我正在开发一个用于从中下载文件的Android应用程序 服务器并将该文件保存到指定的路径..
我想在后台实现这一点,所以我在服务中编写下载功能。现在,当我在我的服务中使用代码时,我收到了错误。
任何人都可以帮我找到错误...谢谢..
我的服务代码是......
public class MyService extends Service {
Contacts c = new Contacts();
// File url to download
private static String file_url = "http://f23.wapka-files.com/download/6/9/4/1408248_69459e029be95f96ff9f98ff.mp3/a0f9f2173d3d81a49c28/01-Podimeesha-Anand.Madhusoodhanan.mp3y";
public MyService() {
}
@Override
public IBinder onBind(Intent intent) {
// TODO: Return the communication channel to the service.
throw new UnsupportedOperationException("Not yet implemented");
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
File folder = new File(Environment.getExternalStorageDirectory().getPath() + "/Jithin's/");
if (!folder.exists()) {
try {
folder.mkdirs();
} catch (Exception e) {
e.printStackTrace();
System.out.println("Default Save Path Creation Error:" + folder);
}
}
c.setA(Environment.getExternalStorageDirectory().toString() + "/Jithin's/downloadedfile.srt");
// starting new Async Task
new DownloadFileFromURL().execute(file_url);
MyService.this.stopService(intent);
return super.onStartCommand(intent, flags, startId);
}
/**
* Background Async Task to download file
* */
class DownloadFileFromURL extends AsyncTask<String, String, String> {
/**
* 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]);
URLConnection conection = url.openConnection();
// 6yi7 conection.connect();
conection.setRequestProperty("Accept-Encoding", "identity");
// 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
OutputStream output = new FileOutputStream(c.getA());
byte data[] = new byte[1024];
long total = 0;
while ((count = input.read(data)) != -1) {
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 onPostExecute(String file_url) {
Toast.makeText(MyService.this, "Downloaded Succesfully.. check Jithin's folder 2 see file...", Toast.LENGTH_LONG).show();
//my_image.setImageDrawable(Drawable.createFromPath(imagePath));
}
}
}
我的主要活动代码为..
public void download(View view) {
String value = getIntent().getExtras().getString("id");
if (value.equals("Song0")) {
Intent i=new Intent(Song_List.this, MyService.class);
startActivity(i);
Toast.makeText(Song_List.this, "Downloading..........", Toast.LENGTH_SHORT).show();
}
}
答案 0 :(得分:4)
更改您的代码,
Intent i=new Intent(Song_List.this, MyService.class);
startActivity(i);
这个,
Intent i=new Intent(Song_List.this, MyService.class);
startService(i);
答案 1 :(得分:2)
MyService是服务的延伸。所以你必须使用startService(Intent)。
因此您的代码可能如下所示:
public void download(View view) {
String value = getIntent().getExtras().getString("id");
if (value.equals("Song0")) {
Intent i=new Intent(Song_List.this, MyService.class);
startService(i);
Toast.makeText(Song_List.this, "Downloading..........", Toast.LENGTH_SHORT).show();
}
}
答案 2 :(得分:2)
首先,您应该使用 startActivity
启动此类服务public void download(View view) {
String value = getIntent().getExtras().getString("id");
if (value.equals("Song0")) {
Intent i=new Intent(Song_List.this, MyService.class);
startService(i);
Toast.makeText(Song_List.this, "Downloading..........", Toast.LENGTH_SHORT).show();
}
}
文件下载完成后停止服务后