ios - Cache Images and load on scroll in UICollectionView with SDWebImageDownloader Xamarin -

i have uicollectionview cells images downloaded url along headers. below :-

internal void updatecell(profilevalues mdata)         {               var murl = "someurl";     var manager = sdwebimagemanager.sharedmanager;    manager.imagecache.maxcacheage = 86400;             sdwebimagedownloader mdownloader = manager.imagedownloader;              var authtoken = "sometoken"";               mdownloader.sethttpheadervalue(authtoken, "authorization");             mdownloader.sethttpheadervalue("application/json; odata=verbose", "accept");             mdownloader.sethttpheadervalue("f", "x-forms_based_auth_accepted");               try             {                 mdownloader.downloadimage(                  url: new nsurl(murl),      options: sdwebimagedownloaderoptions.progressivedownload,                 progressblock: (receivedsize, expectedsize) =>                 {                     // track progress...                 },                 completedblock: (image, data, error, finished) =>                 {                      if (image != null && finished)                     {                         invokeonmainthread(() =>                         {                              this.imgprofilepic.image = image;                         });                      }                     if (error != null)                     {                         invokeonmainthread(() =>                         {                             this.imgprofilepic.image = errorimage;                             this.imgprofilepic.backgroundcolor = uicolor.fromrgb(52, 31, 71);                             //this.imgprofilepic.layer.cornerradius = this.imgprofilepic.frame.size.width / 2;                             this.imgprofilepic.clipstobounds = true;                             this.imgprofilepic.layer.borderwidth = 3.0f;                             this.imgprofilepic.layer.bordercolor = uicolor.white.cgcolor;                         });                     }                 }                 );             }             catch (exception ex)             {             }         } 

but on every scroll cells reloaded , images downloaded everytime. how can cache images , load images cache on scroll? appreciated.

use ffimageloading package & use class cachedimage place of image

var cachedimage = new cachedimage() {     horizontaloptions = layoutoptions.center,     verticaloptions = layoutoptions.center,     widthrequest = 300,     heightrequest = 300,     cacheduration = timespan.fromdays(30),     downsampletoviewsize = true,     retrycount = 0,     retrydelay = 250,     transparencyenabled = false,     source = "http://loremflickr.com/600/600/nature?filename=simple.jpg",     cachekeyfactory = new customcachekeyfactory(), };