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iOS

Posted by Danut Florian
Danut Florian
12,804 Points

Getting Images Using Grand Central Dispatch - cache problem

Hello everyone! I'm proud to be a noob on Treehouse. I have a question regarding the Getting Images Using Grand Central Dispatch video. Are the images downloaded with Grand Central Dispatch being cached? I tried this on a project on my own (where the images are considerably bigger than the avatars used in the tutorial) and i get weird bugs like:

  • slow download
  • whenever i scroll fast in the UITableView and don't wait until the images load, when the download is finished, i get images inserted into wrong cells.

For example: Scroll to the middle and immediately scroll back up. The first cell will have the image that's corresponding to the middle cell that didn't get to finish loading.

2 Answers

John W
John W
21,558 Points
John W
John W
21,558 Points

I've made a suggestion in this other thread. Haven't tried it myself but in theory it should work with minimal code.

Danut Florian
Danut Florian
12,804 Points
Danut Florian
Danut Florian
12,804 Points

Thank you John!