我正在开发多个文件下载应用。其中，如果开关打开则开始下载，如果开关关闭，则取消下载。我正在使用带有处理程序的timertask更新项目值。下面是我的适配器代码。一切正常，但是当我滚动列表视图时，项目值（百分比计数）与其他文件下载进度的其他值冲突。
代码：
public class DownloadAdapter extends ArrayAdapter<AudioSubModel> {
private static final String PDF_MIME_TYPE = "application/pdf";
private LayoutInflater lf;
Context mContext;
private List<ListContent> lstHolders;
private Handler mHandler = new Handler();
private Runnable updateRemainingTimeRunnable = new Runnable() {
@Override
public void run() {
synchronized (lstHolders) {
for (ListContent holder : lstHolders) {
holder.updateTimeRemaining();
}
}
}
};
AudioSubModel getAlarm(int position){
return ((AudioSubModel) getItem(position));
}
public DownloadAdapter(Context context, int resource, List<AudioSubModel> objects) {
super(context, resource, objects);
lf = LayoutInflater.from(context);
lstHolders = new ArrayList<ListContent>();
mContext = context;
Log.e("ADAPTER", "CONSTR");
startUpdateTimer();
}
private void startUpdateTimer() {
Timer tmr = new Timer();
tmr.schedule(new TimerTask() {
@Override
public void run() {
mHandler.post(updateRemainingTimeRunnable);
}
}, 1000, 1000);
}
@Override
public View getView(int position, View view, ViewGroup parent) {
ListContent holder = null;
if (view == null) {
view = lf.inflate(R.layout.row_audio_desc_layout, null);
holder = new ListContent();
holder.ivImg = (CircleImageView)view.findViewById(R.id.row_audio_desc_ivImg);
holder.tvTitle = (TextView) view
.findViewById(R.id.row_audio_desc_tvTitle);
holder.tvDesc = (TextView) view
.findViewById(R.id.row_audio_desc_tvDesc);
holder.llDownload = (LinearLayout)view.findViewById(R.id.row_audio_desc_llDownload);
holder.PBDownload = (RoundCornerProgressBar)view.findViewById(R.id.row_audio_desc_PBDownload);
holder.tvReadPdf = (TextView)view.findViewById(R.id.row_audio_desc_tvReadPdf);
holder.tvMakeOffline = (TextView)view.findViewById(R.id.row_audio_desc_tvMakeOffline);
holder.swtchDownload = (Switch)view.findViewById(R.id.row_audio_desc_swtchDownloadOn);
holder.tvDownload = (TextView)view.findViewById(R.id.row_audio_desc_tvDownload);
holder.tvDownloadPercent = (TextView)view.findViewById(R.id.row_audio_desc_tvDownloadPercent);
holder.ivCancel = (ImageView)view.findViewById(R.id.row_audio_desc_ivCancel);
holder.ivPlay = (ImageView)view.findViewById(R.id.row_audio_desc_ivPlay);
holder.tvTitle.setTypeface(MyApplication.app_bold);
holder.tvDesc.setTypeface(MyApplication.app_light);
holder.tvReadPdf.setTypeface(MyApplication.app_bold);
holder.tvMakeOffline.setTypeface(MyApplication.app_bold);
holder.swtchDownload.setTypeface(MyApplication.app_bold);
holder.tvDownload.setTypeface(MyApplication.app_bold);
holder.tvDownloadPercent.setTypeface(MyApplication.app_bold);
view.setTag(holder);
synchronized (lstHolders) {
lstHolders.add(holder);
}
} else {
holder = (ListContent) view.getTag();
}
holder.setData(getAlarm(position));
// convertView.setOnClickListener(new View.OnClickListener() {
// @Override
// public void onClick(View v) {
// ((MainActivity)mContext).ItemClickFetch(getItem(position).getId());
// }
// });
return view;
}
class ListContent {
LinearLayout llDownload;
RoundCornerProgressBar PBDownload;
CircleImageView ivImg;
ImageView ivCancel, ivPlay;
TextView tvTitle, tvDesc, tvReadPdf, tvMakeOffline, tvDownload, tvDownloadPercent;
Switch swtchDownload;
private AudioSubModel aItem;
DownloadFileFromURL dwnldFileUrl;
public void setData(AudioSubModel item) {
aItem = item;
dwnldFileUrl = new DownloadFileFromURL();
if(item.isPlaying()){
ivPlay.setImageResource(R.drawable.pausebtn);
}else{
ivPlay.setImageResource(R.drawable.playbtn);
}
if(aItem.isDownloading()){
swtchDownload.setOnCheckedChangeListener(null);
swtchDownload.setChecked(true);
tvDownloadPercent.setText(aItem.getPercent() + "");
}else{
swtchDownload.setOnCheckedChangeListener(null);
swtchDownload.setChecked(false);
tvDownloadPercent.setText("0");
}
// holder.tvDownloadPercent.setText(data.get(position).getPercent()+" %");
tvDownload.setText(aItem.getDwnLbl());
tvTitle.setText(aItem.getTitle());
tvDesc.setText(aItem.getDesc());
Bitmap bmp = BitmapFactory.decodeFile(aItem.getImage());
ivImg.setImageBitmap(bmp);
// Log.e("MAIN", "IS DONE: " + aItem.isOn());
tvReadPdf.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
if(isPDFSupported(mContext)){
Uri path = Uri.fromFile(new File(aItem.getPdf()));
Intent objIntent = new Intent(Intent.ACTION_VIEW);
objIntent.setDataAndType(path, "application/pdf");
objIntent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
mContext.startActivity(objIntent);
}else{
if(GeneralClass.getConnectivityStatusString(mContext)){
Intent browserIntent = new Intent(Intent.ACTION_VIEW, Uri.parse("http://docs.google.com/gview?embedded=true&url="+aItem.getPdfurl()));
mContext.startActivity(browserIntent);
}else{
GeneralClass.showToast("Check internet connection to view pdf file", mContext);
}
}
}
});
ivPlay.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
if(aItem.isPlaying()){
aItem.setPlaying(false);
((MainActivity)mContext).stopAudioFile();
}else{
aItem.setPlaying(true);
((MainActivity)mContext).playAudioFile(aItem);
}
}
});
swtchDownload.setOnCheckedChangeListener(new OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton arg0, boolean arg1) {
// TODO Auto-generated method stub
// updateView(position, arg1);
Log.e("Audio ADAPTER", "file: " + arg1);
if(arg1){
aItem.setDownloading(true);
aItem.setDwnLbl("Downloading");
dwnldFileUrl.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR, aItem.getAudiourl());
}else if(!arg1){
aItem.setDownloading(false);
aItem.setDwnLbl("Download");
dwnldFileUrl.cancel(true);
}
}
});
ivCancel.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
aItem.setDownloading(false);
aItem.setDwnLbl("Download");
dwnldFileUrl.cancel(true);
// updateView(position, false);
// new DownloadFileFromURL(holder, position).execute(data.get(position).getAudiourl());
}
});
updateTimeRemaining();
}
public void updateTimeRemaining() {
// Log.e("MAIN", "GET TIME: " + aItem.getTimeStamp());
if(aItem.isDownloading()){
llDownload.setVisibility(View.VISIBLE);
tvDownloadPercent.setVisibility(View.VISIBLE);
tvDownloadPercent.setText(aItem.getPercent()+"");
// PBDownload.setProgress(aItem.getPercent());
tvDownload.setText(aItem.getDwnLbl());
}else{
llDownload.setVisibility(View.INVISIBLE);
tvDownloadPercent.setVisibility(View.INVISIBLE);
tvDownloadPercent.setText("0");
// PBDownload.setProgress(0);
tvDownload.setText(aItem.getDwnLbl());
}
// if(aItem.isOn()){
// tvTitle.setText(aItem.getPercent()+"");
// }else{
// tvTitle.setText("0");
// }
}
class DownloadFileFromURL extends AsyncTask<String, String, String> {
private volatile boolean running = true;
String finalFilePath="";
/**
* Before starting background thread
* Show Progress Bar Dialog
* */
@Override
protected void onPreExecute() {
super.onPreExecute();
}
/**
* Downloading file in background thread
* */
@Override
protected String doInBackground(String... f_url) {
int count;
try {
// URL url = new URL(f_url[0]);
URL url = new URL("http://www.robtowns.com/music/blind_willie.mp3");
URLConnection conection = url.openConnection();
conection.connect();
// getting file length
int lenghtOfFile = conection.getContentLength();
// input stream to read file - with 8k buffer
InputStream input = new BufferedInputStream(url.openStream(), 8192);
// Output stream to write file
String extStorageDirectory = Environment.getExternalStorageDirectory().toString();
String outputFile = extStorageDirectory+"/"+GeneralClass.FILE_PATH;
finalFilePath = outputFile+"/audio"+aItem.getId()+".mp3";
OutputStream output = new FileOutputStream(finalFilePath);
byte data[] = new byte[1024];
long total = 0;
while ((count = input.read(data)) != -1 && running) {
if(isCancelled()){
Log.e("ADAPTER", "Async break");
break;
}
total += count;
// publishing the progress....
// After this onProgressUpdate will be called
publishProgress(""+(int)((total*100)/lenghtOfFile));
// writing data to file
output.write(data, 0, count);
}
// flushing output
output.flush();
// closing streams
output.close();
input.close();
} catch (Exception e) {
Log.e("Error: ", e.getMessage());
}
return null;
}
@Override
protected void onCancelled() {
running = false;
Log.e("ADAPTER", "Async cancelled");
}
/**
* Updating progress bar
* */
@Override
protected void onProgressUpdate(String... progress) {
// setting progress percentage
aItem.setPercent(Integer.parseInt(progress[0]));
}
/**
* After completing background task
* Dismiss the progress dialog
* **/
@Override
protected void onPostExecute(String file_url) {
// dismiss the dialog after the file was downloaded
// dismissDialog(progress_bar_type);
Log.e("ADAPTER", "DONE ID: " + aItem.getId());
((MainActivity)mContext).updateAudioFileDownload(aItem.getId(), finalFilePath);
ivCancel.setVisibility(View.INVISIBLE);
}
}
}
public static boolean isPDFSupported(Context context) {
Intent i = new Intent( Intent.ACTION_VIEW );
final File tempFile = new File( context.getExternalFilesDir( Environment.DIRECTORY_DOWNLOADS ), "test.pdf" );
i.setDataAndType( Uri.fromFile( tempFile ), PDF_MIME_TYPE );
return context.getPackageManager().queryIntentActivities( i, PackageManager.MATCH_DEFAULT_ONLY ).size() > 0;
}
}
帮我解决这个重大问题。