日曆商店：如何區分事件日曆和任務日曆？

Question

我正在開發具有提醒組件的應用程序。我使用Calendar Store來獲取日曆列表，並且我希望用戶選擇他們想要添加任務的日曆。問題是，CalCalendar似乎沒有區分事件日曆和任務日曆。

NSArray* calendars = [[CalCalendarStore defaultCalendarStore] calendars]; 
for(CalCalendar* aCalendar in calendars) { 
    if(aCalendar.isEditable) { 
     NSLog(@"editable calendar: %@", aCalendar); 
    } 
} 

此輸出：

editable calendar: CalCalendar <0x6e04d10> {UID = 8AA8FFAD-D781-47F7-9231-CF66E1753983; title = Work; notes = (null); color = NSCalibratedRGBColorSpace 0.054902 0.380392 0.72549 1; type = CalDAV; editable = 1} 
editable calendar: CalCalendar <0x6e05000> {UID = A7F4A1B2-D1CF-4A20-9F84-CD1A1E99773E; title = Home; notes = ; color = NSCalibratedRGBColorSpace 0.72549 0.054902 0.156863 1; type = CalDAV; editable = 1} 
editable calendar: CalCalendar <0x6e050f0> {UID = 43B14D2A-9976-461C-8EFE-5FA029381828; title = Personal; notes = (null); color = NSCalibratedRGBColorSpace 0.901961 0.784314 0 1; type = CalDAV; editable = 1} 
editable calendar: CalCalendar <0x6e05140> {UID = F42EC365-20AC-4251-B45E-FB7F169928F0; title = Mac; notes = (null); color = NSCalibratedRGBColorSpace 0.054902 0.380392 0.72549 1; type = Local; editable = 1} 
editable calendar: CalCalendar <0x6e05190> {UID = FF771FF9-3969-4001-BBA4-9B7B00E80291; title = Cloud 2; notes = (null); color = NSCalibratedRGBColorSpace 0.054902 0.380392 0.72549 1; type = CalDAV; editable = 1} 
editable calendar: CalCalendar <0x6e051e0> {UID = 40234537-869C-4CC2-89B9-DD4F7D36C169; title = Groceries; notes = ; color = NSCalibratedRGBColorSpace 0.443137 0.101961 0.462745 1; type = CalDAV; editable = 1} 

我知道第2事件日曆，最後4是任務列表。而且，iCal明確知道其中的差異，因爲它只顯示事件的事件日曆和任務的任務日曆。

但似乎沒有辦法通過Calendar Store API來以編程方式確定這一點，除非我錯過了一些東西。

更新：我看到我不是唯一注意到這一點的人，因爲我發現了rdar://10377730。我剛剛提交了自己的報告，作爲rdar://10980542

Answer 1

我對它並不滿意，但我現在使用的解決方法是簡單地嘗試在每個日曆中創建一個任務。如果您嘗試在事件日曆中創建任務，則會出現錯誤。它看起來有點像：

- (BOOL) isCalendarAUsableTaskList:(CalCalendar*)aCalendar 
{ 
    if(!aCalendar.isEditable) return NO; 

    // Try to make a task here. 
    CalTask* newTask = [CalTask task]; 
    newTask.calendar = aCalendar; 
    newTask.title = @"Test Item"; 
    NSError* anError = nil; 
    if(![[CalCalendarStore defaultCalendarStore] saveTask:newTask error:&anError]) { 
     // Couldn't make a task, this calendar is no bueno. 
     NSLog(@"Error saving task to calendar %@ (%@)", aCalendar.title, [anError localizedDescription]); 
     return NO; 
    } 

    // Created a task. Now clean up on our way out. 
    NSLog(@"Saved task to calendar %@", aCalendar.title); 
    [[CalCalendarStore defaultCalendarStore] removeTask:newTask error:nil]; 

    return YES; 
}