.aggiesland.app W / System.err：at libcore.io.IoBridge.open（IoBridge.java:409） 06-26 17：52：56.788 21588-22079 / com.lbbw.AggiesLand.aggiesland.app W / System.err：at java.io.FileOutputStream。（FileOutputStream.java:88） 06-26 17：52：56.788 21588-22075 / com.lbbw.AggiesLand.aggiesland.app W / System.err：at at libcore.io.Posix.open（Native Method） 06-26 17：52：56.788 21588-22079 / com.lbbw.AggiesLand.aggiesland.app W / System.err：at java.io.FileOutputStream。（FileOutputStream.java:73） 06-26 17：52：56.788 21588-22075 / com.lbbw.AggiesLand.aggiesland.app W / System.err：at libcore.io.BlockGuardOs.open（BlockGuardOs.java:110） 06-26 17：52：56.788 21588-22075 / com.lbbw.AggiesLand.aggiesland.app W / System.err：at libcore.io.IoBridge.open（IoBridge.java:393） 06-26 17：52：56.788 21588-22075 / com.lbbw.AggiesLand.aggiesland.app W / System.err：... 10 more 06-26 17：52：56.788 21588-22079 / com.lbbw.AggiesLand.aggiesland.app W / System.err：com.lbbw.AggiesLand.aggiesland.app.ImageLoader.getBitmap（ImageLoader.java:78）