Question

我正在做计时器应用，但我不明白程序错误的原因。这是我的代码

public class SampleBootReceiver extends BroadcastReceiver {
    private PendingIntent pendingIntent;
    AlarmManager alarmManager;
    @Override

    public void onReceive(Context context, Intent intent) {

        DatabaseHandler db ;
        db=new DatabaseHandler(context);
    Contact cn=    db.getContact(1);

        Calendar calendar = Calendar.getInstance();
        calendar.set(Calendar.HOUR_OF_DAY, Integer.parseInt(cn.getHour()));
        calendar.set(Calendar.MINUTE, Integer.parseInt(cn.getMinutes()));
        calendar.set(Calendar.DATE, Integer.parseInt(cn.getDay()));
        Intent myIntent = new Intent(context,AlarmReceiver.class);
        Log.w("log", "HOURS" +Integer.parseInt(cn.getHour()));
        Log.w("log", "MINUTE" +Integer.parseInt(cn.getMinutes()));
        Log.w("log", "DAY" +Integer.parseInt(cn.getDay()));
        Log.w("log", "id" + cn.getId());
        Log.w("log", "phone" + cn.getPhoneNumber());
        Log.w("log", "sms" + cn.getSmsBody());

        pendingIntent = PendingIntent.getBroadcast(context, 0, myIntent, pendingIntent.FLAG_UPDATE_CURRENT);
        alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), 20000, pendingIntent);

    }
}

这是alarmManager的行alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, calendar.getTimeInMillis(), 20000, pendingIntent);

中的错误NullPointerException

Answer 1

到目前为止，我在您的代码中看到，您从未初始化alarmManager，因此当您致电setRepeating时它为空。

在调用此方法之前，您应该有类似这样的内容

alarmManager = (AlarmManager)context.getSystemService(Context.ALARM_SERVICE);

警报管理器错误NullPointerException

1 个答案: