awesome/lib/gears/timer.lua
Holger Schurig bf2c1993db doc: fix signals (#1455)
- rule reordering was mentioned twice in the NEWS
- fix all shown luadoc errors
- add missing descriptions for signals in module "awesome"
2017-01-28 15:03:56 +01:00

246 lines
7.5 KiB
Lua

---------------------------------------------------------------------------
--- Timer objects and functions.
--
-- @usage
-- -- Create a widget and update its content using the output of a shell
-- -- command every 10 seconds:
-- local mybatterybar = wibox.widget {
-- {
-- min_value = 0,
-- max_value = 100,
-- value = 0,
-- paddings = 1,
-- border_width = 1,
-- forced_width = 50,
-- border_color = "#0000ff",
-- id = "mypb",
-- widget = wibox.widget.progressbar,
-- },
-- {
-- id = "mytb",
-- text = "100%",
-- widget = wibox.widget.textbox,
-- },
-- layout = wibox.layout.stack,
-- set_battery = function(self, val)
-- self.mytb.text = tonumber(val).."%"
-- self.mypb.value = tonumber(val)
-- end,
-- }
--
-- gears.timer {
-- timeout = 10,
-- autostart = true,
-- callback = function()
-- -- You should read it from `/sys/class/power_supply/` (on Linux)
-- -- instead of spawning a shell. This is only an example.
-- awful.spawn.easy_async(
-- {"sh", "-c", "acpi | sed -n 's/^.*, \([0-9]*\)%/\1/p'"},
-- function(out)
-- mybatterybar.battery = out
-- end
-- )
-- end
-- }
--
-- @author Uli Schlachter
-- @copyright 2014 Uli Schlachter
-- @classmod gears.timer
---------------------------------------------------------------------------
local capi = { awesome = awesome }
local ipairs = ipairs
local pairs = pairs
local setmetatable = setmetatable
local table = table
local tonumber = tonumber
local traceback = debug.traceback
local unpack = unpack or table.unpack -- luacheck: globals unpack (compatibility with Lua 5.1)
local glib = require("lgi").GLib
local object = require("gears.object")
local protected_call = require("gears.protected_call")
--- Timer objects. This type of object is useful when triggering events repeatedly.
-- The timer will emit the "timeout" signal every N seconds, N being the timeout
-- value. Note that a started timer will not be garbage collected. Call `:stop`
-- to enable garbage collection.
-- @tfield number timeout Interval in seconds to emit the timeout signal.
-- Can be any value, including floating point ones (e.g. 1.5 seconds).
-- @tfield boolean started Read-only boolean field indicating if the timer has been
-- started.
-- @table timer
--- When the timer is started.
-- @signal .start
--- When the timer is stopped.
-- @signal .stop
--- When the timer had a timeout event.
-- @signal .timeout
local timer = { mt = {} }
--- Start the timer.
function timer:start()
if self.data.source_id ~= nil then
print(traceback("timer already started"))
return
end
self.data.source_id = glib.timeout_add(glib.PRIORITY_DEFAULT, self.data.timeout * 1000, function()
protected_call(self.emit_signal, self, "timeout")
return true
end)
self:emit_signal("start")
end
--- Stop the timer.
function timer:stop()
if self.data.source_id == nil then
print(traceback("timer not started"))
return
end
glib.source_remove(self.data.source_id)
self.data.source_id = nil
self:emit_signal("stop")
end
--- Restart the timer.
-- This is equivalent to stopping the timer if it is running and then starting
-- it.
function timer:again()
if self.data.source_id ~= nil then
self:stop()
end
self:start()
end
--- The timer is started.
-- @property started
-- @param boolean
--- The timer timeout value.
-- **Signal:** property::timeout
-- @property timeout
-- @param number
local timer_instance_mt = {
__index = function(self, property)
if property == "timeout" then
return self.data.timeout
elseif property == "started" then
return self.data.source_id ~= nil
end
return timer[property]
end,
__newindex = function(self, property, value)
if property == "timeout" then
self.data.timeout = tonumber(value)
self:emit_signal("property::timeout")
end
end
}
--- Create a new timer object.
-- @tparam table args Arguments.
-- @tparam number args.timeout Timeout in seconds (e.g. 1.5).
-- @tparam[opt=false] boolean args.autostart Automatically start the timer.
-- @tparam[opt=nil] function args.callback Callback function to connect to the
-- "timeout" signal.
-- @tparam[opt=false] boolean args.single_shot Run only once then stop.
-- @treturn timer
-- @function gears.timer
function timer.new(args)
args = args or {}
local ret = object()
ret.data = { timeout = 0 }
setmetatable(ret, timer_instance_mt)
for k, v in pairs(args) do
ret[k] = v
end
if args.autostart then
ret:start()
end
if args.callback then
ret:connect_signal("timeout", args.callback)
end
if args.single_shot then
ret:connect_signal("timeout", function() ret:stop() end)
end
return ret
end
--- Create a timeout for calling some callback function.
-- When the callback function returns true, it will be called again after the
-- same timeout. If false is returned, no more calls will be done. If the
-- callback function causes an error, no more calls are done.
-- @tparam number timeout Timeout in seconds (e.g. 1.5).
-- @tparam function callback Function to run.
-- @treturn timer The timer object that was set up.
-- @function gears.timer.start_new
-- @see gears.timer.weak_start_new
function timer.start_new(timeout, callback)
local t = timer.new({ timeout = timeout })
t:connect_signal("timeout", function()
local cont = protected_call(callback)
if not cont then
t:stop()
end
end)
t:start()
return t
end
--- Create a timeout for calling some callback function.
-- This function is almost identical to `gears.timer.start_new`. The only difference
-- is that this does not prevent the callback function from being garbage
-- collected. After the callback function was collected, the timer returned
-- will automatically be stopped.
-- @tparam number timeout Timeout in seconds (e.g. 1.5).
-- @tparam function callback Function to start.
-- @treturn timer The timer object that was set up.
-- @function gears.timer.weak_start_new
-- @see gears.timer.start_new
function timer.weak_start_new(timeout, callback)
local indirection = setmetatable({}, { __mode = "v" })
indirection.callback = callback
return timer.start_new(timeout, function()
local cb = indirection.callback
if cb then
return cb()
end
end)
end
local delayed_calls = {}
capi.awesome.connect_signal("refresh", function()
for _, callback in ipairs(delayed_calls) do
protected_call(unpack(callback))
end
delayed_calls = {}
end)
--- Call the given function at the end of the current main loop iteration
-- @tparam function callback The function that should be called
-- @param ... Arguments to the callback function
-- @function gears.timer.delayed_call
function timer.delayed_call(callback, ...)
assert(type(callback) == "function", "callback must be a function, got: " .. type(callback))
table.insert(delayed_calls, { callback, ... })
end
function timer.mt.__call(_, ...)
return timer.new(...)
end
return setmetatable(timer, timer.mt)
-- vim: filetype=lua:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:textwidth=80