[patch] textbox.v needs a trivial fix for touch devices

[xandro0777]

On touch devices it does not subscribe touch events like touch _down that is needed to focus the textbox and move cursor for example.

Patch bellow fixes it.

--- textbox.v   2021-09-17 23:41:40.015377118 +0200
+++ /home/rz/.vmodules/ui/textbox.v     2021-09-23 00:25:17.860375560 +0200
@@ -212,8 +212,10 @@
        subscriber.subscribe_method(events.on_char, tb_char, tb)
        // subscriber.subscribe_method(events.on_key_up, tb_key_up, tb)
        subscriber.subscribe_method(events.on_mouse_down, tb_mouse_down, tb)
+       subscriber.subscribe_method(events.on_touch_down, tb_mouse_down, tb)
        subscriber.subscribe_method(events.on_mouse_move, tb_mouse_move, tb)
        subscriber.subscribe_method(events.on_mouse_up, tb_mouse_up, tb)
+       subscriber.subscribe_method(events.on_touch_up, tb_mouse_up, tb)
 }
 
 [manualfree]

[xandro0777]

Submitted https://github.com/vlang/ui/pull/395