创建警报通知，只是想不出为什么我一直遇到错误的原因
android.database.CursorIndexOutOfBoundsException：已请求索引0，大小为0
失败（在计划课程alarm（）部分中。
alarmManager.set(AlarmManager.RTC_WAKEUP, time, PendingIntent.getBroadcast(context, nextAlarmId, intentAlarm, PendingIntent.FLAG_ONE_SHOT));
第一部分
private boolean createTestAlarm() {
long now = DateUtil.todayLong();
if (now <= DateUtil.getDateTimestamp(course.start)) {
AlarmHandler.scheduleCourseAlarm(getApplicationContext(), courseId, DateUtil.getDateTimestamp(course.start),
"Course starts today!", course.name + " begins on " + course.start);
}
第二部分
public class AlarmHandler extends BroadcastReceiver {
public static final String courseAlarmFile = "courseAlarms";
public static final String assessmentAlarmFile = "assessmentAlarms";
public static final String alarmFile = "alarmFile";
public static final String nextAlarmField = "nextAlarmId";
@Override
public void onReceive(Context context, Intent intent) {
String destination = intent.getStringExtra("destination");
if (destination == null || destination.isEmpty()) {
destination = "";
}
int id = intent.getIntExtra("id", 0);
String alarmTitle = intent.getStringExtra("title");
String alarmText = intent.getStringExtra("text");
int nextAlarmId = intent.getIntExtra("nextAlarmId", getAndIncrementNextAlarmId(context));
NotificationCompat.Builder builder = new NotificationCompat.Builder(context)
.setSmallIcon(R.drawable.ic_calendar_clock)
.setContentTitle(alarmTitle)
.setContentText(alarmText);
Intent resultIntent;
Uri uri;
SharedPreferences sharedPreferences;
switch (destination) {
case "course":
Course course = DatabaseControl.getCourse(context, id);
if (course != null && course.notifications == 1) {
resultIntent = new Intent(context, CourseViewerActivity.class);
uri = Uri.parse(DatabaseData.COURSES_URI + "/" + id);
resultIntent.putExtra(DatabaseData.COURSE_CONTENT_TYPE, uri);
}
else {
return;
}
break;
case "assessment":
Assessment assessment = DatabaseControl.getAssessment(context, id);
if (assessment != null && assessment.notifications == 1) {
resultIntent = new Intent(context, AssessmentViewerActivity.class);
uri = Uri.parse(DatabaseData.ASSESSMENTS_URI + "/" + id);
resultIntent.putExtra(DatabaseData.ASSESSMENT_CONTENT_TYPE, uri);
}
else {
return;
}
break;
default:
resultIntent = new Intent(context, MainActivity.class);
break;
}
TaskStackBuilder stackBuilder = TaskStackBuilder.create(context);
stackBuilder.addParentStack(MainActivity.class);
stackBuilder.addNextIntent(resultIntent);
PendingIntent resultPendingIntent = stackBuilder.getPendingIntent(0, PendingIntent.FLAG_UPDATE_CURRENT);
builder.setContentIntent(resultPendingIntent).setAutoCancel(true);
NotificationManager notificationManager = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);
notificationManager.notify(nextAlarmId, builder.build());
}
public static boolean scheduleCourseAlarm(Context context, long id, long time, String title, String text) {
AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
int nextAlarmId = getNextAlarmId(context);
Intent intentAlarm = new Intent(context, AlarmHandler.class);
intentAlarm.putExtra("id", id);
intentAlarm.putExtra("title", title);
intentAlarm.putExtra("text", text);
intentAlarm.putExtra("destination", "course");
intentAlarm.putExtra("nextAlarmId", nextAlarmId);
alarmManager.set(AlarmManager.RTC_WAKEUP, time, PendingIntent.getBroadcast(context, nextAlarmId, intentAlarm, PendingIntent.FLAG_ONE_SHOT));
SharedPreferences sp = context.getSharedPreferences(courseAlarmFile, Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sp.edit();
editor.putInt(Long.toString(id), nextAlarmId);
editor.commit();
incrementNextAlarmId(context);
return true;
}
private static int getNextAlarmId(Context context) {
SharedPreferences alarmPrefs;
alarmPrefs = context.getSharedPreferences(alarmFile, Context.MODE_PRIVATE);
int nextAlarmId = alarmPrefs.getInt(nextAlarmField, 1);
return nextAlarmId;
}
private static void incrementNextAlarmId(Context context) {
SharedPreferences alarmPrefs;
alarmPrefs = context.getSharedPreferences(alarmFile, Context.MODE_PRIVATE);
int nextAlarmId = alarmPrefs.getInt(nextAlarmField, 1);
SharedPreferences.Editor alarmEditor = alarmPrefs.edit();
alarmEditor.putInt(nextAlarmField, nextAlarmId + 1);
alarmEditor.commit();
}
private static int getAndIncrementNextAlarmId(Context context) {
int nextAlarmId = getNextAlarmId(context);
incrementNextAlarmId(context);
return nextAlarmId;
}
}
第3部分-数据库代码
public static Course getCourse(Context context, long courseId) {
Cursor cursor = context.getContentResolver().query(DatabaseData.COURSES_URI, Database.COURSES_COLUMNS,
Database.COURSES_TABLE_ID + " = " + courseId, null, null);
cursor.moveToFirst();
Long termId = cursor.getLong(cursor.getColumnIndex(Database.COURSE_TERM_ID));
String courseName = cursor.getString(cursor.getColumnIndex(Database.COURSE_NAME));
String courseDescription = cursor.getString(cursor.getColumnIndex(Database.COURSE_DESCRIPTION));
String courseStart = cursor.getString(cursor.getColumnIndex(Database.COURSE_START));
String courseEnd = cursor.getString(cursor.getColumnIndex(Database.COURSE_END));
String courseMentor = cursor.getString(cursor.getColumnIndex(Database.COURSE_MENTOR));
String courseMentorPhone = cursor.getString(cursor.getColumnIndex(Database.COURSE_MENTOR_PHONE));
String courseMentorEmail = cursor.getString(cursor.getColumnIndex(Database.COURSE_MENTOR_EMAIL));
String courseNote = cursor.getString(cursor.getColumnIndex(Database.COURSE_NOTE));
int courseNotifications = (cursor.getInt(cursor.getColumnIndex(Database.COURSE_NOTIFICATIONS)));
Course c = new Course();
c.courseId = courseId;
c.termId = termId;
c.name = courseName;
c.description = courseDescription;
c.start = courseStart;
c.end = courseEnd;
c.mentor = courseMentor;
c.mentorPhone = courseMentorPhone;
c.mentorEmail = courseMentorEmail;
c.note = courseNote;
c.notifications = courseNotifications;
return c;
}