Add partial dynamic overlay support

This will require a better event API to be useful, including issue #10

README.md

@@ -184,6 +184,7 @@ Multiple items can have multiple sets of options.
 | y               | Y position (absolute)                              | number                        |
 | sub_menu_on     | Show submenu on selection or when clicking         | see "event" enum              |
 | select_on       | The event used to trigger item selection           | see "event" enum              |
+| overlay         | A layer on top of the item                         | function(data,item,cr,w,h)    |
 
 ###Item options
 
@@ -211,6 +212,7 @@ Multiple items can have multiple sets of options.
 | button3        | Right mouse button action                    | function          |
 | button4        | Scroll up action                             | function          |
 | button5        | Scroll down action                           | function          |
+| overlay        | See menu.overlay                             | function          |
 
 ###Common methods
 

base.lua

@@ -27,14 +27,17 @@ local module = {
     LEAVE    = 1001,
   },
   item_flags     = {
-    NONE     = 0,
-    SELECTED = 1, -- Single item selected
-    HOVERED  = 2, -- Mouse hover
-    PRESSED  = 3, -- Mouse pressed
-    URGENT   = 4, -- Need attention
-    USED     = 5, -- Common flag
-    DISABLED = 6, -- Cannot be interacted with
-    CHECKED  = 7, -- When checkbox isn't enough
+    NONE      = 0 ,
+    SELECTED  = 1 , -- Single item selected [[FOCUS]]
+    HOVERED   = 2 , -- Mouse hover
+    PRESSED   = 3 , -- Mouse pressed
+    URGENT    = 4 , -- Need attention
+    USED      = 5 , -- Common flag
+    DISABLED  = 6 , -- Cannot be interacted with
+    CHECKED   = 7 , -- When checkbox isn't enough
+    ALTERNATE = 8 ,
+    HIGHLIGHT = 9 ,
+    HEADER    = 10,
 
     -- Implementation defined flags
     USR1     = 101,
@@ -167,7 +170,8 @@ local function add_item(data,args)
       tooltip     = args.tooltip     or nil                                                                 ,
       item_style  = args.item_style  or nil                                                                 ,
       item_layout = args.item_layout or nil                                                                 ,
-      selected    = false,
+      selected    = false                                                                                   ,
+      overlay     = args.overlay     or data.overlay or nil                                                 ,
     },
     force_private = {
       visible = true,
@@ -336,6 +340,7 @@ local function new(args)
       y               = args.y or 0,
       sub_menu_on     = args.sub_menu_on or module.event.SELECTED,
       select_on       = args.select_on or module.event.HOVER,
+      overlay         = args.overlay or nil,
     },
     get_map = {
       is_menu       = function() return true end,

impl/taglist/init.lua

@@ -28,12 +28,14 @@ local state = {
 local cache = setmetatable({}, { __mode = 'k' })
 
 local function create_item(t,s)
-  local item = instances[s]:add_item { text = t.name, icon = tag.geticon(t), button1 = function()
+  local menu = instances[s]
+  if not menu then return end
+  local item = menu:add_item { text = t.name, icon = tag.geticon(t), button1 = function()
     tag.viewonly(t)
   end}
   item._internal.set_map.used = function(value)
-    local item_style = item.item_style or instances[s].item_style
-    item_style(instances[s],item,{value and radical.base.item_flags.USED or nil,item.selected and 1 or nil})
+    local item_style = item.item_style or menu.item_style
+    item_style(menu,item,{value and radical.base.item_flags.USED or nil,item.selected and 1 or nil})
   end
   item._internal.screen = s
   cache[t] = item
@@ -96,6 +98,7 @@ local function init()
       item.icon = tag.geticon(t)
     end
   end)
+  is_init = true
 end
 
 local function new(s)

impl/tasklist/init.lua

@@ -119,7 +119,10 @@ local function new(screen)
     fg       = beautiful.fg_normal,
     bg_focus = beautiful.taglist_bg_image_selected2 or beautiful.bg_focus,
     bg_hover   = beautiful.menu_bg_focus,
-    disable_markup = true
+    disable_markup = true,
+    overlay = function(data,item,cd,w,h)
+      print("foo!")
+    end
   }
 
   -- Clear the menu and repopulate it

item_layout/horizontal.lua

@@ -196,10 +196,17 @@ local function create_item(item,data,args)
 
   -- Set widget
   item.widget = bg
+  bg._item    = item
 
   -- Tooltip
   item.widget:set_tooltip(item.tooltip)
 
+  -- Overlay
+  item._internal.set_map.overlay = function(value)
+    item._private_data.overlay = value
+    item.widget:emit_signal("widget::updated")
+  end
+
   -- Draw
   local item_style = item.item_style or data.item_style
   item_style(data,item,{})

item_style/arrow_single.lua

@@ -28,6 +28,10 @@ local function suffix_draw(self, w, cr, width, height)
   cr:close_path()
   cr:clip()
   wibox.widget.background.draw(self, w, cr, width, height)
+  local overlay = self._item and self._item.overlay
+  if overlay then
+    overlay(self._item._menu,self._item,cr,width,height)
+  end
   cr:restore()
 end