小编Swi*_*ger的帖子

我在使用NSDictionaryCoreData模型中获取对象时遇到问题.

let moc:NSManagedObjectContext = SwiftCoreDataHelper.managedObjectContext()
    let results:NSArray = SwiftCoreDataHelper.fetchEntities(NSStringFromClass(Notificatie), withPredicate: nil, managedObjectContext: moc)

    for notificatie in results
    {
        let singleNotificatie:Notificatie = notificatie as Notificatie

        let notDict:NSDictionary = ["title":notificatie.title, "fireDate":notificatie.fireDate]

    }

Cannot convert the expression's type 'NSDictionary' to type 'StringLiteralConvertible'

问题出在词典中.

为什么我不能将String转换为获取对象？有解决方案吗

我在swift项目中有一个'pickerView'对象.我确实理解Objective-c中的代码,但我不确定如何在Swift中实现它.

Objc方法

-(NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component
{
    switch (component)
    {
        case 0://Week
            return 7;
        case 1://Hour
            return 24;
        default://Minutes
            return 60;//or 7;(10 by 10) //or 13;(5 by 5)
    }
}

我只是不确定如何为titleForRow函数实现switch语句.所以stringWithFormat:@"%.2ld",(long)row问题就在于此.

-(NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component
{
    switch (component)
    {
        case 0://Week
            return _dayOfWeek[row];
        case 1://Hour
            return [NSString stringWithFormat:@"%.2ld",(long)row];
        default://Minutes
            return [NSString stringWithFormat:@"%.2ld",(long)row];//or ,row*10] //or ,row*5]
    }
}

谁能帮我.

问候,达克斯