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iOS

Mohammad A
Mohammad A
1,895 Points
Posted by Mohammad A
Mohammad A
1,895 Points

blog but with 1000 posts

Hi,

How can I make a blog reader app retrieve 1000 posts without letting the user wait for a long time?

I have checked the lazytableimages from apple and I can download all the posts but that comes on the expense of user time.

Please assist.

Thanks.

agreatdaytocode
agreatdaytocode
24,757 Points

You should use Grand Central Dispatch

https://developer.apple.com/library/ios/documentation/Performance/Reference/GCD_libdispatch_Ref/Reference/reference.html

Hope that helps.

2 Answers

Amit Bijlani
STAFF
Amit Bijlani
Treehouse Guest Teacher
Amit Bijlani
Amit Bijlani
Treehouse Guest Teacher

Mohammad A you probably want to have some kind of paging so you don't download thousand items in one go. As for asynchronous, I have created a video explaining how you can asynchronously load data using the Blog Reader app as an example:

It uses NSURLSession and NSURLSessionDownloadTask

Kieran Robinson
Kieran Robinson
9,411 Points
Kieran Robinson
Kieran Robinson
9,411 Points

Hi Amit Bijlani, is this possible with things not downloaded from the web? for example I have images on a tableview cell that the user inputs from their photo roll or camera. however due to the amount of images the page can be sluggish to scroll. Can i multithread the image loading so that it is quicker to scroll? Kieran

M T
M T
11,934 Points
M T
M T
11,934 Points

Amit Bijlani, is there a handy place I can find the rest of your tips videos? This was great, thank you.

Thomas Nilsen
Thomas Nilsen
14,957 Points
Thomas Nilsen
Thomas Nilsen
14,957 Points

Maybe try to download it asynchronously, and not do it on the main thread. That way your app will still be functional while thing is finishing up in the background.

Mohammad A
Mohammad A
1,895 Points
Mohammad A
Mohammad A
1,895 Points

I'm doing it all asynchronously. I have 1000 posts with images all in a tableview. First I download and parse JSON data; titles and links to images of 1000 posts (not in the main thread), and then when the user scroll down, download of images begin.

The download of JSON data is the problem. I do not know how can I divide the download process and then update the tableview smoothly.