pull2refresh/dist/pull2refresh.js

Pull to refresh library

(function (global, factory) {
	typeof exports === 'object' && typeof module !== 'undefined' ? module.exports = factory() :
	typeof define === 'function' && define.amd ? define(factory) :
	(global.pull2refresh = factory());
}(this, (function () { 'use strict';

var PullToRefresh = /** @class */ (function () {
    function PullToRefresh(options) {
        this.startY = null;
        this.refreshInProgress = false;
        this.options = options;
        this.options.refreshElement.style.display = "block";
        this.maxHeight = this.computeOffsetHeight(options.refreshElement);
        this.initalMarginTop = this.computeMarginTop(this.options.pullableElement);
        if (!this.options.threshold) {
            this.options.threshold = this.maxHeight;
        }
        this.reset();
        this.options.pullableElement.addEventListener("touchstart", this.start.bind(this));
        this.options.pullableElement.addEventListener("mousedown", this.start.bind(this));
        document.addEventListener("touchmove", this.move.bind(this));
        document.addEventListener("mousemove", this.move.bind(this));
        document.addEventListener("touchend", this.end.bind(this));
        document.addEventListener("mouseup", this.end.bind(this));
    }
    PullToRefresh.prototype.done = function () {
        this.refreshInProgress = false;
        this.reset();
    };
    PullToRefresh.prototype.reset = function () {
        this.startY = null;
        this.options.pullableElement.style.marginTop = this.initalMarginTop - this.maxHeight + "px";
    };
    PullToRefresh.prototype.start = function (event) {
        if (!this.isScrollToTop()) {
            // Don't pull to refresh when scroll bar is not at top
            return;
        }
        if (this.refreshInProgress) {
            return;
        }
        this.reset();
        this.startY = this.pageY(event);
    };
    PullToRefresh.prototype.move = function (event) {
        if (this.startY === null || this.refreshInProgress) {
            return;
        }
        var delta = this.pageY(event) - this.startY;
        if (delta <= 0) {
            return;
        }
        // Display the refresh element
        var margin = this.maxHeight - delta;
        if (margin < 0) {
            margin = 0;
        }
        this.options.pullableElement.style.marginTop = -margin + "px";
        // Callback
        if (this.options.onPull && this.options.threshold) {
            var ratio = delta / this.options.threshold;
            this.options.onPull(ratio > 1 ? 1 : ratio);
        }
    };
    PullToRefresh.prototype.end = function (event) {
        if (this.refreshInProgress) {
            return;
        }
        if (this.startY !== null) {
            var delta = this.pageY(event) - this.startY;
            if (this.options.threshold && delta >= this.options.threshold) {
                this.refreshInProgress = true;
                this.options.onRefresh();
                return;
            }
        }
        this.reset();
    };
    PullToRefresh.prototype.pageY = function (event) {
        if (event instanceof MouseEvent) {
            return event.pageY;
        }
        else {
            if (event.touches && event.touches.length) {
                return event.touches[event.touches.length - 1].pageY;
            }
        }
        return 0;
    };
    PullToRefresh.prototype.computeOffsetHeight = function (element) {
        if (element.offsetHeight) {
            return element.offsetHeight;
        }
        var height = window.getComputedStyle(element).height;
        if (!height) {
            return 0;
        }
        var computed = parseInt(height, 10);
        if (isNaN(computed)) {
            return 0;
        }
        return computed;
    };
    PullToRefresh.prototype.computeMarginTop = function (element) {
        var margin = parseInt(window.getComputedStyle(element).getPropertyValue("margin-top"), 10);
        if (isNaN(margin)) {
            return 0;
        }
        return margin;
    };
    PullToRefresh.prototype.isScrollToTop = function () {
        return this.options.pullableElement.getBoundingClientRect().top === this.computeMarginTop(this.options.pullableElement);
    };
    return PullToRefresh;
}());

return PullToRefresh;

})));