public BlogsPageViewModel()
 {
     // select the category
     CategoryClicked     = new Command <CategoriesForBlog>(OnCategorySelected);
     NextPageClicked     = new Command(GetNextBlogsPage);
     PreviousPageClicked = new Command(GetPreviousBlogPage);
     pageFilter          = new BlogSpecParameters();
     GetCategoryItems();
     GetBlogsItems();
 }
        private async void OnCategorySelected(CategoriesForBlog Category)
        {
            if (Category.Id == 0)
            {
                pageFilter = new BlogSpecParameters();
            }
            else
            {
                pageFilter.PageIndex  = 1;
                pageFilter.CategoryId = Category.Id;
            }

            // remove all old Blogs and Pagination info
            UpdateBlogsAndPaginationInfo();
            GetBlogsItems();
        }