Korean keyboard: unwrap InputText on layout change

The korean keyboard wraps InputText and overrides some
of its methods to process input in some specific way.
When switching to another keyboard layout, the original
methods need to be restored.

frontend/ui/data/keyboardlayouts/ko_KR_keyboard.lua

@@ -26,9 +26,21 @@ local wrapInputBox = function(inputbox)
     if inputbox._wrapped == nil then
         inputbox._wrapped = true
 
-        -- helper function
+        -- helper functions
+        local copied_names = {}
+        local function restore_func_references(obj)
+            for __, name in ipairs(copied_names) do
+                local orig_name = "_" .. name
+                if obj[orig_name] then
+                    obj[name] = obj[orig_name]
+                    obj[orig_name] = nil
+                end
+            end
+        end
+
         local function copy_func_reference(obj, name)
             obj["_" .. name] = obj[name]
+            table.insert(copied_names, name)
         end
 
         -- override original implementations with helper object
@@ -82,6 +94,11 @@ local wrapInputBox = function(inputbox)
         wrap_touch_event_func_with_hghelper_reset(inputbox, "onTapTextBox")
         wrap_touch_event_func_with_hghelper_reset(inputbox, "onHoldTextBox")
         wrap_touch_event_func_with_hghelper_reset(inputbox, "onSwipeTextBox")
+
+        return function() -- return unwrap function
+            restore_func_references(inputbox)
+            inputbox._wrapped = nil
+        end
     end
 end
 

frontend/ui/widget/virtualkeyboard.lua

@@ -666,6 +666,10 @@ local VirtualKeyboard = FocusManager:new{
 }
 
 function VirtualKeyboard:init()
+    if self.uwrap_func then
+        self.uwrap_func()
+        self.uwrap_func = nil
+    end
     local lang = self:getKeyboardLayout()
     local keyboard_layout = self.lang_to_keyboard_layout[lang] or self.lang_to_keyboard_layout["en"]
     local keyboard = require("ui/data/keyboardlayouts/" .. keyboard_layout)
@@ -685,7 +689,7 @@ function VirtualKeyboard:init()
         self.key_events.Close = { {"Back"}, doc = "close keyboard" }
     end
     if keyboard.wrapInputBox then
-        keyboard.wrapInputBox(self.inputbox)
+        self.uwrap_func = keyboard.wrapInputBox(self.inputbox) or self.uwrap_func
     end
 end