iOS/Objective-C：EventKit中EKReminder与EKEvent对比及权限疑问

Hey there! Let's tackle your EventKit questions one by one—this is super common when getting started with the framework, so don't worry.

First, let's clear up the core distinctions between these two entities:

• Core Purpose: EKEvent is for time-bound activities (think meetings, birthdays, or doctor appointments) that have a defined start and end time. EKReminder is for task-based items (like "buy groceries" or "call mom") that don't necessarily need a fixed time slot, though you can add due dates if needed.
• Storage & Organization: Events live in EKCalendar containers, while reminders are stored in EKReminderList (even if some providers like iCloud link these, they're separate under the hood).
• Time & Priority: Events require startDate and endDate to exist. Reminders can have a dueDate, but they can also be completely time-free—plus they support a priority property to rank tasks.
• Alert Capabilities: Event alerts are time-based (e.g., "10 minutes before meeting start"). Reminders go further: you can set location-based alerts (like "remind me when I get home") and repeat alerts until the task is marked complete.
• Completion Tracking: Reminders have a completed flag and completionDate; once marked done, they'll disappear from active lists. Events don't have a "completion" state—they just show as past or future based on their time.

To answer your direct question: Yes, you must request access separately for EKEntityTypeEvent and EKEntityTypeReminder. Apple designed this separation for privacy reasons—users might want to let your app access their calendar events but not their personal reminders (or vice versa), so splitting permissions gives them more control.

That said, you can make the process feel less cumbersome with these tips:

• Request permissions only when needed: Don't ask for both permissions on app launch. Wait until the user interacts with a feature that requires one or the other—for example, ask for event access when they tap "View My Calendar" and reminder access when they tap "View My Tasks". Users are more likely to grant permissions when they understand why they're needed.
• Check existing status first: Before requesting access, use authorizationStatusForEntityType: to check if the user has already granted (or denied) permission. This avoids redundant prompts.
• Batch requests gracefully: If your app needs both permissions upfront, you can chain the requests in a single flow. For example, request event access first, then in its completion block, request reminder access. This way, the user gets two prompts back-to-back, but you're still following Apple's rules.

Here's a quick code snippet to handle permission checks and requests properly:

EKEventStore *eventStore = [[EKEventStore alloc] init];

// Check and request event access
EKAuthorizationStatus eventStatus = [EKEventStore authorizationStatusForEntityType:EKEntityTypeEvent];
if (eventStatus == EKAuthorizationStatusNotDetermined) {
    [eventStore requestAccessToEntityType:EKEntityTypeEvent completion:^(BOOL granted, NSError * _Nullable error) {
        if (granted) {
            // Handle event access granted
        } else {
            // Handle event access denied
        }
    }];
}

// Check and request reminder access
EKAuthorizationStatus reminderStatus = [EKEventStore authorizationStatusForEntityType:EKEntityTypeReminder];
if (reminderStatus == EKAuthorizationStatusNotDetermined) {
    [eventStore requestAccessToEntityType:EKEntityTypeReminder completion:^(BOOL granted, NSError * _Nullable error) {
        if (granted) {
            // Handle reminder access granted
        } else {
            // Handle reminder access denied
        }
    }];
}

内容的提问来源于stack exchange，提问作者user6631314