Swift中的ABMultiValue地址簿多值属性编译错误

Question

代码在Objective中工作，试图转换为Swift。我提供了工作目标-C代码和Swift代码，它们在第10行( for subValue in aPropertyValue ...快速枚举器)上产生了编译错误。快速错误“类型'ABMultiValue‘不符合协议'SequenceType'”。

一些ABPerson属性可能包含多个值(例如，多个电话号码)，并且是ABMultiValue类的对象(尽管Xcode调试器将它们报告为ABMultiValueCoreDataWrapper类)。附加的Objective代码循环通过多个值。我试图在Swift中做同样的事情，但是无法通过编译错误。两者都是Xcode命令行项目。

目标-C代码：

#import <Foundation/Foundation.h>
#import <AddressBook/AddressBook.h>
int main(int argc, const char * argv[]) {
    @autoreleasepool {
        ABAddressBook *addressBook = [ABAddressBook sharedAddressBook];
        NSArray *people = [addressBook people];
        for (ABPerson *person in people) {
            for (NSString *aProperty in [ABPerson properties]) {
                id aPropertyValue = [person valueForProperty: aProperty];
                if ([aPropertyValue isKindOfClass: [ABMultiValue class]]) {
                    for (id subValue in aPropertyValue) {
                        NSLog(@"%@",subValue);
                    }
                }
            }
        }
    }
    return 0;
}

快速代码：

import Foundation
import AddressBook
let addressBook = ABAddressBook.sharedAddressBook()
let people = addressBook.people()
for person in people {
    for property in ABPerson.properties() {
        if let aPropertyValue : AnyObject = person.valueForProperty(property as NSString) {
            if aPropertyValue is ABMultiValue {
//                for subValue in aPropertyValue {
                for subValue in aPropertyValue as ABMultiValue {
                    println("\(subValue)") 
                }
            }
        }
    }
}

Answer 1

显然，您可以使用该索引：

let addressBook = ABAddressBook.sharedAddressBook()
let people = addressBook.people()
for person in people {
    for property in ABPerson.properties() {
        if let multiValue = person.valueForProperty(property as NSString) as? ABMultiValue {
            for i in 0 ..< multiValue.count() {
                println(multiValue.valueAtIndex(i))
            }
        }
    }
}

或者，按照this answer中的建议，您可以定义一个符合SequenceType的扩展

extension ABMultiValue: SequenceType {
    public func generate() -> NSFastGenerator {
        return NSFastGenerator(self)
    }
}

然后你就可以：

let addressBook = ABAddressBook.sharedAddressBook()
let people = addressBook.people()
for person in people {
    for property in ABPerson.properties() {
        if let multiValue = person.valueForProperty(property as NSString) as? ABMultiValue {
            for identifier in multiValue {
                let value: AnyObject = multiValue.valueForIdentifier(identifier as String)
                println("\(identifier) : \(value)")
            }
        }
    }
}