Add new Flash module to handle sending flashes from components, and receiving them in LiveViews

Author: sevenseacat

lib/phoenix_liveview_flash_components_example_web.ex

@@ -54,6 +54,8 @@ defmodule PhoenixLiveviewFlashComponentsExampleWeb do
       use Phoenix.LiveView,
         layout: {PhoenixLiveviewFlashComponentsExampleWeb.Layouts, :app}
 
+      on_mount PhoenixLiveviewFlashComponentsExampleWeb.Flash
+
       unquote(html_helpers())
     end
   end
@@ -62,6 +64,8 @@ defmodule PhoenixLiveviewFlashComponentsExampleWeb do
     quote do
       use Phoenix.LiveComponent
 
+      import PhoenixLiveviewFlashComponentsExampleWeb.Flash, only: [put_flash!: 3]
+
       unquote(html_helpers())
     end
   end

lib/phoenix_liveview_flash_components_example_web/components/first_component.ex

@@ -21,6 +21,6 @@ defmodule PhoenixLiveviewFlashComponentsExampleWeb.FirstComponent do
   end
 
   def handle_event("click", _params, socket) do
-    {:noreply, put_flash(socket, :info, "First-level component button clicked!")}
+    {:noreply, put_flash!(socket, :info, "First-level component button clicked!")}
   end
 end

lib/phoenix_liveview_flash_components_example_web/components/second_component.ex

@@ -17,6 +17,6 @@ defmodule PhoenixLiveviewFlashComponentsExampleWeb.SecondComponent do
   end
 
   def handle_event("click", _params, socket) do
-    {:noreply, put_flash(socket, :info, "Second-level component button clicked!")}
+    {:noreply, put_flash!(socket, :info, "Second-level component button clicked!")}
   end
 end

lib/phoenix_liveview_flash_components_example_web/live/flash.ex

@@ -0,0 +1,18 @@
+defmodule PhoenixLiveviewFlashComponentsExampleWeb.Flash do
+  import Phoenix.LiveView
+
+  def on_mount(:default, _params, _session, socket) do
+    {:cont, attach_hook(socket, :flash_receiver, :handle_info, &maybe_receive_flash/2)}
+  end
+
+  defp maybe_receive_flash({:put_flash, type, message}, socket) do
+    {:halt, put_flash(socket, type, message)}
+  end
+
+  defp maybe_receive_flash(_, socket), do: {:cont, socket}
+
+  def put_flash!(socket, type, message) do
+    send(self(), {:put_flash, type, message})
+    socket
+  end
+end