系统 ios9.1
语言swift2.0

在app 里最常用的功能就是多媒体选择，首先我们storyboard 创建一个button 用于触发选择事件

@IBAction func selectImageAction(sender: AnyObject) {

}

这时候通常会弹出来一个ActionSheet 上面有拍照 ， 相册，录像 和取消 这几项。iOS 8 以后actionsheet 和 alertview 都统一用UIAlertController 方法调用，8.3以前actionsheet 有独立的方法 后来都废弃了。首先我们要加入actionsheet 相关delegate 如下

class ViewController: UIViewController,UIImagePickerControllerDelegate,UINavigationControllerDelegate,UIActionSheetDelegate {

}

@IBAction func selectImageAction(sender: AnyObject) {

      let actionSheetController: UIAlertController = UIAlertController(title: "请选择",message:nil,preferredStyle: .ActionSheet)

        //取消按钮
        let cancelAction: UIAlertAction = UIAlertAction(title: "取消",style: .Cancel) { action -> Void in
            //Just dismiss the action sheet
        }

        actionSheetController.addAction(cancelAction)

        //拍照
        let takePictureAction: UIAlertAction = UIAlertAction(title: "拍照",style: .Default)
            { action -> Void in


            [self .initWithImagePickView("拍照")]

        }

        actionSheetController.addAction(takePictureAction)

        //相册选择
        let choosePictureAction: UIAlertAction = UIAlertAction(title: "相册",style: .Default)
            { action -> Void in

            [self .initWithImagePickView("相册")]

        }

        actionSheetController.addAction(choosePictureAction)

        //摄像
        let moviePictureAction: UIAlertAction = UIAlertAction(title: "摄像",style: .Default)
            { action -> Void in

            [self .initWithImagePickView("摄像")]

        }

        actionSheetController.addAction(moviePictureAction)

        self.presentViewController(actionSheetController,animated: true,completion: nil)



    }

这样我们想要的actionSheet 创建完成
仔细看上面的代码你会发现 [self .initWithImagePickView(“拍照”)]
这个函数，我通过这个函数选择imagePicker 不同的参数
首先创建一个 var imagePicker : UIImagePickerController! 对象
然后实现相关方法

func initWithImagePickView(type:NSString){

        self.imagePicker = UIImagePickerController()
        self.imagePicker.delegate      = self;
        self.imagePicker.allowsEditing = true;

        switch type{
        case "拍照":
            self.imagePicker.sourceType = .Camera
            break
        case "相册":
            self.imagePicker.sourceType = .PhotoLibrary
            break
        case "录像":
            self.imagePicker.sourceType = .Camera
            self.imagePicker.videoMaximumDuration = 60 * 3
            self.imagePicker.videoQuality = .Type640x480
            self.imagePicker.mediaTypes = [String(kUTTypeMovie)]


            break
        default:
            print("error")
        }

        presentViewController(self.imagePicker,completion: nil)
    }

swift 可以支持字符串，你也可以尝试其他类型看看！一些方法跟object c 基本一样

下面实现imagepick 的 delegate 方法就可以了
如下
对了如果要引入录制视频功能话别忘记了加
MobileCoreServices.framework 库 和 import MobileCoreServices 头文件

func imagePickerController(picker: UIImagePickerController,didFinishPickingMediaWithInfo info: [String : AnyObject]) {

let mediaType = info[UIImagePickerControllerMediaType] as! String

        let compareResult = CFStringCompare(mediaType as NSString!,kUTTypeMovie,CFStringCompareFlags.CompareCaseInsensitive)

        //判读是否是视频还是图片
        if compareResult == CFComparisonResult.CompareEqualTo {

            let moviePath = info[UIImagePickerControllerMediaURL] as? NSURL

            //获取路径
            let moviePathString = moviePath!.relativePath

            if UIVideoAtPathIsCompatibleWithSavedPhotosAlbum(moviePathString!)
            {

                UISaveVideoAtPathToSavedPhotosAlbum(moviePathString!,nil,nil)

            }

            print("视频")

        }
        else {

            print("图片")
        let image = info[UIImagePickerControllerOriginalImage] as? UIImage
        self.imageView.image =  image;

        }

        imagePicker.dismissViewControllerAnimated(true,completion: nil)


    }

这样一个多媒体选择功能基本实现了！