client: Add a property::active signal.

lib/awful/client.lua

@@ -1485,6 +1485,26 @@ end
 --        switch_to_tag = true,
 --    }
 --
+--    -- Get notified when a client gets or loses the focus:
+--    c:connect_signal("property::active", function(c, is_active)
+--        -- do something
+--    end)
+--
+--    -- Get notified when any client gets or loses the focus:
+--    client.connect_signal("property::active", function(c, is_active)
+--        -- do something
+--    end)
+--
+--    -- Get notified when any client gets the focus:
+--    client.connect_signal("focus", function(c)
+--        -- do something
+--    end)
+--
+--    -- Get notified when any client loses the focus:
+--    client.connect_signal("unfocus", function(c)
+--        -- do something
+--    end)
+--
 -- @property active
 -- @tparam boolean active
 -- @see activate

objects/client.c

@@ -1252,6 +1252,9 @@ client_unfocus_internal(client_t *c)
     globalconf.focus.client = NULL;
 
     luaA_object_push(L, c);
+
+    lua_pushboolean(L, false);
+    luaA_object_emit_signal(L, -2, "property::active", 1);
     luaA_object_emit_signal(L, -1, "unfocus", 0);
     lua_pop(L, 1);
 }
@@ -1369,8 +1372,11 @@ client_focus_update(client_t *c)
     luaA_object_push(L, c);
     client_set_urgent(L, -1, false);
 
-    if(focused_new)
+    if(focused_new) {
+        lua_pushboolean(L, true);
+        luaA_object_emit_signal(L, -2, "property::active", 1);
         luaA_object_emit_signal(L, -1, "focus", 0);
+    }
 
     lua_pop(L, 1);