Android-下载文件+;状态栏通知使手机变慢

Android-下载文件+;状态栏通知使手机变慢,android,notifications,download,android-asynctask,slowdown,Android,Notifications,Download,Android Asynctask,Slowdown,我目前有一个asynctask,可以从服务器下载mp3。当用户开始下载时,将创建一个状态栏通知。这将实时显示下载进度。我唯一担心的是手机的速度太慢了。是否有任何方法可以延迟显示的进度或使代码更快?谢谢 代码如下: public class DownloadFile extends AsyncTask<String, String, String> { CharSequence contentText; Context context; CharSequence

我目前有一个
asynctask
,可以从服务器下载mp3。当用户开始下载时,将创建一个状态栏通知。这将实时显示下载进度。我唯一担心的是手机的速度太慢了。是否有任何方法可以延迟显示的进度或使代码更快?谢谢

代码如下:

public class DownloadFile extends AsyncTask<String, String, String> {
    CharSequence contentText;
    Context context;
    CharSequence contentTitle;
    PendingIntent contentIntent;
    int HELLO_ID = 1;
    long time;
    int icon;
    CharSequence tickerText;
    File file;

    public void downloadNotification() {
        String ns = Context.NOTIFICATION_SERVICE;
        notificationManager = (NotificationManager) getSystemService(ns);

        icon = R.drawable.sdricontest;
        //the text that appears first on the status bar
        tickerText = "Downloading...";
        time = System.currentTimeMillis();

        notification = new Notification(icon, tickerText, time);

        context = getApplicationContext();
        //the bold font
        contentTitle = "Your download is in progress";
        //the text that needs to change
        contentText = "0% complete";
        Intent notificationIntent = new Intent(Intent.ACTION_VIEW);
        notificationIntent.setType("audio/*");
        contentIntent = PendingIntent.getActivity(context, 0, notificationIntent, 0);

        notification.setLatestEventInfo(context, contentTitle, contentText, contentIntent);
        notificationManager.notify(HELLO_ID, notification);
    }

    @Override
    protected void onPreExecute() {
        //execute the status bar notification
        downloadNotification();
        super.onPreExecute();
    }

    @Override
    protected String doInBackground(String... url) {
        int count;
        try {
            URL url2 = new URL(sdrUrl);
            HttpURLConnection connection = (HttpURLConnection) url2.openConnection();
            connection.setRequestMethod("GET");
            connection.setDoOutput(true);
            connection.connect();

            int lengthOfFile = connection.getContentLength();

            //make the stop drop rave folder
            File sdrFolder = new File(Environment.getExternalStorageDirectory() + "/StopDropRave");
            boolean success = false;

            if (!sdrFolder.exists()) {
                success = sdrFolder.mkdir();
            }
            if (!success) {
                String PATH = Environment.getExternalStorageDirectory()
                        + "/StopDropRave/";
                file = new File(PATH);
                file.mkdirs();
            } else {
                String PATH = Environment.getExternalStorageDirectory()
                        + "/StopDropRave/";
                file = new File(PATH);
                file.mkdirs();
            }

            String[] path = url2.getPath().split("/");
            String mp3 = path[path.length - 1];
            String mp31 = mp3.replace("%20", " ");
            String sdrMp3 = mp31.replace("%28", "(");
            String sdrMp31 = sdrMp3.replace("%29", ")");
            String sdrMp32 = sdrMp31.replace("%27", "'");

            File outputFile = new File(file, sdrMp32);
            FileOutputStream fos = new FileOutputStream(outputFile);

            InputStream input = connection.getInputStream();

            byte[] data = new byte[1024];
            long total = 0;
            while ((count = input.read(data)) != -1) {
                total += count;
                publishProgress("" + (int) (total * 100 / lengthOfFile));
                fos.write(data, 0, count);
            }
            fos.close();
            input.close();
        } catch (IllegalArgumentException e) {
            e.printStackTrace();
        } catch (IllegalStateException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return null;
    }

    @Override
    public void onProgressUpdate(String... progress) {
        contentText = Integer.parseInt(progress[0]) + "% complete";
        notification.setLatestEventInfo(context, contentTitle, contentText, contentIntent);
        notificationManager.notify(HELLO_ID, notification);
        super.onProgressUpdate(progress);
    }
}
公共类下载文件扩展异步任务{
字符序列内容文本;
语境;
字符序列内容标题;
悬而未决的意图;
int HELLO_ID=1;
长时间;
int图标;
字符序列tickerText;
文件;
公共无效下载通知(){
字符串ns=Context.NOTIFICATION\u服务;
notificationManager=(notificationManager)getSystemService(ns);
icon=R.drawable.sdricontest;
//首先出现在状态栏上的文本
tickerText=“正在下载…”;
时间=System.currentTimeMillis();
通知=新通知(图标、tickerText、时间);
context=getApplicationContext();
//粗体字
contentTitle=“您的下载正在进行”;
//需要更改的文本
contentText=“0%完成”;
Intent notificationIntent=新意图(Intent.ACTION\u视图);
notificationIntent.setType(“音频/*”);
contentIntent=PendingEvent.getActivity(上下文,0,notificationIntent,0);
setLateStevenInfo(上下文、contentTitle、contentText、contentIntent);
notificationManager.notify(HELLO_ID,notification);
}
@凌驾
受保护的void onPreExecute(){
//执行状态栏通知
下载通知();
super.onPreExecute();
}
@凌驾
受保护的字符串doInBackground(字符串…url){
整数计数;
试一试{
URL url2=新URL(SDURL);
HttpURLConnection connection=(HttpURLConnection)url2.openConnection();
connection.setRequestMethod(“GET”);
connection.setDoOutput(真);
connection.connect();
int lengthOfFile=connection.getContentLength();
//使停止放置rave文件夹
File sdrFolder=新文件(Environment.getExternalStorageDirectory()+“/StopDropRave”);
布尔成功=假;
如果(!sdrFolder.exists()){
success=sdrFolder.mkdir();
}
如果(!成功){
String PATH=Environment.getExternalStorageDirectory()
+“/StopDropRave/”;
文件=新文件(路径);
mkdirs()文件;
}否则{
String PATH=Environment.getExternalStorageDirectory()
+“/StopDropRave/”;
文件=新文件(路径);
mkdirs()文件;
}
字符串[]path=url2.getPath().split(“/”);
字符串mp3=path[path.length-1];
字符串mp31=mp3.replace(“%20”和“”);
字符串sdrm3=mp31。替换(“%28”和“(”);
字符串sdrMp31=sdrm3.replace(“%29”,”);
字符串sdrMp32=sdrMp31.replace(“%27”和“”);
File outputFile=新文件(文件,sdrMp32);
FileOutputStream fos=新的FileOutputStream(outputFile);
InputStream输入=连接。getInputStream();
字节[]数据=新字节[1024];
长总计=0;
而((计数=输入。读取(数据))!=-1){
总数+=计数;
出版进度(“+(int)(总计*100/长办公室));
fos.写入(数据,0,计数);
}
fos.close();
input.close();
}捕获(IllegalArgumentException e){
e、 printStackTrace();
}捕获(非法状态){
e、 printStackTrace();
}捕获(IOE异常){
e、 printStackTrace();
}
返回null;
}
@凌驾
public void onProgressUpdate(字符串…进度){
contentText=Integer.parseInt(进度[0])+%complete;
setLateStevenInfo(上下文、contentTitle、contentText、contentIntent);
notificationManager.notify(HELLO_ID,notification);
super.onProgressUpdate(进度);
}
}

我看到了类似的结果,你不需要经常推送更新通知,我将我的更新更改为每秒只更新几次。(例如,在onProgressUpdate中,记录您上次调用notify的时间,并且仅当您上次调用的时间超过100毫秒,或者处于最大值时才调用notify。

我遇到了同样的问题,即即使间隔3秒也无法更新进度条通知,因此经过数小时的挖掘后,我意识到H无论何时更新通知,都必须重新实例化RemoteView对象,并将其初始化为通知对象的contentView。完成此操作后,我能够以100ms-500ms的间隔更新通知进度条,并且在很长的一段时间内不会遇到任何UI阻塞

注意:如果您不同意,您可以在注释标记行后运行此代码段来验证此答案,并查看差异。可能需要大约5分钟才能启动严重的UI阻塞,这将使设备发热并可能停止运行。 我尝试使用Android 4.2.2的S3 mini,updateNotification(..)方法是从服务内的工作线程调用的。而且我已经对它进行了双重检查,不知道在使用Notification.Builder时会发生什么情况。

注:在3年的问题之后写下这个答案的原因是因为我想知道,我甚至没有找到一个stackoverflow的答案或其他博客帖子,用这个非常简单的解决方案来处理这个严重的问题

我希望
//long mMaxtTimeoutNanos = 1000000000 // 1000ms.
long mMinTimeNanos     = 100000000;//100ms minimum update limit. For fast downloads.
long mMaxtTimeoutNanos = 500000000;//500ms maximum update limit. For Slow downloads
long mLastTimeNanos = 0;
private void updateNotification(.....){
    // Max Limit
    if (mUpdateNotification || ((System.nanoTime()-mLastTimeNanos) > mMaxtTimeoutNanos)) {
        // Min Limit
        if (((System.nanoTime() - mLastTimeNanos) > mMinTimeNanos)) {
            mLastTimeNanos = System.nanoTime();
            // instantiate new RemoteViews object.
            // (comment out this line and instantiate somewhere
            // to verify that the above told answer is true)
            mRemoteView = new RemoteViews(getPackageName(),
                    R.layout.downloader_notification_layout);
            // Upate mRemoteView with changed data
            ...
            ...
            // Initialize the already existing Notification contentView
            // object with newly instatiated mRemoteView.
            mNotification.contentView = mRemoteView;
            mNotificationManager.notify(mNotificatoinId, mNotification);
            mUpdateNotification = false;
        }
    }
}
class DownloadMaterial extends AsyncTask<String, String, String> {

    CountDownTimer cdt;
    int id = i;
    NotificationManager mNotifyManager;
    NotificationCompat.Builder mBuilder;

    @Override
    protected void onPreExecute() {
        /**
         * Create custom Count Down Timer
         */
        cdt = new CountDownTimer(100 * 60 * 1000, 500) {
            public void onTick(long millisUntilFinished) {
                mNotifyManager.notify(id, mBuilder.build());
            }

            public void onFinish() {
                mNotifyManager.notify(id, mBuilder.build());
            }
        };
    }

    @Override
    protected String doInBackground(String... strings) {
        /**
         * Start timer to update Notification
         * Set Progress to 20 after connection
         * Build Notification
         * Increment Progress
         * Download and Save file
         */
        try {
            mNotifyManager =
                    (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);
            mBuilder = new NotificationCompat.Builder(context);
            mBuilder.setContentTitle("Downloading File")
                    .setContentText(file_name)
                    .setProgress(0, 100, false)
                    .setOngoing(true)
                    .setSmallIcon(R.mipmap.ic_launcher)
                    .setPriority(Notification.PRIORITY_LOW);

            // Initialize Objects here
            publishProgress("5");
            mNotifyManager.notify(id, mBuilder.build());
            cdt.start();

            // Create connection here
            publishProgress("20");

            // Download file here
            while ((count = input.read(data)) != -1) {
                total += count;
                publishProgress("" + (int) (20 + (total * 80 / fileLength)));
                output.write(data, 0, count);
            }
        } catch (Exception e) {
            return "Failed";
        }
        return "Success";
    }

    @Override
    protected void onProgressUpdate(String... values) {
        /**
         * Update Download Progress
         */
        mBuilder.setContentInfo(values[0] + "%")
                .setProgress(100, Integer.parseInt(values[0]), false);
    }

    @Override
    protected void onPostExecute(String s) {

        String title;
        if (s.equals("Success")) {
            title = "Downloaded";
        } else {
            title = "Error Occurred";
        }
        mBuilder.setContentTitle(title)
                .setContentInfo("")
                .setOngoing(false)
                .setProgress(0, 0, false);
        cdt.onFinish();
        cdt.cancel();
    }
}
        // While loop from generic download method.
        int previousProgress = 0;
        while ((count = inputStream.read(buff)) != -1) {
            outputStream.write(buff, 0, count);
            totalBytesDownloaded += count;
            int prog = (int) (totalBytesDownloaded * 100 / contentLength);
            if (prog > previousProgress) {
                // Only post progress event if we've made progress.
                previousProgress = prog;
                myPostProgressMethod(prog);

            }
        }