VirtualKeyboard: Allow hiding the keyboard with a hold on the down arrow key (#7751)

(And showing it again with a tap on an input field)

frontend/ui/widget/inputtext.lua

@@ -61,6 +61,7 @@ local InputText = InputContainer:new{
     for_measurement_only = nil, -- When the widget is a one-off used to compute text height
     do_select = false, -- to start text selection
     selection_start_pos = nil, -- selection start position
+    is_keyboard_hidden = false, -- to be able to show the keyboard again when it was hidden (by VK itself)
 }
 
 -- only use PhysicalKeyboard if the device does not have touch screen
@@ -121,6 +122,11 @@ if Device:isTouchDevice() or Device:hasDPad() then
         function InputText:onTapTextBox(arg, ges)
             if self.parent.onSwitchFocus then
                 self.parent:onSwitchFocus(self)
+            else
+                if self.is_keyboard_hidden == true then
+                    self:onShowKeyboard()
+                    self.is_keyboard_hidden = false
+                end
             end
             if #self.charlist > 0 then -- Avoid cursor moving within a hint.
                 local textwidget_offset = self.margin + self.bordersize + self.padding
@@ -563,12 +569,21 @@ end
 
 function InputText:onShowKeyboard(ignore_first_hold_release)
     Device:startTextInput()
-
     self.keyboard.ignore_first_hold_release = ignore_first_hold_release
     UIManager:show(self.keyboard)
     return true
 end
 
+function InputText:onHideKeyboard()
+    if not self.has_nav_bar then
+        UIManager:close(self.keyboard)
+        Device:stopTextInput()
+        self.is_keyboard_hidden = true
+    end
+
+    return self.is_keyboard_hiddenend
+end
+
 function InputText:onCloseKeyboard()
     UIManager:close(self.keyboard)
     Device:stopTextInput()