Knockout paging binding

Question

Sorry if this is a really basic question but I'm in the process of learning Knockout and trying to wire up paging to my dataset.

In my code below, you will see that I am retrieving the dataset, and the page size dropdown affects the results appropriately.
And when I change the page number (#'d links in footer of table), nothing happens.
Could someone tell me what I'm missing?

function ViewModel(){
    var vm = this;

    // variables
    vm.drinks = ko.observableArray();
    vm.pageSizes = [15,25,35,50];
    vm.pageSize = ko.observable(pageSizes[0]);
    vm.currentPage = ko.observable(0);

    // computed variables
    // returns number of pages required for number of results selected
    vm.PageCount = ko.computed(function(){
        if(vm.pageSize()){
            return Math.ceil(vm.drinks().length / vm.pageSize());
        }else{
            return 1;
        }
    });

    // returns items from the array for the current page
    vm.PagedResults = ko.computed(function(){
        //return vm.drinks().slice(vm.currentPage, vm.pageSize());
        return vm.drinks().slice(vm.currentPage() * vm.pageSize(), (vm.currentPage() * vm.pageSize()) + vm.pageSize());
    });

    // returns a list of numbers for all pages
    vm.PageList = ko.computed(function(){
        if(vm.PageCount() > 1){
            return Array.apply(null, {length: vm.PageCount()}).map(Number.call, Number);
        }
    });

    // methods
    vm.ResetCurrentPage = function(){
        vm.currentPage(0);
    }

    // go to page number
    vm.GoToPage = function(page){
        vm.currentPage(page);
    }

    // populate drink list
    vm.GetDrinks = function(){
        // get data
        $(function () {
            $.ajax({
                type: "GET",
                url: 'https://mysafeinfo.com/api/data?list=alcoholicbeverages&format=json',
                dataType: "json",
                success: function (data) {
                    vm.drinks(data);
                }
            });
        });
    }

    // populate drinks
    vm.GetDrinks();
}

// apply bindings
ko.applyBindings(ViewModel);







    
        
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jay · Accepted Answer

Thanks to f_martinez for helping with my issue, here is the working example if anyone ends up here looking for how to do paging. jsfiddle

I will keep this open for now in case f_martinez would like to post an answer to accept.

function ViewModel() {
  var vm = this;

  // variables  
  vm.drinks = ko.observableArray();
  vm.pageSizes = [15, 25, 35, 50];
  vm.pageSize = ko.observable(pageSizes[0]);
  vm.currentPage = ko.observable(0);

  // computed variables
  // returns number of pages required for number of results selected
  vm.PageCount = ko.computed(function() {
    if (vm.pageSize()) {
      return Math.ceil(vm.drinks().length / vm.pageSize());
    } else {
      return 1;
    }
  });

  // returns items from the array for the current page
  vm.PagedResults = ko.computed(function() {
    if (vm.PageCount() > 1) {
      //return vm.drinks().slice(vm.currentPage, vm.pageSize());
      return vm.drinks().slice(vm.currentPage() * vm.pageSize(), (vm.currentPage() * vm.pageSize()) + vm.pageSize());
    } else {
      return vm.drinks();
    }
  });

  // returns a list of numbers for all pages
  vm.PageList = ko.computed(function() {
    if (vm.PageCount() > 1) {
      return Array.apply(null, {
        length: vm.PageCount()
      }).map(Number.call, Number);
    }
  });

  // methods
  // reset to first page
  vm.ResetCurrentPage = function() {
    vm.currentPage(0);
  }

  // go to page number
  vm.GoToPage = function(page) {
    vm.currentPage(page);
  }

  // determines if page # is active returns active class
  vm.GetClass = function(page) {
    return (page == vm.currentPage()) ? "active" : "";
  }

  // populate drink list
  vm.GetDrinks = function() {
    // get data
    $(function() {
      $.ajax({
        type: "GET",
        url: 'https://mysafeinfo.com/api/data?list=alcoholicbeverages&format=json',
        dataType: "json",
        success: function(data) {
          vm.drinks(data);
        }
      });
    });
  }

  // populate drinks
  vm.GetDrinks();
}

// apply bindings
ko.applyBindings(ViewModel);

.pagination > li > a:focus,
.pagination > li > a:hover,
.pagination > li > span:focus,
.page-link.active {
  background-color: rgb(238, 238, 238);
}







  
    
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      Name
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Knockout paging binding

Answers (2)

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