有没有可能知道在iOS中使用什么介质进行共享？

Question

我正在尝试弄清楚是否有一种方法可以捕获所选的媒体以供共享。我有一个iOS应用程序，还有一个分享按钮，可以分享一个预定义的模板。当用户点击分享按钮时，他将看到可用于分享的应用程序，如果用户选择Facebook、WhatsApp或Skype，这些应用程序将被重定向到他们选择的媒体的本地应用程序。现在我想知道他们选择了什么。

Answer 1

您可以使用UIActivityViewController的completionWithItemsHandler来检查用户选择了哪种activity类型，以及他们是完成了activity还是取消了activity：

let activityViewController = UIActivityViewController(activityItems:[ "Hello"], applicationActivities: nil)

activityViewController.completionWithItemsHandler = { (activityType, completed, returnedItems, error) in

  //check completed
  if completed{
    //check activity type using activity type
    if activityType!==UIActivityTypePostToFacebook{
      //Facebook 
    }
   and so on 
  }
}
presentViewController(activityViewController, animated: true, completion: {})

Answer 2

您可以使用此代码在objective C中与UIActivityViewController进行共享

- (IBAction)shareButton:(UIBarButtonItem *)sender
{
   NSString *textToShare = @"Look at this awesome website for aspiring iOS Developers!";
NSURL *myWebsite = [NSURL URLWithString:@"http://www.codingexplorer.com/"];

NSArray *objectsToShare = @[textToShare, myWebsite];

UIActivityViewController *activityVC = [[UIActivityViewController alloc] initWithActivityItems:objectsToShare applicationActivities:nil];

NSArray *excludeActivities = @[UIActivityTypeAirDrop,
                               UIActivityTypePrint,
                               UIActivityTypeAssignToContact,
                               UIActivityTypeSaveToCameraRoll,
                               UIActivityTypeAddToReadingList,
                               UIActivityTypePostToFlickr,
                               UIActivityTypePostToVimeo];

activityVC.excludedActivityTypes = excludeActivities;

[self presentViewController:activityVC animated:YES completion:nil];
}

在使用UIActivityViewController的Swift中：

@IBAction func shareButtonClicked(sender: UIButton) {
let textToShare = "Swift is awesome!  Check out this website about it!"

if let myWebsite = NSURL(string: "http://www.codingexplorer.com/") {
    let objectsToShare = [textToShare, myWebsite]
    let activityVC = UIActivityViewController(activityItems: objectsToShare, applicationActivities: nil)

    //New Excluded Activities Code
    activityVC.excludedActivityTypes = [UIActivityTypeAirDrop, UIActivityTypeAddToReadingList]
    //

    activityVC.popoverPresentationController?.sourceView = sender
    self.presentViewController(activityVC, animated: true, completion: nil)
}
}

如果你想在facebook上长期分享，你可以在objective C中使用SLComposeViewController

 if ([SLComposeViewController isAvailableForServiceType:SLServiceTypeFacebook]) {
    fbSLComposeViewController = [SLComposeViewController composeViewControllerForServiceType:SLServiceTypeFacebook];
    [fbSLComposeViewController addImage:someImage];
    [fbSLComposeViewController setInitialText:@"Some Text"];
    [self presentViewController:fbSLComposeViewController animated:YES completion:nil];

    fbSLComposeViewController.completionHandler = ^(SLComposeViewControllerResult result) {
        switch(result) {
            case SLComposeViewControllerResultCancelled:
                NSLog(@"facebook: CANCELLED");
                break;
            case SLComposeViewControllerResultDone:
                NSLog(@"facebook: SHARED");
                break;
        }
    };
}
else {
    UIAlertView *fbError = [[UIAlertView alloc] initWithTitle:@"Facebook Unavailable" message:@"Sorry, we're unable to find a Facebook account on your device.\nPlease setup an account in your devices settings and try again." delegate:self cancelButtonTitle:@"Close" otherButtonTitles:nil];
    [fbError show];
}

Swift中的SLComposeViewController

 @IBAction func facebookButtonPushed(sender: UIButton) {
if SLComposeViewController.isAvailableForServiceType(SLServiceTypeFacebook){
    var facebookSheet:SLComposeViewController = SLComposeViewController(forServiceType: SLServiceTypeFacebook)
    facebookSheet.setInitialText("Share on Facebook")
    self.presentViewController(facebookSheet, animated: true, completion: nil)
} else {
    var alert = UIAlertController(title: "Accounts", message: "Please login to a Facebook account to share.", preferredStyle: UIAlertControllerStyle.Alert)
    alert.addAction(UIAlertAction(title: "OK", style: UIAlertActionStyle.Default, handler: nil))
    self.presentViewController(alert, animated: true, completion: nil)
}
}