NSPredicate: filtrar objetos por día de la propiedad NSDate

Ejemplo sobre cómo configurar también startDate y endDate a la respuesta dada anteriormente:

...

NSCalendar *calendar = [NSCalendar currentCalendar];
NSDateComponents *components = [calendar components:(NSYearCalendarUnit | NSMonthCalendarUnit ) fromDate:[NSDate date]];
//create a date with these components
NSDate *startDate = [calendar dateFromComponents:components];
[components setMonth:1];
[components setDay:0]; //reset the other components
[components setYear:0]; //reset the other components
NSDate *endDate = [calendar dateByAddingComponents:components toDate:startDate options:0];
predicate = [NSPredicate predicateWithFormat:@"((date >= %@) AND (date < %@)) || (date = nil)",startDate,endDate];

...

Aquí estaba buscando todas las entradas dentro de un mes. Vale la pena mencionar, que este ejemplo también muestra cómo buscar ' nil ' date-entires.

En Swift tengo algo similar a:

        let dateFormatter = NSDateFormatter()
        dateFormatter.dateFormat = "yyyy-MM-dd"
        let date = dateFormatter.dateFromString(predicate)
        let calendar = NSCalendar(calendarIdentifier: NSGregorianCalendar)
        let components = calendar!.components(
            NSCalendarUnit.CalendarUnitYear |
                NSCalendarUnit.CalendarUnitMonth |
                NSCalendarUnit.CalendarUnitDay |
                NSCalendarUnit.CalendarUnitHour |
                NSCalendarUnit.CalendarUnitMinute |
                NSCalendarUnit.CalendarUnitSecond, fromDate: date!)
        components.hour = 00
        components.minute = 00
        components.second = 00
        let startDate = calendar!.dateFromComponents(components)
        components.hour = 23
        components.minute = 59
        components.second = 59
        let endDate = calendar!.dateFromComponents(components)
        predicate = NSPredicate(format: "day >= %@ AND day =< %@", argumentArray: [startDate!, endDate!])

Tuve dificultades para descubrir que la interpolación de cadenas "\(this notation)" no funciona para comparar fechas en NSPredicate.

Porté la respuesta de Glauco Neves a Swift 2.0 y la envolví dentro de una función que recibe una fecha y devuelve el NSPredicate para el día correspondiente:

func predicateForDayFromDate(date: NSDate) -> NSPredicate {
    let calendar = NSCalendar(calendarIdentifier: NSCalendarIdentifierGregorian)
    let components = calendar!.components([.Year, .Month, .Day, .Hour, .Minute, .Second], fromDate: date)
    components.hour = 00
    components.minute = 00
    components.second = 00
    let startDate = calendar!.dateFromComponents(components)
    components.hour = 23
    components.minute = 59
    components.second = 59
    let endDate = calendar!.dateFromComponents(components)

    return NSPredicate(format: "day >= %@ AND day =< %@", argumentArray: [startDate!, endDate!])
}

Extensión Swift 3.0 para la fecha:

extension Date{

func makeDayPredicate() -> NSPredicate {
    let calendar = Calendar.current
    var components = calendar.dateComponents([.year, .month, .day, .hour, .minute, .second], from: self)
    components.hour = 00
    components.minute = 00
    components.second = 00
    let startDate = calendar.date(from: components)
    components.hour = 23
    components.minute = 59
    components.second = 59
    let endDate = calendar.date(from: components)
    return NSPredicate(format: "day >= %@ AND day =< %@", argumentArray: [startDate!, endDate!])
}
}

Luego use como:

 let fetchReq = NSFetchRequest(entityName: "MyObject")
 fetchReq.predicate = myDate.makeDayPredicate()

Añadiendo a la respuesta de Rafael (increíblemente útil, gracias!), porting for Swift 3.

func predicateForDayFromDate(date: Date) -> NSPredicate {
    let calendar = Calendar(identifier: Calendar.Identifier.gregorian)
    var components = calendar.dateComponents([.year, .month, .day, .hour, .minute, .second], from: date)
    components.hour = 00
    components.minute = 00
    components.second = 00
    let startDate = calendar.date(from: components)
    components.hour = 23
    components.minute = 59
    components.second = 59
    let endDate = calendar.date(from: components)

    return NSPredicate(format: "YOUR_DATE_FIELD >= %@ AND YOUR_DATE_FIELD =< %@", argumentArray: [startDate!, endDate!])
}

Recientemente he pasado algún tiempo tratando de resolver este mismo problema y agregar lo siguiente a la lista de alternativas para preparar las fechas de inicio y finalización (incluye el método actualizado para iOS 8 y superiores)...

NSDate *dateDay = nil;
NSDate *dateDayStart = nil;
NSDate *dateDayNext = nil;

dateDay = <<USER_INPUT>>;

dateDayStart = [[NSCalendar currentCalendar] startOfDayForDate:dateDay];

//  dateDayNext EITHER
dateDayNext = [dateDayStart dateByAddingTimeInterval:(24 * 60 * 60)];

//  dateDayNext OR
NSDateComponents *dateComponentDay = nil;
dateComponentDay = [[NSDateComponents alloc] init];
[dateComponentDay setDay:1];
dateDayNext = [[NSCalendar currentCalendar] dateByAddingComponents:dateComponentDay
                                                            toDate:dateDayStart
                                                           options:NSCalendarMatchNextTime];

...y el NSPredicate para los Datos Básicos NSFetchRequest (como ya se muestra arriba en otras respuestas)...

[NSPredicate predicateWithFormat:@"(dateAttribute >= %@) AND (dateAttribute < %@)", dateDayStart, dateDayNext]]

Para mí esto funciona.

NSCalendar *calendar = [NSCalendar currentCalendar];
    NSDateComponents *components = [calendar components:(NSYearCalendarUnit | NSMonthCalendarUnit ) fromDate:[NSDate date]];
    //create a date with these components
    NSDate *startDate = [calendar dateFromComponents:components];
    [components setMonth:0];
    [components setDay:0]; //reset the other components
    [components setYear:0]; //reset the other components
    NSDate *endDate = [calendar dateByAddingComponents:components toDate:startDate options:0];

    startDate = [NSDate date];
    endDate = [startDate dateByAddingTimeInterval:-(7 * 24 * 60 * 60)];//change here

    NSString *startTimeStamp = [[NSNumber numberWithInt:floor([endDate timeIntervalSince1970])] stringValue];
    NSString *endTimeStamp = [[NSNumber numberWithInt:floor([startDate timeIntervalSince1970])] stringValue];


   NSPredicate *predicate = [NSPredicate predicateWithFormat:@"((paidDate1 >= %@) AND (paidDate1 < %@))",startTimeStamp,endTimeStamp];
    NSLog(@"predicate is %@",predicate);
    totalArr = [completeArray filteredArrayUsingPredicate:predicate];
    [self filterAndPopulateDataBasedonIndex];
    [self.tableviewObj reloadData];
    NSLog(@"result is %@",totalArr);

He filtrado la matriz desde la fecha actual hasta 7 días atrás. Quiero decir que estoy recibiendo datos de una semana a partir de la fecha actual. Esto debería funcionar.

Nota: Estoy convirtiendo la fecha que viene con milisegundos por 1000, y comparando después. Avísame si necesitas claridad.