Box height increases endless if it set to AUTO and one child height is set by percent value.

Remove this code parts:

• unused
• uncommented

Example: /* int IntValue::get::operator()() { //return IntValue; } */

this file is a finished example

Layout recalculation at Box (calcLayoutSize) need multible calls to fish calculation

When you bring panui app to background and foreground multiple times, the screen stops updating.
If you rotate screen the viewport not even changes size:

The description in readme is a bit too short :/
what is the goal of the project ?

If you use the following code, text will not be displayed immediately.
Only after window size changed.

(...)

Text *txt = new Text();
txt->text("Hi");

Ui *window = new Ui(400, 400, "Example");
window->setRootView(txt);

(...)

animate style attributes:

headline->textColor->animate(2 /*seconds*/)->to("#FF0000")
              ->after(headline->textColor->animate(2 /*seconds*/)->to("#00FF00"));

AnimationSet animation();
animation->startWith(headline->textColor->animate(2 /*seconds*/)->to("#FF0000"));
animation->endWith(headline->textColor->animate(2 /*seconds*/)->to("#00FF00"));
animation->repeat();
animation->duration(4 /*seconds*/);
animation->start()

width set to AUTO has no effect