如果我在单独的HTML,CSS和Javascript文件中编写this codes并使用浏览器将其打开,则当在视口(viewport)高度中间观察到目标时,将显示粘性共享栏,而当在视口(viewport)高度底部观察到目标时,将在codepen中显示。是什么原因?
{
class StickyShareBar {
constructor(element) {
this.element = element;
this.contentTarget = document.getElementsByClassName('js-sticky-sharebar-target');
this.showClass = 'sticky-sharebar--on-target';
this.threshold = '50%';
this.initShareBar();
}
initShareBar() {
if(this.contentTarget.length < 1) {
this.element.addClass( this.showClass);
return;
}
if(intersectionObserverSupported) {
this.initObserver();
} else {
this.element.addClass(this.showClass);
}
}
initObserver() {
const self = this;
var observer = new IntersectionObserver(
function(entries, observer) {
self.element.classList.toggle( self.showClass, entries[0].isIntersecting);
},
{
rootMargin: "0px 0px -"+this.threshold+" 0px"}
);
observer.observe(this.contentTarget[0]);
}
}
const stickyShareBar = document.getElementsByClassName('js-sticky-sharebar'),
intersectionObserverSupported = ('IntersectionObserver' in window && 'IntersectionObserverEntry' in window && 'intersectionRatio' in window.IntersectionObserverEntry.prototype);
new StickyShareBar(stickyShareBar[0]);
}
最佳答案
rootMargin
可能是一个问题,而您正在使用iframe
https://w3c.github.io/IntersectionObserver/#dom-intersectionobserver-rootmargin
https://github.com/w3c/IntersectionObserver/issues/372