状态栏中的通知，通知关闭时停止异步任务

Question

您好，我收到了从网络下载文件的通知。代码如下。我想处理通知上的点击操作，关闭它并停止 AsyncTask 作业。目前我的行为是不可理解的。就像，当我单击通知时，它关闭了它，但在调用 AsyncTask 的publishProgress 方法时再次打开。我如何处理点击通知？也许我可以采取与以前不同的方式？我将按钮放在 xml 布局 和 setOnClickListener 中以调用 cancel(boolean) 方法，但后来发现这是不可能的。

public class DownloadFileNotification extends AsyncTask<String, Integer, String> {

public DownloadVkVideoFiles(Context c, String title) {
  //constructor
}

public void createNotification() {
    //create notification
    notificationManager = (NotificationManager) context
            .getSystemService(context.NOTIFICATION_SERVICE);
    Intent notificationIntent = new Intent();

    PendingIntent pendingIntent = PendingIntent.getActivity(context, 0,
            notificationIntent, PendingIntent.FLAG_CANCEL_CURRENT);
    RemoteViews contentView = new RemoteViews(context.getPackageName(),
            R.layout.download_notification);

    // TODO change to shows title
    tickerText = context.getResources().getText(R.string.downloadTitle);
    icon = android.R.drawable.stat_sys_download;
    time = System.currentTimeMillis();

    notification = new Notification(icon, tickerText, time);
    notification.flags |= Notification.FLAG_ONGOING_EVENT;
    notification.flags |= Notification.FLAG_AUTO_CANCEL;

    contentView.setImageViewResource(R.id.downloadImage,
            R.drawable.download);
    contentView.setTextColor(R.id.title, notification_text_color);
    contentView.setFloat(R.id.title, "setTextSize",
            notification_text_size - 3);
    contentView.setTextViewText(R.id.title, title);
    contentView.setProgressBar(R.id.progressBar, 100, 0, false);

    notification.contentIntent = pendingIntent;
    notification.contentView = contentView;
    notificationManager.notify(HELLO_ID, notification);
}

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

@Override
protected String doInBackground(String... params) {
    //download file
}

@Override
public void onProgressUpdate(Integer... progress) {
    //update progress bar notification
}

@Override
protected void onPostExecute(String result) {
    super.onPostExecute(result);
  // result processing 
}

@Override
protected void onCancelled() {
    super.onCancelled();
}

}

Answer 1

我可以想象像广播接收器之类的东西，甚至可能是一个活动或服务，旨在接收通知点击触发的意图。该实体又可用于取消任务。

只需在正在运行的 Async 对象上调用 cancel(true) 方法即可。

//In your broadcast receiver/ activity / service
sometask.cancel(true);
.
.
.
//Inside doInBackground()
{
    while(!isCancled())
    {
        //continue task
    }
}

我希望它有帮助..