© 2018 Domizio DemichelisMIT License

Support Extra

This extra adds support for features like countless or navless pagination, where you don’t need the full link bar but only a simple next or prev link or no link at all (like for auto-scroll).

It also provides a couple of helpers to setup you own custom javascript components.

Synopsis

See extras for general usage info.

In the pagy.rb initializer:

require 'pagy/extras/support'

Support for alternative pagination types and features

Besides the classic navbar pagination, the compact and the responsive UI components, Pagy offers a few helpers to support a few alternative types of pagination and related features.

Countless

You can totally avoid one query per render by using the countless extra. It has a few limitation, but still supports navbar links (see also Pagy::Countless for more details).

If you don’t need the navbar you can just set the :size variable to an empty value and the page links will be skipped from the rendering. That works with Pagy and Pagy:Countless instances. All the *nav helpers will render only the prev and next links/buttons, allowing for a manual incremental pagination.

You can also use the pagy_prev_link and pagy_next_link helpers provided by this extra, mostly useful if you also use the countless extra.

Circular/Infinite

This type of pagination sets the next page to 1 when the current page is the last page, allowing an infinite loop through the pages.

For example, it is often used to show a few suggestions of “similar products” in a horizontal stripe of just a few page of a few items each. Clicking on next will continue to loop through.

For example:

@pagy, @suggestions = Pagy.new(count: 25, items: 5, cycle: true)

Passing a forced :count of 25 will generate 5 pages of 5 items each that will always have a next page. Regardless the actual collection count, you will show the first 25 items of the collection, looping in stripes of 5 items each.

You may want to combine it with something like:

<%== pagy_next_link(@pagy, 'More...')

Auto-scroll

Pagy supports auto-scroll pagination by providing the pagy_apply_init_tag helper, which initializes your custom pagination elements by calling your custom defined javascript function at page load.

Custom UIs

You can use the pagy_prev_url and pagy_next_url to build your own links or buttons. Besides, with the pagy_apply_init_tag and pagy_serialized helpers you can also setup you own custom javascript components.

Methods

pagy_prev_url(pagy)

Returns the url for the previous page. Useful to build minimalistic UIs that don’t use nav bar links (e.g. countless extra).

pagy_next_url(pagy)

Returns the url for the next page. Useful to build minimalistic UIs that don’t use nav bar links (e.g. countless extra).

Returns the link for the next page. It is the same prev link string which is part of the pagy_nav helper.

Useful to build minimalistic helpers UIs that don’t use nav bar links (e.g. countless extra).

Returns the link for the next page. It is the same next link string which is part of the pagy_nav helper.

Useful to build minimalistic helpers UIs that don’t use nav bar links (e.g. countless extra).

pagy_serialized(pagy)

Returns a hash with all the instance variables, series, prev_url and next_url of the pagy argument. Useful to use in some client-side javascript. It’s the default payload of pagy_apply_init_tag.

pagy_apply_init_tag(pagy, function, payload=…)

This is a multi-purpose helper that generates a JSON tag that will be loaded and exececuted by the Pagy.init javascript function at document load (see Javascript).

The method requires a pagy object, a javascript function name and accepts an optional payload (default to the hash returned by pagy_serialized method) that will get passed to the function. For example:

# this uses the serialized pagy object as the default payload
pagy_apply_init_tag(@pagy, :myInitFunction)

# this uses a custom payload
pagy_apply_init_tag(@pagy, :myOtherFunction, {a: 1, b: 2})

You should define your functions in the PagyInit namespace, as follow, using the payload as needed:

PagyInit.myInitFunction = function(payload){
  console.log(payload);
  doSomethingWith(payload);
  ...
}

You can use it to initialize your custom pagination elements. For auto-scroll, you may want to update some client side variable with the pagy_next_url at each page load.