Phoenix.LiveView.Helpers (Phoenix LiveView v0.15.7) View Source
A collection of helpers to be imported into your views.
Link to this section Summary
Functions
Renders a component defined by the given function.
Renders a Phoenix.LiveComponent
within a parent LiveView.
Builds a file input tag for a LiveView upload.
Returns the flash message from the LiveView flash assign.
Generates an image preview on the client for a selected file.
Generates a link that will patch the current LiveView.
Generates a link that will redirect to a new LiveView.
Renders a LiveView within an originating plug request or within a parent LiveView.
Renders a title tag with automatic prefix/suffix on @page_title
updates.
Renders the @inner_block
assign of a component with the given argument
.
Provides ~L
sigil with HTML safe Live EEx syntax inside source files.
Returns the entry errors for an upload.
Returns the entry errors for an upload.
Link to this section Functions
Renders a component defined by the given function.
It takes two optional arguments, the assigns to pass to the given function
and a do-block - which will be converted into a @inner_block
assign (see
render_block/3
for more information).
The given function must expect one argument, which are the assigns
as a
map.
Examples
The function can be either local:
<%= component(&weather_component/1, city: "Kraków") %>
Or remote:
<%= component(&MyApp.Weather.component/1, city: "Kraków") %>
Renders a Phoenix.LiveComponent
within a parent LiveView.
While LiveView
s can be nested, each LiveView starts its
own process. A LiveComponent provides similar functionality
to LiveView, except they run in the same process as the
LiveView
, with its own encapsulated state.
LiveComponent comes in two shapes, stateful and stateless.
See Phoenix.LiveComponent
for more information.
Examples
All of the assigns
given are forwarded directly to the
live_component
:
<%= live_component(MyApp.WeatherComponent, id: "thermostat", city: "Kraków") %>
Note the :id
won't necessarily be used as the DOM ID.
That's up to the component. However, note that the :id
has
a special meaning: whenever an :id
is given, the component
becomes stateful. Otherwise, :id
is always set to nil
.
Builds a file input tag for a LiveView upload.
Options may be passed through to the tag builder for custom attributes.
Drag and Drop
Drag and drop is supported by annotating the droppable container with a phx-drop-target
attribute pointing to the DOM ID of the file input. By default, the file input ID is the
upload ref
, so the following markup is all that is required for drag and drop support:
<div class="container" phx-drop-target="<%= @uploads.avatar.ref %>">
...
<%= live_file_input @uploads.avatar %>
</div>
Examples
<%= live_file_input @uploads.avatar %>
Returns the flash message from the LiveView flash assign.
Examples
<p class="alert alert-info"><%= live_flash(@flash, :info) %></p>
<p class="alert alert-danger"><%= live_flash(@flash, :error) %></p>
Generates an image preview on the client for a selected file.
Examples
<%= for entry <- @uploads.avatar.entries do %>
<%= live_img_preview entry, width: 75 %>
<% end %>
Generates a link that will patch the current LiveView.
When navigating to the current LiveView,
Phoenix.LiveView.handle_params/3
is
immediately invoked to handle the change of params and URL state.
Then the new state is pushed to the client, without reloading the
whole page while also maintaining the current scroll position.
For live redirects to another LiveView, use live_redirect/2
.
Options
:to
- the required path to link to.:replace
- the flag to replace the current history or push a new state. Defaultsfalse
.
All other options are forwarded to the anchor tag.
Examples
<%= live_patch "home", to: Routes.page_path(@socket, :index) %>
<%= live_patch "next", to: Routes.live_path(@socket, MyLive, @page + 1) %>
<%= live_patch to: Routes.live_path(@socket, MyLive, dir: :asc), replace: false do %>
Sort By Price
<% end %>
Generates a link that will redirect to a new LiveView.
The current LiveView will be shut down and a new one will be mounted
in its place, without reloading the whole page. This can
also be used to remount the same LiveView, in case you want to start
fresh. If you want to navigate to the same LiveView without remounting
it, use live_patch/2
instead.
Options
:to
- the required path to link to.:replace
- the flag to replace the current history or push a new state. Defaultsfalse
.
All other options are forwarded to the anchor tag.
Examples
<%= live_redirect "home", to: Routes.page_path(@socket, :index) %>
<%= live_redirect "next", to: Routes.live_path(@socket, MyLive, @page + 1) %>
<%= live_redirect to: Routes.live_path(@socket, MyLive, dir: :asc), replace: false do %>
Sort By Price
<% end %>
Renders a LiveView within an originating plug request or within a parent LiveView.
Options
:session
- the map of extra session data to be serialized and sent to the client. Note that all session data currently in the connection is automatically available in LiveViews. You can use this option to provide extra data. Also note that the keys in the session are strings keys, as a reminder that data has to be serialized first.:container
- an optional tuple for the HTML tag and DOM attributes to be used for the LiveView container. For example:{:li, style: "color: blue;"}
. By default it uses the module definition container. See the "Containers" section below for more information.:id
- both the DOM ID and the ID to uniquely identify a LiveView. An:id
is automatically generated when rendering root LiveViews but it is a required option when rendering a child LiveView.:router
- an optional router that enables this LiveView to perform live navigation. Only a single LiveView in a page may have the:router
set. LiveViews defined at the router with thelive
macro automatically have the:router
option set.
Examples
# within eex template
<%= live_render(@conn, MyApp.ThermostatLive) %>
# within leex template
<%= live_render(@socket, MyApp.ThermostatLive, id: "thermostat") %>
Containers
When a LiveView
is rendered, its contents are wrapped in a container.
By default, said container is a div
tag with a handful of LiveView
specific attributes.
The container can be customized in different ways:
You can change the default
container
onuse Phoenix.LiveView
:use Phoenix.LiveView, container: {:tr, id: "foo-bar"}
You can override the container tag and pass extra attributes when calling
live_render
(as well as on yourlive
call in your router):live_render socket, MyLiveView, container: {:tr, class: "highlight"}
Renders a title tag with automatic prefix/suffix on @page_title
updates.
Examples
<%= live_title_tag assigns[:page_title] || "Welcome", prefix: "MyApp – " %>
<%= live_title_tag assigns[:page_title] || "Welcome", suffix: " – MyApp" %>
Renders the @inner_block
assign of a component with the given argument
.
<%= render_block(@inner_block, value: @value)
Provides ~L
sigil with HTML safe Live EEx syntax inside source files.
iex> ~L"""
...> Hello <%= "world" %>
...> """
{:safe, ["Hello ", "world", "\n"]}
Returns the entry errors for an upload.
The following errors may be returned:
:too_many_files
- The number of selected files exceeds the:max_entries
constraint
Examples
def error_to_string(:too_many_files), do: "You have selected too many files"
<%= for err <- upload_errors(@uploads.avatar) do %>
<div class="alert alert-danger">
<%= error_to_string(err) %>
</div>
<% end %>
Returns the entry errors for an upload.
The following errors may be returned:
:too_large
- The entry exceeds the:max_file_size
constraint:not_accepted
- The entry does not match the:accept
MIME types
Examples
def error_to_string(:too_large), do: "Too large"
def error_to_string(:not_accepted), do: "You have selected an unacceptable file type"
<%= for entry <- @uploads.avatar.entries do %>
<%= for err <- upload_errors(@uploads.avatar, entry) do %>
<div class="alert alert-danger">
<%= error_to_string(err) %>
</div>
<% end %>
<% end %>