is_shown() utility | Bugfix: sub elements instantly updated if :update() is called when they're displayed

DOCS.md

@@ -38,6 +38,7 @@ Install it as any other mod `¯\_(ツ)_/¯`
 * `new({params})`: creates a new panel
 * `show()`: makes the panel appear
 * `hide()`: makes the panel disappear (but it's still assigned to the player)
+* `is_shown()`: whether the panel is currently displayed
 * `remove()`: deletes it
 * `update(panel_params, txt_elems, img_elems)`: updates only the mentioned parameters. For instance, calling  
 

api.lua

@@ -26,7 +26,9 @@ Panel = {
     },
 
     sub_img_elems = {},
-    sub_txt_elems = {}
+    sub_txt_elems = {},
+
+    is_shown = false
 
 }
 
@@ -135,6 +137,7 @@ function Panel:show()
     self.hud_id[name] = player:hud_add(self[name])
   end
 
+  self.is_shown = true
 end
 
 
@@ -149,12 +152,15 @@ function Panel:hide()
     end
 	end
 
+  self.is_shown = false
 end
 
 
 
 function Panel:update(def, txt_elems, img_elems)
 
+  local player = minetest.get_player_by_name(self.player_name)
+
   if def ~= nil then
     for k, v in pairs(def) do
       self[k] = v
@@ -166,6 +172,9 @@ function Panel:update(def, txt_elems, img_elems)
     for elem, _ in pairs(txt_elems) do
       for k, v in pairs(txt_elems[elem]) do
         self[elem][k] = v
+        if self.is_shown then
+          player:hud_change(self.hud_id[elem], k, v)
+        end
       end
     end
 
@@ -176,6 +185,9 @@ function Panel:update(def, txt_elems, img_elems)
     for elem, _ in pairs(img_elems) do
       for k, v in pairs(img_elems[elem]) do
         self[elem][k] = v
+        if self.is_shown then
+          player:hud_change(self.hud_id[elem], k, v)
+        end
       end
     end
 
@@ -192,6 +204,15 @@ end
 
 
 
+function Panel:is_shown()
+  if self.is_shown then return true
+  else return false end
+end
+
+
+
+
+
 ----------------------------------------------
 -----------------GETTERS----------------------
 ----------------------------------------------
@@ -202,6 +223,8 @@ end
 
 
 
+
+
 ----------------------------------------------
 ---------------FUNZIONI LOCALI----------------
 ----------------------------------------------

panel.example

@@ -1,4 +1,5 @@
 {
+    name = "mymod_mypanel",
 	player = "singleplayer",
 	position = { x = 1, y = 0.5 },
 	alignment = { x = -1, y = 0 },