add mouse controls to brightness widget

brightness-widget/brightness.lua

@@ -10,17 +10,19 @@
 
 local wibox = require("wibox")
 local watch = require("awful.widget.watch")
+local spawn = require("awful.spawn")
 
---local GET_BRIGHTNESS_CMD = "xbacklight -get"
-local GET_BRIGHTNESS_CMD = "light -G"
-local path_to_icons = "/usr/share/icons/Arc/status/symbolic/"
+local PATH_TO_ICON = "/usr/share/icons/Arc/status/symbolic/display-brightness-symbolic.svg"
+local GET_BRIGHTNESS_CMD = "light -G"   -- "xbacklight -get"
+local INC_BRIGHTNESS_CMD = "light -A 1" -- "xbacklight -inc 5"
+local DEC_BRIGHTNESS_CMD = "light -U 1" -- "xbacklight -dec 5"
 
 local brightness_text = wibox.widget.textbox()
 brightness_text:set_font('Play 9')
 
 local brightness_icon = wibox.widget {
     {
-    	image = path_to_icons .. "display-brightness-symbolic.svg",
+    	image = PATH_TO_ICON,
     	resize = false,
         widget = wibox.widget.imagebox,
     },
@@ -34,13 +36,21 @@ local brightness_widget = wibox.widget {
     layout = wibox.layout.fixed.horizontal,
 }
 
-watch(
-    GET_BRIGHTNESS_CMD, 1,
-    function(widget, stdout, stderr, exitreason, exitcode)
-        local brightness_level = tonumber(string.format("%.0f", stdout))
-        widget:set_text(" " .. brightness_level .. "%")
-    end,
-    brightness_text
-)
+local update_widget = function(widget, stdout, stderr, exitreason, exitcode)
+    local brightness_level = tonumber(string.format("%.0f", stdout))
+    widget:set_text(" " .. brightness_level .. "%")
+end,
+
+brightness_widget:connect_signal("button::press", function(_,_,_,button)
+    if (button == 4)     then spawn(INC_BRIGHTNESS_CMD, false)
+    elseif (button == 5) then spawn(DEC_BRIGHTNESS_CMD, false)
+    end
+
+    spawn.easy_async(GET_BRIGHTNESS_CMD, function(stdout, stderr, exitreason, exitcode)
+        update_widget(brightness_widget, stdout, stderr, exitreason, exitcode)
+    end)
+end)
+
+watch(GET_BRIGHTNESS_CMD, 1, update_widget, brightness_text)
 
 return brightness_widget