Question

我正在尝试在滚动时执行某些功能。基本上，如果满足某个滚动位置，我希望应用程序做一些事情。

这里有一些代码：

  ionViewDidLoad() {
    this.content.ionScroll.subscribe((event) => {
      this.scrollPosition = event.scrollTop;
      if(this.scrollPosition >= 100){
        console.log("more than 100");
      }
      else {
        console.log("less than 100");
      }
    });
  }

它在Web浏览器或Android设备上按预期工作，它在滚动条件下重复运行“console.log（）”。在iOS上，它等待滚动停止，然后它执行console.log（）。我正在阅读在iOS上，由于性能原因，javascript会在滚动时停止。有解决方法吗？

Answer 1

Safari doesnt fire a scroll event until after the scroll is complete, so you'd have to do some custom event listening in this case.

Check out this post: javascript scroll event for iPhone/iPad?

It could be achieved like so:

document.addEventListener("touchmove", ScrollStart, false);
document.addEventListener("scroll", Scroll, false);

function ScrollStart() {
    //start of scroll event for iOS
}

function Scroll() {
    //end of scroll event for iOS
    //and
    //start/end of scroll event for other browsers
}

I would recommend creating a directive, using HostListener to listen for those two events.

Ionic 2：在iOS上滚动时运行功能

1 个答案: