# Flop Phoenix
 [](https://hex.pm/packages/flop_phoenix) [](https://coveralls.io/github/woylie/flop_phoenix)
Flop Phoenix is an Elixir library for filtering, ordering and pagination
with Ecto, Phoenix and [Flop](https://hex.pm/packages/flop).
## Installation
Add `flop_phoenix` to your list of dependencies in the `mix.exs` of your Phoenix
application:
```elixir
def deps do
[
{:flop_phoenix, "~> 0.7.0"}
]
end
```
Follow the instructions in the
[Flop documentation](https://hex.pm/packages/flop) to set up your business
logic.
## Usage
In your controller, pass the data and the Flop meta struct to your template:
```elixir
defmodule MyAppWeb.PetController do
use MyAppWeb, :controller
alias Flop
alias MyApp.Pets
alias MyApp.Pets.Pet
action_fallback MyAppWeb.FallbackController
def index(conn, params) do
with {:ok, {pets, meta}} <- Pets.list_pets(params) do
render(conn, "index.html", meta: meta, pets: pets)
end
end
end
```
In `my_app_web.ex`, find the `view_helpers/0` macro and import `Flop.Phoenix`:
```diff
defp view_helpers do
quote do
# Use all HTML functionality (forms, tags, etc)
use Phoenix.HTML
# Import basic rendering functionality (render, render_layout, etc)
import Phoenix.View
+ import Flop.Phoenix
import MyAppWeb.ErrorHelpers
import MyAppWeb.Gettext
alias MyAppWeb.Router.Helpers, as: Routes
end
end
```
In your index template, you can now add a sortable table and pagination links:
```elixir
<h1>Pets</h1>
<%= table(%{
items: @pets,
meta: @meta,
path_helper: &Routes.pet_path/3,
path_helper_args: [@conn, :index],
headers: [{"Name", :name}, {"Age", :age}],
row_func: fn pet, _opts -> [pet.name, pet.age] end,
opts: [for: MyApp.Pet]
})
%>
<%= pagination(@meta, &Routes.pet_path/3, [@conn, :index]) %>
```
The second argument of `Flop.Phoenix.pagination/4` is the path helper function,
and the third argument is a list of arguments for that path helper. If you
want to add path parameters, you can do it like this:
```elixir
<%= pagination(@meta, &Routes.owner_pet_path/4, [@conn, :index, @owner]) %>
```
This works the same as the `path_helper` and `path_helper_args` values of
`Flop.Phoenix.table/1`.
To keep your template clean, it is recommended to define a `table_headers/1`
and `table_row/2` function in your view. The `opts` are passed as a second
argument to the `row_func`, so you can add any additional parameters you need.
The view module:
```elixir
defmodule MyApp.PetView do
def table_headers do
[
# {display value, schema field}
{"Name", :name},
{"Age", :age},
""
]
end
def table_row(%Pet{} = pet, opts) do
conn = Keyword.fetch!(opts, :conn)
[
pet.name,
pet.age,
link "show", to: Routes.pet_path(conn, :show, pet)
]
end
end
```
The template:
```elixir
<%= table(%{
items: @pets,
meta: @meta,
path_helper: &Routes.pet_path/3,
path_helper_args: [@conn, :index],
headers: table_headers(),
row_func: &table_row/2,
opts: [conn: @conn, for: Pet]
})
%>
```
## Customization
If you want to customize the pagination or table markup, you would probably want
to do that once for all templates. To do that, create a new file
`views/flop_helpers.ex` (or maybe `views/component_helpers.ex`).
```elixir
defmodule MyAppWeb.FlopHelpers do
use Phoenix.HTML
def pagination(meta, route_helper, route_helper_args) do
opts = [
next_link_content: next_icon(),
previous_link_content: previous_icon(),
wrapper_attrs: [class: "paginator"]
]
Flop.Phoenix.pagination(meta, route_helper, route_helper_args, opts)
end
defp next_icon do
tag :i, class: "fas fa-chevron-right"
end
defp previous_icon do
tag :i, class: "fas fa-chevron-left"
end
end
```
Change the import in `my_app_web.ex`:
```diff
defp view_helpers do
quote do
# ...
- import Flop.Phoenix
+ import MyAppWeb.FlopHelpers
# ...
end
end
```
You can do it similarly for `Flop.Phoenix.table/1`
Refer to the `Flop.Phoenix` module documentation for more examples.
