ExTermbox v0.3.2 ExTermbox.EventManager View Source

This module implements an event manager that notifies subscribers of the keyboard, mouse and resize events received from the termbox API.

It works by running a poll loop that calls out to the NIFs in ExTermbox.Bindings:

The ExTermbox.Bindings.poll_event/1 NIF is called with the event manager's pid.
The NIF creates a new thread for the blocking poll routine and immediately returns with a resource representing a handle for the thread.
The thread blocks until an event is received (e.g., a keypress), at which point it sends a message to the event manager with the event data and exits.
The event manager notifies its subscribers of the event and returns to step 1.

Example Usage:

def event_loop do
  receive do
    {:event, %Event{ch: ?q} = event} ->
      Bindings.shutdown()
    {:event, %Event{} = event} ->
      # handle the event and wait for another...
      event_loop()
  end
end

{:ok, pid} = EventManager.start_link()
:ok = EventManager.subscribe(self())
event_loop()

Link to this section Summary

Functions

child_spec(init_arg)

Returns a specification to start this module under a supervisor

init(atom)

Invoked when the server is started. start_link/3 or start/3 will block until it returns

start_link()

subscribe(subscriber_pid)

Subscribes the given pid to future event notifications

Link to this section Functions

child_spec(init_arg) View Source

Returns a specification to start this module under a supervisor.

See Supervisor.

init(atom) View Source

Invoked when the server is started. start_link/3 or start/3 will block until it returns.

init_arg is the argument term (second argument) passed to start_link/3.

Returning {:ok, state} will cause start_link/3 to return {:ok, pid} and the process to enter its loop.

Returning {:ok, state, timeout} is similar to {:ok, state} except handle_info(:timeout, state) will be called after timeout milliseconds if no messages are received within the timeout.

Returning {:ok, state, :hibernate} is similar to {:ok, state} except the process is hibernated before entering the loop. See c:handle_call/3 for more information on hibernation.

Returning {:ok, state, {:continue, continue}} is similar to {:ok, state} except that immediately after entering the loop the c:handle_continue/2 callback will be invoked with the value continue as first argument.

Returning :ignore will cause start_link/3 to return :ignore and the process will exit normally without entering the loop or calling c:terminate/2. If used when part of a supervision tree the parent supervisor will not fail to start nor immediately try to restart the GenServer. The remainder of the supervision tree will be started and so the GenServer should not be required by other processes. It can be started later with Supervisor.restart_child/2 as the child specification is saved in the parent supervisor. The main use cases for this are:

The GenServer is disabled by configuration but might be enabled later.
An error occurred and it will be handled by a different mechanism than the Supervisor. Likely this approach involves calling Supervisor.restart_child/2 after a delay to attempt a restart.

Returning {:stop, reason} will cause start_link/3 to return {:error, reason} and the process to exit with reason reason without entering the loop or calling c:terminate/2.

Callback implementation for GenServer.init/1.

ExTermbox

v0.3.2