Derive Macro gui_derive::Widget

#[derive(Widget)]
{
    // Attributes available to this derive:
    #[gui]
}

Custom derive functionality for the gui::Widget trait.

Using this macro a default implementation of the gui::Widget trait can be created. Note that this trait is just a unification of the gui::Object, gui::Renderer, and gui::Handleable traits. Note furthermore that only implementations of the former two will be auto generated. The reason for this behavior is that gui::Handleable most likely needs customization to accommodate for custom event handling behavior.

This macro roughly expands to the following code:

impl gui::Renderable for TestWidget {
  fn type_id(&self) -> TypeId {
    TypeId::of::<TestWidget>()
  }
  fn render(&self, renderer: &gui::Renderer, bbox: gui::BBox, cap: &gui::Cap) -> gui::BBox {
    renderer.render(self, bbox, cap)
  }
}

impl gui::Object for TestWidget {
  fn id(&self) -> gui::Id {
    self.id
  }
}

impl gui::Widget<Event> for TestWidget {
  fn type_id(&self) -> TypeId {
    TypeId::of::<TestWidget>()
  }
}