on screen loader in ionic framework from wordpress json api with onload function

for example-in category "news" of my blog there are 50 posts. For get last 10 posts with loader I do: http://mywordpress.com/?json=get_category_posts&slug=news&count=10&status=publish And it work correctly with loader.Now I want to get my posts from 11 to 20 ,21 to 30 in one list with onscreen loader. How can I do?