Switch のようなインターフェースを、あらゆる画面のアプリに

<!-- resources/xml/activity/hello.xml -->
<aurore:AppletFrame>
    <aurore:Box
        title="Hello"
        axis="column"
        alignItems="center"
        justifyContent="center"
        gap="20">

        <aurore:Label
            text="@i18n/hello/welcome"
            fontSize="24" />

        <aurore:Button
            id="hello_button"
            style="primary"
            width="300"
            text="Say hello" />

    </aurore:Box>
</aurore:AppletFrame>

// hello_activity.hpp
#include <aurore.hpp>

class HelloActivity : public aurore::Activity
{
  public:
    CONTENT_FROM_XML_RES("activity/hello.xml");

    void onContentAvailable() override
    {
        button->registerClickAction([](aurore::View*) {
            aurore::Application::notify("Hello!");
            return true;
        });
    }

  private:
    AURORE_BIND(aurore::Button, button, "hello_button");
};