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stickyscroll.js
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stickyscroll.js
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import jQuery from "jquery";
(function($) {
$.fn.unsticky = function() {
return this.trigger("unstick.sticky").unbind(".sticky");
};
$.fn.sticky = function() {
var self = this;
var stuckToBottom = true;
var lastStick = 0;
var keepToBottom = function() {
if (stuckToBottom) {
self.scrollBottom();
}
};
$(window).on("resize.sticky", keepToBottom);
self
.on("unstick.sticky", function() {
$(window).off("resize.sticky", keepToBottom);
})
.on("scroll.sticky", function() {
// When resizing, sometimes the browser sends a bunch of extra scroll events due to content
// reflow, so if we resized within 250ms we can assume it's one of those. The order of said
// events is not predictable, and scroll can happen last, so not setting stuckToBottom is
// not enough, we have to force the scroll still.
if (stuckToBottom && Date.now() - lastStick < 250) {
self.scrollBottom();
} else {
stuckToBottom = self.isScrollBottom();
}
})
.on("scrollBottom.sticky", function() {
stuckToBottom = true;
lastStick = Date.now();
this.scrollTop = this.scrollHeight;
})
.on("msg.sticky", keepToBottom)
.scrollBottom();
return self;
};
$.fn.scrollBottom = function() {
this.trigger("scrollBottom.sticky");
return this;
};
$.fn.isScrollBottom = function() {
var el = this[0];
return el.scrollHeight - el.scrollTop - el.offsetHeight <= 30;
};
})(jQuery);