我正在制作一个模块，可以将所有文件从保管箱上的应用程序文件夹下载到设备。
现在，我正在使用 Core API 下载文件。一切正常。但是对于多个文件，我不知道当前文件何时完成下载以转到下一个文件。
这是我的下载代码：
final String cachePath = FileHandler.ROOT_LOCAL_FOLDER_DIR + "/" + mFile.getFileName();
try {
mFos = new FileOutputStream(cachePath);
} catch (FileNotFoundException e) {
mErrorMsg = "Couldn't create a local file to store the image";
return false;
}
ProgressListener mProgressLisenter = new ProgressListener() {
@Override
public void onProgress(long arg0, long arg1) {
// TODO Auto-generated method stub
tmpFile = new File(cachePath);
OnDownloadProgressDropboxChecked(FileHandler.PROGRESS_STATUS_ONPROGRESS, (int) (arg0 * 100 / arg1));
}
@Override
public long progressInterval() {
return 100;
}
};
mDownloaded = mApi.getFile(mFile.getFileId(), null, mFos, mProgressLisenter);
OnDownloadDropboxChecked(TRUE, "Download complete");
} catch (DropboxUnlinkedException e) {
mErrorMsg = "Unlinked";
} catch (DropboxPartialFileException e) {
// We canceled the operation
mErrorMsg = "Download canceled";
} catch (DropboxServerException e) {
}
}
我试过了：
- 捕获进度下载，当达到 100% 时通知 - 这样，Dropbox 的 OnProgress 不会立即显示，有时它不会达到 100%
- 把它放在异步任务中 - 没用
我现在一头雾水，任何进步对我都有好处。
编辑：
解决方案是在 getFile() 下放置一些触发器，然后它可以工作。
这是我的完整课程：
public class DownloadFile extends AsyncTask<Void, Long, Boolean> implements DConst {
Context act;
private DropboxAPI<?> mApi;
// private String mPath;
private FileOutputStream mFos;
private boolean mCanceled;
private Long mFileLen;
private String mErrorMsg;
private String mFileName;
String path;
DFile mFile;
DropboxAPI.DropboxFileInfo mDownloaded;
@SuppressWarnings("deprecation")
public DownloadFile(Context act, DropboxAPI<?> api, DFile mDFile) {
// We set the context this way so we don't accidentally leak activities
this.act = act;
mApi = api;
mFile = mDFile;
path = mDFile.getFileId();
mFileName = mDFile.getFileName();
OnDownloadProgressDropboxChecked(FileHandler.PROGRESS_STATUS_START, 0);
}
File tmpFile;
@Override
protected Boolean doInBackground(Void... params) {
try {
final String cachePath = FileHandler.ROOT_LOCAL_FOLDER_DIR + "/" + mFile.getFileName();
try {
mFos = new FileOutputStream(cachePath);
} catch (FileNotFoundException e) {
mErrorMsg = "Couldn't create a local file to store the image";
return false;
}
ProgressListener mProgressLisenter = new ProgressListener() {
@Override
public void onProgress(long arg0, long arg1) {
// TODO Auto-generated method stub
tmpFile = new File(cachePath);
OnDownloadProgressDropboxChecked(FileHandler.PROGRESS_STATUS_ONPROGRESS, (int) (arg0 * 100 / arg1));
Log.d("Dolphin got interval", String.valueOf(tmpFile.length() + " - " + arg0 + " - " + arg1));
}
@Override
public long progressInterval() {
return 100;
}
};
mDownloaded = mApi.getFile(mFile.getFileId(), null, mFos, mProgressLisenter);
} catch (DropboxUnlinkedException e) {
mErrorMsg = "Unlinked";
} catch (DropboxPartialFileException e) {
// We canceled the operation
mErrorMsg = "Download canceled";
} catch (DropboxServerException e) {
// Server-side exception. These are examples of what could happen,
// but we don't do anything special with them here.
if (e.error == DropboxServerException._304_NOT_MODIFIED) {
// won't happen since we don't pass in revision with metadata
} else if (e.error == DropboxServerException._401_UNAUTHORIZED) {
// Unauthorized, so we should unlink them. You may want to
// automatically log the user out in this case.
} else if (e.error == DropboxServerException._403_FORBIDDEN) {
// Not allowed to access this
} else if (e.error == DropboxServerException._404_NOT_FOUND) {
// path not found (or if it was the thumbnail, can't be
// thumbnailed)
} else if (e.error == DropboxServerException._406_NOT_ACCEPTABLE) {
// too many entries to return
} else if (e.error == DropboxServerException._415_UNSUPPORTED_MEDIA) {
// can't be thumbnailed
} else if (e.error == DropboxServerException._507_INSUFFICIENT_STORAGE) {
// user is over quota
} else {
// Something else
}
// This gets the Dropbox error, translated into the user's language
mErrorMsg = e.body.userError;
if (mErrorMsg == null) {
mErrorMsg = e.body.error;
}
} catch (DropboxIOException e) {
// Happens all the time, probably want to retry automatically.
mErrorMsg = "Network error. Try again.";
} catch (DropboxParseException e) {
// Probably due to Dropbox server restarting, should retry
mErrorMsg = "Dropbox error. Try again.";
} catch (DropboxException e) {
// Unknown error
mErrorMsg = "Unknown error. Try again.";
} finally {
if (mFos != null) {
try {
mFos.close();
return true;
} catch (IOException e) {
}
}
}
return false;
}
@Override
protected void onPostExecute(Boolean result) {
OnDownloadProgressDropboxChecked(FileHandler.PROGRESS_STATUS_FINISH, 0);
if (result) {
OnDownloadDropboxChecked(TRUE, "Download complete");
} else {
OnDownloadDropboxChecked(FALSE, mErrorMsg);
}
}
OnAsyncDownloadListener onAsyncDownloadListener;
OnAsyncDownloadProgressListener onAsyncDownloadProgressListener;
private void OnDownloadDropboxChecked(int res, String messenger) {
if (onAsyncDownloadListener != null) {
onAsyncDownloadListener.OnAsyncDownload(res, messenger);
}
}
private void OnDownloadProgressDropboxChecked(int status, int percent) {
if (onAsyncDownloadProgressListener != null) {
onAsyncDownloadProgressListener.OnAsyncDownloadProgress(status, percent);
}
}
public void setOnAsyncDownloadListener(OnAsyncDownloadListener listener) {
onAsyncDownloadListener = listener;
}
public void setOnAsyncDownloadProgressListener(OnAsyncDownloadProgressListener listener) {
onAsyncDownloadProgressListener = listener;
}
public interface OnAsyncDownloadListener {
public abstract void OnAsyncDownload(int res, String messenger);
}
public interface OnAsyncDownloadProgressListener {
public abstract void OnAsyncDownloadProgress(int status, int percent);
}
}
由 Asynctask 的“OnDownloadDropboxChecked()”引起的错误在 getFile() 之前触发。所以它返回一个错误的通知。