Function zng_wgt::auto_hide

pub fn auto_hide(child: impl UiNode, enabled: impl IntoVar<bool>) -> impl UiNode

P Defines if the widget only renders if it’s bounds intersects with the viewport auto-hide rectangle.

The auto-hide rect is usually (1.vw(), 1.vh()) of extra space around the viewport, so only widgets that transform themselves very far need to set this, disabling auto-hide for a widget does not disable it for descendants.

Examples

The example demonstrates a container that is fixed in the scroll viewport, it sets the x and y properties to always stay in frame. Because the container is layout out of view and just transformed back into view it auto-hides while visible, the example uses auto_hide = false; to fix the issue.

fn center_viewport(msg: impl UiNode) -> impl UiNode {
    Container! {
        layout::x = merge_var!(SCROLL.horizontal_offset(), SCROLL.zoom_scale(), |&h, &s| h.0.fct_l() - 1.vw() / s * h);
        layout::y = merge_var!(SCROLL.vertical_offset(), SCROLL.zoom_scale(), |&v, &s| v.0.fct_l() - 1.vh() / s * v);
        layout::scale = SCROLL.zoom_scale().map(|&fct| 1.fct() / fct);
        layout::transform_origin = 0;
        widget::auto_hide = false;
        layout::max_size = (1.vw(), 1.vh());

        child_align = Align::CENTER;
        child = msg;
    }
}