为 UIActivityViewController Swift 设置不同的活动项

Question

我有 UIActivityViewController 有 4 个选项：消息 / 邮件 / TW / FB。 我想为每个选项发送不同的活动！

例如： 在iMessage 表中，我需要输入：String、NSURL 和UIImage。 在邮件中，我需要在主题字段中放置字符串，然后在正文中放置字符串，UIImage 和 NSURL。 在TW/FB，我想在社交帖子中放置图片，还有一些字符串和NSURL。

你知道这在 iOS8 中是否可以使用 Swift 吗？

我搜索了很多代码，没有找到最适合我的。

Answer 1

您应该利用UIActivityItemSource 协议。 UIActivityViewController 的初始化程序的 activityItems 参数接受数据对象数组或实现 UIActivityItemSource 协议的对象数组。

例如，考虑如下的项目来源。

class MyStringItemSource: NSObject, UIActivityItemSource {
    @objc func activityViewControllerPlaceholderItem(activityViewController: UIActivityViewController) -> AnyObject {
        return ""
    }

    @objc func activityViewController(activityViewController: UIActivityViewController, itemForActivityType activityType: String) -> AnyObject? {
        if activityType == UIActivityTypeMessage {
            return "String for message"
        } else if activityType == UIActivityTypeMail {
            return "String for mail"
        } else if activityType == UIActivityTypePostToTwitter {
            return "String for twitter"
        } else if activityType == UIActivityTypePostToFacebook {
            return "String for facebook"
        }
        return nil
    }

    func activityViewController(activityViewController: UIActivityViewController, subjectForActivityType activityType: String?) -> String {
        if activityType == UIActivityTypeMessage {
            return "Subject for message"
        } else if activityType == UIActivityTypeMail {
            return "Subject for mail"
        } else if activityType == UIActivityTypePostToTwitter {
            return "Subject for twitter"
        } else if activityType == UIActivityTypePostToFacebook {
            return "Subject for facebook"
        }
        return ""
    }

    func activityViewController(activityViewController: UIActivityViewController, thumbnailImageForActivityType activityType: String!, suggestedSize size: CGSize) -> UIImage! {
        if activityType == UIActivityTypeMessage {
            return UIImage(named: "thumbnail-for-message")
        } else if activityType == UIActivityTypeMail {
            return UIImage(named: "thumbnail-for-mail")
        } else if activityType == UIActivityTypePostToTwitter {
            return UIImage(named: "thumbnail-for-twitter")
        } else if activityType == UIActivityTypePostToFacebook {
            return UIImage(named: "thumbnail-for-facebook")
        }
        return UIImage(named: "some-default-thumbnail")
    }
}

以上item源根据activity类型返回不同的字符串数据对象、主题和缩略图。要使用，只需将其传递给 UIActivityViewController 初始化程序即可。

UIActivityViewController(activityItems: [MyStringItemSource()], applicationActivities: nil)

同样，您可以定义一个自定义 MyUrlItemSource 类，该类根据所选活动返回不同的 URL，并将其传递到初始化程序中。

UIActivityViewController(activityItems: [MyStringItemSource(), MyUrlItemSource()], applicationActivities: nil)

所有这些都在UIActivityViewController 和UIActivityItemSource 的官方文档中进行了概述

Answer 2

Objective-C 等价于 hennes 答案：

@interface MyStringItemSource : NSObject <UIActivityItemSource>
{

}

@end


@implementation MyStringItemSource

-(id)activityViewControllerPlaceholderItem:(UIActivityViewController *)activityViewController
{
    return @"";
}

-(id)activityViewController:(UIActivityViewController *)activityViewController itemForActivityType:(UIActivityType)activityType
{
    if (activityType == UIActivityTypeMessage) {
        return @"String for message";
    } else if (activityType == UIActivityTypeMail) {
        return @"String for mail";
    }
    return nil;
}

-(NSString *)activityViewController:(UIActivityViewController *)activityViewController subjectForActivityType:(UIActivityType)activityType
{
    if (activityType == UIActivityTypeMessage) {
        return @"Subject for message";
    } else if (activityType == UIActivityTypeMail) {
        return @"Subject for mail";
    }
    return @"";
}

-(UIImage *)activityViewController:(UIActivityViewController *)activityViewController thumbnailImageForActivityType:(UIActivityType)activityType suggestedSize:(CGSize)size
{
    if (activityType == UIActivityTypeMessage) {
        return [UIImage imageNamed: @"thumbnail-for-message"];
    } else if (activityType == UIActivityTypeMail) {
        return [UIImage imageNamed: @"thumbnail-for-mail"];
    }
    return [UIImage imageNamed: @"thumbnail-for-default"];
}

@end

Answer 3

与 hennes 相同的解决方案翻译为 swift 3

class MyStringItemSource: NSObject, UIActivityItemSource {

  public func activityViewControllerPlaceholderItem(_ activityViewController: UIActivityViewController) -> Any {
    return ""
  }

  public func activityViewController(_ activityViewController: UIActivityViewController, itemForActivityType activityType: UIActivityType) -> Any? {
    if activityType == UIActivityType.message {
      return "String for message"
    } else if activityType == UIActivityType.mail {
      return "String for mail"
    } else if activityType == UIActivityType.postToTwitter {
      return "String for twitter"
    } else if activityType == UIActivityType.postToFacebook {
      return "String for facebook"
    }
    return nil
  }

  public func activityViewController(_ activityViewController: UIActivityViewController, subjectForActivityType activityType: UIActivityType?) -> String {
    if activityType == UIActivityType.message {
      return "Subject for message"
    } else if activityType == UIActivityType.mail {
      return "Subject for mail"
    } else if activityType == UIActivityType.postToTwitter {
      return "Subject for twitter"
    } else if activityType == UIActivityType.postToFacebook {
      return "Subject for facebook"
    }
    return ""
  }

  public func activityViewController(_ activityViewController: UIActivityViewController, thumbnailImageForActivityType activityType: UIActivityType?, suggestedSize size: CGSize) -> UIImage? {
    if activityType == UIActivityType.message {
      return UIImage(named: "thumbnail-for-message")
    } else if activityType == UIActivityType.mail {
      return UIImage(named: "thumbnail-for-mail")
    } else if activityType == UIActivityType.postToTwitter {
      return UIImage(named: "thumbnail-for-twitter")
    } else if activityType == UIActivityType.postToFacebook {
      return UIImage(named: "thumbnail-for-facebook")
    }
    return UIImage(named: "some-default-thumbnail")
  }

}