Android：在 Asynctask 中发送通知 -> 崩溃

Question

我希望extends BroadcastReceiver 的班级首先使用 jsoup 阅读网站，然后（检查一些内容，然后）发送通知。 因为带有 jsoup 的部分需要AsyncTask，所以我猜通知代码需要在AsyncTask onPostExecute 部分中，但是应用程序在Alarm 或Calendar 代码给出的时间崩溃。

如果通知代码不在extends AsyncTask 的类中，则extends 和BroadcastReceiver 的类中的代码有效。

现在是 NotificationClass 的代码：

public class NotificationClass extends BroadcastReceiver{

Context specialContext;
int MID = 1;
long when = System.currentTimeMillis();
Uri alarmSound = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);

@Override
public void onReceive(Context context, Intent intent) {
    // TODO Auto-generated method stub

    new loadText().execute();
}
public class loadText extends AsyncTask<Void, Void, Void>
{
    String siteText;

    @Override
    protected Void doInBackground(Void... params) {

        Connection.Response res = null;
        try {
            res = Jsoup.connect("http://www.hpg-speyer.de/vertretungsplan/")  // Link der Hauptseite, wo auch der Login ist
                    .data("authid", "22101999AzaKur", "authpw", "451d28")  // Hier wären dann die Daten eingetragen
                    .method(Connection.Method.POST)
                    .execute();
        } catch (Exception e) {
            e.printStackTrace();
        }

        try {
            Document doc = res.parse();
        } catch (Exception e) {
            e.printStackTrace();
        }
        String sessionId = res.cookie("PHPSESSID");    // Name des Cookies


        Document doc2 = null;
        try {
            doc2 = Jsoup.connect("http://www.hpg-speyer.de/vertretungsplan/")  // das wäre der Link zu den Feldern
                    .cookie("PHPSESSID", sessionId)
                    .get();
            siteText = doc2.text();
        } catch (Exception e) {
            e.printStackTrace();
        }

        return null;
    }

    @Override
    protected void onPostExecute(Void aVoid) {
        super.onPostExecute(aVoid);

        NotificationManager notificationManager = (NotificationManager) specialContext
                .getSystemService(Context.NOTIFICATION_SERVICE);

        Intent notificationIntent = new Intent(specialContext, MainActivity.class);
        notificationIntent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);

        PendingIntent pendingIntent = PendingIntent.getActivity(specialContext, 0,
                notificationIntent, PendingIntent.FLAG_UPDATE_CURRENT);

        NotificationCompat.Builder mNotifyBuilder = (NotificationCompat.Builder) new NotificationCompat.Builder(
                specialContext).setSmallIcon(R.mipmap.ic_launcher)
                .setContentTitle("Alarm Fired")
                .setContentText("Events To be PErformed").setSound(alarmSound)
                .setAutoCancel(true).setWhen(when)
                .setContentIntent(pendingIntent)
                .setVibrate(new long[]{1000, 1000, 1000, 1000, 1000});

        if (siteText.contains("something")) {
            notificationManager.notify(MID, mNotifyBuilder.build());
            MID++;
        }
    }
}}

来自 logcat：

02-11 12:47:40.626 5413-5413/? I/art: Not late-enabling -Xcheck:jni (already on)
02-11 12:47:40.626 5413-5413/? W/art: Unexpected CPU variant for X86 using defaults: x86
02-11 12:47:40.708 5413-5413/de.kurt.vertretungsplan W/System: ClassLoader referenced unknown path: /data/app/de.kurt.vertretungsplan-1/lib/x86
02-11 12:47:40.711 5413-5413/de.kurt.vertretungsplan I/InstantRun: Instant Run Runtime started. Android package is de.kurt.vertretungsplan, real application class is null.
02-11 12:47:40.988 5413-5413/de.kurt.vertretungsplan W/System: ClassLoader referenced unknown path: /data/app/de.kurt.vertretungsplan-1/lib/x86
02-11 12:47:41.061 5413-5413/de.kurt.vertretungsplan W/art: Before Android 4.1, method android.graphics.PorterDuffColorFilter android.support.graphics.drawable.VectorDrawableCompat.updateTintFilter(android.graphics.PorterDuffColorFilter, android.content.res.ColorStateList, android.graphics.PorterDuff$Mode) would have incorrectly overridden the package-private method in android.graphics.drawable.Drawable
02-11 12:47:41.125 5413-5445/de.kurt.vertretungsplan D/NetworkSecurityConfig: No Network Security Config specified, using platform default
02-11 12:47:41.218 5413-5447/de.kurt.vertretungsplan I/OpenGLRenderer: Initialized EGL, version 1.4
02-11 12:47:41.218 5413-5447/de.kurt.vertretungsplan D/OpenGLRenderer: Swap behavior 1
02-11 12:47:41.248 5413-5447/de.kurt.vertretungsplan E/EGL_emulation: tid 5447: eglSurfaceAttrib(1174): error 0x3009 (EGL_BAD_MATCH)
02-11 12:47:41.248 5413-5447/de.kurt.vertretungsplan W/OpenGLRenderer: Failed to set EGL_SWAP_BEHAVIOR on surface 0x9c73fe80, error=EGL_BAD_MATCH

我是如何注意到崩溃的：

我将日历的时间放在相对较近的地方，然后运行应用程序并在它在虚拟设备上弹出并观察后将其关闭。 此方法在没有AsyncTask 的情况下有效，并且没有显示消息：“HPG Vertretungsplan 已停止”但有通知。

提前致谢。

Answer 1

您的 specialContext 尚未分配。在 onReceive 中将 specialContext 分配给传入的上下文

public void onReceive(Context context, Intent intent) {
// TODO Auto-generated method stub

specialContext=context;
new loadText().execute();}

Answer 2

SpecialContext 变量为空。试试这个

SpecialContext = getActivity();