Function render_retain 

pub fn render_retain(
    child: impl IntoUiNode,
    retain: impl IntoVar<bool>,
) -> UiNode

P If the render task is kept alive after a frame is produced, this is false by default meaning the image only renders once, if set to true the image will automatically update when the render widget requests a new frame.

This property sets and binds retain to IMAGE_RENDER.retain.