Option to make password visible when entering (#3040)

* Option to make password visible when entering

frontend/ui/widget/inputdialog.lua

@@ -63,6 +63,7 @@ local VerticalGroup = require("ui/widget/verticalgroup")
 local WidgetContainer = require("ui/widget/container/widgetcontainer")
 local UIManager = require("ui/uimanager")
 local Screen = require("device").screen
+local _ = require("gettext")
 
 local InputDialog = InputContainer:new{
     title = "",
@@ -72,6 +73,7 @@ local InputDialog = InputContainer:new{
     buttons = nil,
     input_type = nil,
     enter_callback = nil,
+    show_password_toggle = true,
 
     width = nil,
 
@@ -147,7 +149,26 @@ function InputDialog:init()
         scroll = false,
         parent = self,
     }
-
+    local is_password_type = false
+    if self._input_widget.text_type == "password" then
+        is_password_type = true
+    end
+    if self.show_password_toggle and is_password_type then
+        local button_switch = {
+            {
+                text = _("Show password"),
+                callback = function()
+                    if self._input_widget.text_type == "text" then
+                        self._input_widget.text_type = "password"
+                    else
+                        self._input_widget.text_type = "text"
+                    end
+                    self._input_widget:setText(self._input_widget:getText())
+                end,
+            },
+        }
+        table.insert(self.buttons[1], button_switch[1])
+    end
     self.button_table = ButtonTable:new{
         width = self.width,
         button_font_face = "cfont",