egirlskey/packages/frontend/src/directives/appear.ts
2022-12-27 14:36:33 +09:00

22 lines
430 B
TypeScript

import { Directive } from 'vue';
export default {
mounted(src, binding, vn) {
const fn = binding.value;
if (fn == null) return;
const observer = new IntersectionObserver(entries => {
if (entries.some(entry => entry.isIntersecting)) {
fn();
}
});
observer.observe(src);
src._observer_ = observer;
},
unmounted(src, binding, vn) {
if (src._observer_) src._observer_.disconnect();
},
} as Directive;