今月のすべてのレコードを取得したいので、月の初日と月末の 2 つの述語をスタックします。CoreData を使用しているため、日付は実際には NSTimeInterval として保存されます。
NSCalendar *calendar = [NSCalendar currentCalendar];
//Get beginning of current month
NSDateComponents *beginningOfCurrentMonthComponents = [calendar components:(NSEraCalendarUnit | NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit) fromDate:date];
[beginningOfCurrentMonthComponents setDay:1];
NSDate *beginningOfCurrentMonthDate = [calendar dateFromComponents:beginningOfCurrentMonthComponents];
//Set a single month to be added to the current month
NSDateComponents *oneMonth = [[NSDateComponents alloc] init];
[oneMonth setMonth:1];
//determine the last day of this month
NSDate *beginningOfNextMonthDate = [calendar dateByAddingComponents:oneMonth toDate:beginningOfCurrentMonthDate options:0];
NSMutableArray *parr = [NSMutableArray array];
[parr addObject:[NSPredicate predicateWithFormat:@"recordDate >= %d", [beginningOfCurrentMonthDate timeIntervalSince1970]]];
[parr addObject:[NSPredicate predicateWithFormat:@"recordDate < %d", [beginningOfNextMonthDate timeIntervalSince1970]]];
//Give me everything from beginning of this month until end of this month
NSPredicate *predicate = [NSCompoundPredicate andPredicateWithSubpredicates:parr];
return [allRecords filteredArrayUsingPredicate:predicate];
フィルター処理された配列を返すと、次のエラー メッセージでクラッシュします。
2013-10-25 19:09:39.702 [3556:a0b] -[__NSCFNumber timeIntervalSinceReferenceDate]: unrecognized selector sent to instance 0x8911440
2013-10-25 19:09:39.704 [3556:a0b] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFNumber timeIntervalSinceReferenceDate]: unrecognized selector sent to instance 0x8911440'
*** First throw call stack:
(
0 CoreFoundation 0x01aa85e4 __exceptionPreprocess + 180
1 libobjc.A.dylib 0x0182b8b6 objc_exception_throw + 44
2 CoreFoundation 0x01b45903 -[NSObject(NSObject) doesNotRecognizeSelector:] + 275
3 CoreFoundation 0x01a9890b ___forwarding___ + 1019
4 CoreFoundation 0x01a984ee _CF_forwarding_prep_0 + 14
5 CoreFoundation 0x01a7e3e3 -[NSDate compare:] + 67
6 Foundation 0x014194fe -[NSComparisonPredicateOperator performPrimitiveOperationUsingObject:andObject:] + 408
7 Foundation 0x014b03de -[NSPredicateOperator performOperationUsingObject:andObject:] + 306
8 Foundation 0x014b016c -[NSComparisonPredicate evaluateWithObject:substitutionVariables:] + 347
9 Foundation 0x014299b6 -[NSCompoundPredicateOperator evaluatePredicates:withObject:substitutionVariables:] + 240
10 Foundation 0x01429845 -[NSCompoundPredicate evaluateWithObject:substitutionVariables:] + 294
11 Foundation 0x014b0009 -[NSPredicate evaluateWithObject:] + 48
12 Foundation 0x014aff89 _filterObjectsUsingPredicate + 418
13 Foundation 0x014afd42 -[NSArray(NSPredicateSupport) filteredArrayUsingPredicate:] + 328
また、このループを使用して、recordDate が実際に配列内に存在することを示しました。
for (FTRecord *r in allRecords) {
NSLog(@"%f", [r recordDate]);
}
2013-10-25 19:09:35.860 [3556:a0b] 1380582000.000000
2013-10-25 19:09:36.556 [3556:a0b] 1380754800.000000