我正在从存储在数组中的 URL 加载 10 个图像。只有最后一个索引 url 在 SD 卡中加载和保存图像。这是我的代码：
for(int j=0; j<List.size();j++)
{
reviewImageLink =List.get(j).get(TAG_Image).toString();
URL reviewImageURL;
String name = reviewImageLink;//.substring(reviewImageLink .lastIndexOf("/") + 1,reviewImageLink.length());
try {
reviewImageURL = new URL(reviewImageLink);
if (!hasExternalStoragePublicPicture(name)) {
isImage = false;
new DownloadImageTask().execute(reviewImageURL);
Log.v("log_tag", "if");
isImage = true;
File sdImageMainDirectory = new File(Environment.getExternalStorageDirectory(), getResources().getString(R.string.directory));
//if(!sdImageMainDirectory.exists()){
sdImageMainDirectory.mkdirs();
File file = new File(sdImageMainDirectory, name);
Log.v("log_tag", "Directory created");}
}
catch (MalformedURLException e) {
Log.v(TAG, e.toString()); }
}
}//try
catch (Exception e) {
e.printStackTrace();}
DownloaderTask:
class DownloadImageTask extends AsyncTask<URL, Integer, Bitmap> {
// This class definition states that DownloadImageTask will take String
// parameters, publish Integer progress updates, and return a Bitmap
protected Bitmap doInBackground(URL... paths) {
URL url;
try {
url = paths[0];
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
int length = connection.getContentLength();
InputStream is = (InputStream) url.getContent();
byte[] imageData = new byte[length];
int buffersize = (int) Math.ceil(length / (double) 100);
int downloaded = 0;
int read;
while (downloaded < length) {
if (length < buffersize) {
read = is.read(imageData, downloaded, length);
} else if ((length - downloaded) <= buffersize) {
read = is.read(imageData, downloaded, length- downloaded);
} else {
read = is.read(imageData, downloaded, buffersize);
}
downloaded += read;
publishProgress((downloaded * 100) / length);
}
Bitmap bitmap = BitmapFactory.decodeByteArray(imageData, 0,length);
if (bitmap != null) {
Log.i(TAG, "Bitmap created");
} else {
Log.i(TAG, "Bitmap not created");
}
is.close();
return bitmap;
} catch (MalformedURLException e) {
Log.e(TAG, "Malformed exception: " + e.toString());
} catch (IOException e) {
Log.e(TAG, "IOException: " + e.toString());
} catch (Exception e) {
Log.e(TAG, "Exception: " + e.toString());
}
return null;
}
protected void onPostExecute(Bitmap result) {
String name = reviewImageLink.substring(reviewImageLink.lastIndexOf("/") + 1,reviewImageLink.length());
if (result != null) {
hasExternalStoragePublicPicture(name);
saveToSDCard(result, name);
isImage = true;
} else {
isImage = false;
}
}
}
public void saveToSDCard(Bitmap bitmap, String name) {
boolean mExternalStorageAvailable = false;
boolean mExternalStorageWriteable = false;
String state = Environment.getExternalStorageState();
if (Environment.MEDIA_MOUNTED.equals(state)) {
mExternalStorageAvailable = mExternalStorageWriteable = true;
Log.v(TAG, "SD Card is available for read and write "+ mExternalStorageAvailable + mExternalStorageWriteable);
saveFile(bitmap, name);
} else if (Environment.MEDIA_MOUNTED_READ_ONLY.equals(state)) {
mExternalStorageAvailable = true;
mExternalStorageWriteable = false;
Log.v(TAG, "SD Card is available for read "+ mExternalStorageAvailable);
} else {
mExternalStorageAvailable = mExternalStorageWriteable = false;
Log.v(TAG, "Please insert a SD Card to save your Video "+ mExternalStorageAvailable + mExternalStorageWriteable);
}
}
private void saveFile(Bitmap bitmap, String name)
{
String filename = name;
ContentValues values = new ContentValues();
File sdImageMainDirectory = new File(Environment.getExternalStorageDirectory(), getResources().getString(R.string.directory));
sdImageMainDirectory.mkdirs();
File outputFile = new File(sdImageMainDirectory, filename);
values.put(MediaStore.MediaColumns.DATA, outputFile.toString());
values.put(MediaStore.MediaColumns.TITLE, filename);
values.put(MediaStore.MediaColumns.DATE_ADDED, System.currentTimeMillis());
values.put(MediaStore.MediaColumns.MIME_TYPE, "output.jpeg");
Uri uri = this.getContentResolver().insert(android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI,values);
//Uri result = context.getContentResolver().insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, image);
sendBroadcast(new Intent(Intent.ACTION_MEDIA_MOUNTED, Uri.parse("file://"+ Environment.getExternalStorageDirectory())));
try
{
OutputStream outStream = this.getContentResolver().openOutputStream(uri);
bitmap.compress(Bitmap.CompressFormat.JPEG, 95, outStream);
outStream.flush();
outStream.close();
}
catch (FileNotFoundException e)
{
e.printStackTrace();
} catch (IOException e)
{
e.printStackTrace();
}
}
private boolean hasExternalStoragePublicPicture(String name) {
File sdImageMainDirectory = new File(Environment.getExternalStorageDirectory(), getResources().getString(R.string.directory));
File file = new File(sdImageMainDirectory, name);
if (file != null)
{
file.delete();
}
return file.exists();
}