How to integrate latest SDWebImage API in my Swift

问题:

I have used SDWebImage with Objective C and it worked great for me but now I am learning Swift and trying to integrate the latest version of the API but I am stucking at every step as API is in Objective C and there are no steps mentioned to use the API with Swift. I read the documents and created the bridge header file and included the required file like below:

#ifndef MyProject_Bridging_Header_h
#define MyProject_Bridging_Header_h

#import <SDWebImage/UIImageView+WebCache.h>
#import "UIImageView+WebCache.h"

#endif

I have added the frameworks as well and dragged the SDWebImage project within my app as explained here

I am really struggling in this. Please help! For reference I have added an image showing the error!

回答1:

Here is a code example that should work :

let block: SDWebImageCompletionBlock! = {(image: UIImage!, error: NSError!, cacheType: SDImageCacheType!, imageURL: NSURL!) -> Void in
    println(self)
}

let url = NSURL(string: "http://placehold.it/350x150")

self.imageView.sd_setImageWithURL(url, completed: block)

and in your bridging header file :

#import "UIImageView+WebCache.h"

So your bridging header file should work, but sometimes I had trouble with the bridging header and in theses cases I just delete it, and add it again and everything works fine after.

回答2:

The best option will be to drag and drop SDWebImage folder to project. Make sure 'copy items if needed' is ticked on.

Make a Obj C Bridging:File -> New -> Source -> Header File -> Name as AppName-Bridging-Header.

Add the following:

        #ifndef AppName_AppName_Bridging_Header_h
        #define AppName_AppName_Bridging_Header_h

        #import <SDWebImage/UIImageView+WebCache.h>
        #import "UIImageView+WebCache.h"
        #endif

    or

 #import "UIImageView+WebCache.h"   

Reference: https://developer.apple.com/library/ios/documentation/Swift/Conceptual/BuildingCocoaApps/MixandMatch.html

Note: Build Settings, in Swift Compiler - Code Generation, make sure the Objective-C Bridging Header build setting under has a path to the bridging header file. - its like testSD/testSD-Bridging-Header.h or testSD-Bridging-Header.h (Open the Project folder and find the header file path)

Now try with this code:

let block: SDWebImageCompletionBlock! = {(image: UIImage!, error: NSError!, cacheType: SDImageCacheType!, imageURL: NSURL!) -> Void in
    println(self)
}

let url = NSURL(string: "http://arrow_upward.com/350x150")
self.imageView.sd_setImageWithURL(url, completed: block)

Suppose if you are using a UICollectionView to populate Cache imaging, try with this code.

func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {
        let cell = photoListCollectionView.dequeueReusableCellWithReuseIdentifier("scoutimagecellidentifier", forIndexPath: indexPath) as! ScoutImageCell

        //Loading image from server using SDWebImage library
        let thumbImageUrl  =   NSURL(string: self.photoPropertyArray[indexPath.row] as String)

        //Image Fetching is done in background GCD thread        

SDWebImageManager.sharedManager().downloadImageWithURL(thumbImageUrl, options: [],progress: nil, completed: {[weak self] (image, error, cached, finished, url) in

if let wSelf = self {

                //On Main Thread
                dispatch_async(dispatch_get_main_queue()){
                    cell.scoutimage.image = image
                    cell.photoloader.stopAnimating()
                }
            }
            })
        return cell
    }

回答3:

swift 3.0 code

import SDWebImage

let url = URL.init(string:"https://vignette3.wikia.nocookie.net/zelda/images/b/b1/Link_%28SSB_3DS_%26_Wii_U%29.png")
imagelogo.sd_setImage(with: url , placeholderImage: nil)