toggleIsLiked method
void toggleIsLiked ()
<p>This function add like to the post if not liked and remove the like from the post if liked.</p>
Implementation
void toggleIsLiked() \{
if (!_isLiked) \{
_postService.addLike(_postID);
\} else \{
_postService.removeLike(_postID);
\}
\}