Dala.Socket (dala v0.0.1)

The socket struct passed through all Dala.Screen and Dala.Component callbacks.

Holds two things:

assigns — the public data map your render/1 function reads from @assigns
__dala__ — internal Dala metadata (screen module, platform, view refs, nav stack)

You interact with a socket via assign/2 and assign/3. Never mutate __dala__ directly — it is an internal contract.

Summary

Types

platform()

t()

Functions

assign(socket, kw)

Assign multiple key/value pairs at once from a keyword list or map.

assign(socket, key, value)

Assign a single key/value pair into the socket's assigns.

changed?(socket, key)

Check if any of the given keys have changed since last render.

new(screen, opts \\ [])

Create a new socket for the given screen module.

pop_screen(socket)

Pop the current screen, returning to the previous one.

pop_to(socket, dest)

Pop the stack until the screen registered under dest is at the top.

pop_to_root(socket)

Pop to the root of the current navigation stack.

push_screen(socket, dest, params \\ %{})

Push a new screen onto the navigation stack.

put_root_view(socket, ref)

Store the root view ref returned by the renderer into __dala__.root_view. Called internally after the initial render.

reset_to(socket, dest, params \\ %{})

Replace the entire navigation stack with a single new screen.

switch_tab(socket, tab)

Switch to the named tab in a tab_bar or drawer layout.

Types

platform()

@type platform() :: :android | :ios

t()

@type t() :: %Dala.Socket{
  __dala__: %{
    screen: module() | nil,
    platform: platform(),
    root_view: term(),
    view_tree: map(),
    nav_stack: list(),
    nav_action: term()
  },
  assigns: map()
}

Functions

assign(socket, kw)

@spec assign(t(), keyword() | map()) :: t()

Assign multiple key/value pairs at once from a keyword list or map.

socket = assign(socket, count: 0, name: "test")
socket = assign(socket, %{count: 0})

assign(socket, key, value)

@spec assign(t(), atom(), term()) :: t()

Assign a single key/value pair into the socket's assigns.

socket = assign(socket, :count, 0)

changed?(socket, key)

@spec changed?(t(), atom() | [atom()]) :: boolean()

Check if any of the given keys have changed since last render.

if Socket.changed?(socket, [:count, :name]) do
  # Re-render needed
end

new(screen, opts \\ [])

@spec new(
  module(),
  keyword()
) :: t()

Create a new socket for the given screen module.

Options:

:platform — :android (default) or :ios

pop_screen(socket)

@spec pop_screen(t()) :: t()

Pop the current screen, returning to the previous one.

No-op if already at the root of the stack.

pop_to(socket, dest)

@spec pop_to(t(), atom() | module()) :: t()

Pop the stack until the screen registered under dest is at the top.

dest is a registered atom name or module. No-op if not found in history.

pop_to_root(socket)

@spec pop_to_root(t()) :: t()

Pop to the root of the current navigation stack.

push_screen(socket, dest, params \\ %{})

@spec push_screen(t(), atom() | module(), map()) :: t()

Push a new screen onto the navigation stack.

dest is either a registered atom name (e.g. :counter) or a screen module (e.g. dalaDemo.CounterScreen). params are passed to the new screen's mount/3 as the first argument.

The push is applied after the current callback returns — do_render in Dala.Screen detects the nav_action and mounts the new module.

put_root_view(socket, ref)

@spec put_root_view(t(), term()) :: t()

Store the root view ref returned by the renderer into __dala__.root_view. Called internally after the initial render.

reset_to(socket, dest, params \\ %{})

@spec reset_to(t(), atom() | module(), map()) :: t()

Replace the entire navigation stack with a single new screen.

Used for auth transitions (post-login → home with no back button to login).

switch_tab(socket, tab)

@spec switch_tab(t(), atom()) :: t()

Switch to the named tab in a tab_bar or drawer layout.