Ios 使用UIActivityViewController提供缩略图图像

我正试图通过

UIActivityViewController

与文本共享图像。如果我这样做：

        let activityVC = UIActivityViewController(activityItems: [text, image], applicationActivities: nil)
        self.presentViewController(activityVC, animated: true, completion: nil)

let activityVC = UIActivityViewController(activityItems: [self, self], applicationActivities: nil)

一切正常。问题是，我只想与某些活动类型共享映像。i、 当一个用户分享到Facebook时，我不想拥有一张图片，尽管我做了其他的事情。我的问题是这个愚蠢的方法从未被调用：

optional func activityViewController(_ activityViewController: UIActivityViewController,
       thumbnailImageForActivityType activityType: String?,
                       suggestedSize size: CGSize) -> UIImage?

这应该是因为它是在

UIActivityItemSource

协议中定义的。这有什么办法吗

---

因此，我相信在这方面已经取得了一些进展。如果在实例化

UIActivityViewController

时传递了

self

的多个值，则可以在

itemForActivityType

委托方法中返回多个值。因此，如果我这样做：

        let activityVC = UIActivityViewController(activityItems: [text, image], applicationActivities: nil)
        self.presentViewController(activityVC, animated: true, completion: nil)

let activityVC = UIActivityViewController(activityItems: [self, self], applicationActivities: nil)

我可以像这样返回不同的值：

func activityViewController(activityViewController: UIActivityViewController, itemForActivityType activityType: String) -> AnyObject? {
    if activityType == UIActivityTypePostToFacebook {
        return ["hello", "world"]
    }
    else {
        return ["goodnight", "moon"]
    }
}

但是，似乎只能返回两个相同类型的值

---

现在我的新问题是，如何同时返回图像和文本？？搜寻继续…

为了共享两组不同的内容，您必须创建两个不同的itemsource

我们可以为不同的活动类型设置不同的文本内容。将MyStringItemSource类添加到您的viewcontroller中

SourceOne:

class MyStringItemSource: NSObject, UIActivityItemSource {

@objc func activityViewControllerPlaceholderItem(activityViewController: UIActivityViewController) -> AnyObject {
    return ""
}

@objc func activityViewController(activityViewController: UIActivityViewController, itemForActivityType activityType: String) -> AnyObject? {
    //You can pass different text for for diffrent activity type
    if activityType == UIActivityTypePostToFacebook {
        return "String for facebook"
    }else{
        return "String for Other"
    }
  }
}

class MyImageItemSource: NSObject, UIActivityItemSource {

@objc func activityViewControllerPlaceholderItem(activityViewController: UIActivityViewController) -> AnyObject {
   return ""
}


@objc func activityViewController(activityViewController:  UIActivityViewController, itemForActivityType activityType: String) -> AnyObject? {
  //This one allows us to share image ecxept UIActivityTypePostToFacebook
  if activityType == UIActivityTypePostToFacebook {
     return nil
  }
  let Image: UIImage = UIImage(data: NSData(contentsOfURL: NSURL(string: "https://pbs.twimg.com/profile_images/604644048/sign051.gif")!)!)!
      return Image
  }   

}

我们的要求是将图像添加到除FB之外的所有活动类型，以便在VC中添加MyImageItemSource类

来源二：

class MyStringItemSource: NSObject, UIActivityItemSource {

@objc func activityViewControllerPlaceholderItem(activityViewController: UIActivityViewController) -> AnyObject {
    return ""
}

@objc func activityViewController(activityViewController: UIActivityViewController, itemForActivityType activityType: String) -> AnyObject? {
    //You can pass different text for for diffrent activity type
    if activityType == UIActivityTypePostToFacebook {
        return "String for facebook"
    }else{
        return "String for Other"
    }
  }
}

class MyImageItemSource: NSObject, UIActivityItemSource {

@objc func activityViewControllerPlaceholderItem(activityViewController: UIActivityViewController) -> AnyObject {
   return ""
}


@objc func activityViewController(activityViewController:  UIActivityViewController, itemForActivityType activityType: String) -> AnyObject? {
  //This one allows us to share image ecxept UIActivityTypePostToFacebook
  if activityType == UIActivityTypePostToFacebook {
     return nil
  }
  let Image: UIImage = UIImage(data: NSData(contentsOfURL: NSURL(string: "https://pbs.twimg.com/profile_images/604644048/sign051.gif")!)!)!
      return Image
  }   

}

现在我们已经准备好设置UIActivityViewController，开始吧

@IBAction func Test(sender: AnyObject) {

let activityVC = UIActivityViewController(activityItems: [MyStringItemSource(),MyImageItemSource()] as [AnyObject], applicationActivities: nil)

//Instead of using rootviewcontroller go with your own way.
if let window = (UIApplication.sharedApplication().delegate as? AppDelegate)?.window
{
    window.rootViewController?.presentViewController(activityVC, animated: true, completion: nil)
}
}

推特共享对话： 包含图像和给定文本

FB共享对话： 仅包含给定的文本