react-virtualized
Version:
React components for efficiently rendering large, scrollable lists and tabular data
192 lines (188 loc) • 8.26 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", {
value: true
});
exports["default"] = createDetectElementResize;
/**
* Detect Element Resize.
* https://github.com/sdecima/javascript-detect-element-resize
* Sebastian Decima
*
* Forked from version 0.5.3; includes the following modifications:
* 1) Guard against unsafe 'window' and 'document' references (to support SSR).
* 2) Defer initialization code via a top-level function wrapper (to support SSR).
* 3) Avoid unnecessary reflows by not measuring size for scroll events bubbling from children.
* 4) Add nonce for style element.
* 5) Added support for injecting custom window object
**/
function createDetectElementResize(nonce, hostWindow) {
// Check `document` and `window` in case of server-side rendering
var _window;
if (typeof hostWindow !== 'undefined') {
_window = hostWindow;
} else if (typeof window !== 'undefined') {
_window = window;
} else if (typeof self !== 'undefined') {
_window = self;
} else {
_window = global;
}
var attachEvent = typeof _window.document !== 'undefined' && _window.document.attachEvent;
if (!attachEvent) {
var requestFrame = function () {
var raf = _window.requestAnimationFrame || _window.mozRequestAnimationFrame || _window.webkitRequestAnimationFrame || function (fn) {
return _window.setTimeout(fn, 20);
};
return function (fn) {
return raf(fn);
};
}();
var cancelFrame = function () {
var cancel = _window.cancelAnimationFrame || _window.mozCancelAnimationFrame || _window.webkitCancelAnimationFrame || _window.clearTimeout;
return function (id) {
return cancel(id);
};
}();
var resetTriggers = function resetTriggers(element) {
var triggers = element.__resizeTriggers__,
expand = triggers.firstElementChild,
contract = triggers.lastElementChild,
expandChild = expand.firstElementChild;
contract.scrollLeft = contract.scrollWidth;
contract.scrollTop = contract.scrollHeight;
expandChild.style.width = expand.offsetWidth + 1 + 'px';
expandChild.style.height = expand.offsetHeight + 1 + 'px';
expand.scrollLeft = expand.scrollWidth;
expand.scrollTop = expand.scrollHeight;
};
var checkTriggers = function checkTriggers(element) {
return element.offsetWidth != element.__resizeLast__.width || element.offsetHeight != element.__resizeLast__.height;
};
var scrollListener = function scrollListener(e) {
// Don't measure (which forces) reflow for scrolls that happen inside of children!
if (e.target.className && typeof e.target.className.indexOf === 'function' && e.target.className.indexOf('contract-trigger') < 0 && e.target.className.indexOf('expand-trigger') < 0) {
return;
}
var element = this;
resetTriggers(this);
if (this.__resizeRAF__) {
cancelFrame(this.__resizeRAF__);
}
this.__resizeRAF__ = requestFrame(function () {
if (checkTriggers(element)) {
element.__resizeLast__.width = element.offsetWidth;
element.__resizeLast__.height = element.offsetHeight;
element.__resizeListeners__.forEach(function (fn) {
fn.call(element, e);
});
}
});
};
/* Detect CSS Animations support to detect element display/re-attach */
var animation = false,
keyframeprefix = '',
animationstartevent = 'animationstart',
domPrefixes = 'Webkit Moz O ms'.split(' '),
startEvents = 'webkitAnimationStart animationstart oAnimationStart MSAnimationStart'.split(' '),
pfx = '';
{
var elm = _window.document.createElement('fakeelement');
if (elm.style.animationName !== undefined) {
animation = true;
}
if (animation === false) {
for (var i = 0; i < domPrefixes.length; i++) {
if (elm.style[domPrefixes[i] + 'AnimationName'] !== undefined) {
pfx = domPrefixes[i];
keyframeprefix = '-' + pfx.toLowerCase() + '-';
animationstartevent = startEvents[i];
animation = true;
break;
}
}
}
}
var animationName = 'resizeanim';
var animationKeyframes = '@' + keyframeprefix + 'keyframes ' + animationName + ' { from { opacity: 0; } to { opacity: 0; } } ';
var animationStyle = keyframeprefix + 'animation: 1ms ' + animationName + '; ';
}
var createStyles = function createStyles(doc) {
if (!doc.getElementById('detectElementResize')) {
//opacity:0 works around a chrome bug https://code.google.com/p/chromium/issues/detail?id=286360
var css = (animationKeyframes ? animationKeyframes : '') + '.resize-triggers { ' + (animationStyle ? animationStyle : '') + 'visibility: hidden; opacity: 0; } ' + '.resize-triggers, .resize-triggers > div, .contract-trigger:before { content: " "; display: block; position: absolute; top: 0; left: 0; height: 100%; width: 100%; overflow: hidden; z-index: -1; } .resize-triggers > div { background: #eee; overflow: auto; } .contract-trigger:before { width: 200%; height: 200%; }',
head = doc.head || doc.getElementsByTagName('head')[0],
style = doc.createElement('style');
style.id = 'detectElementResize';
style.type = 'text/css';
if (nonce != null) {
style.setAttribute('nonce', nonce);
}
if (style.styleSheet) {
style.styleSheet.cssText = css;
} else {
style.appendChild(doc.createTextNode(css));
}
head.appendChild(style);
}
};
var addResizeListener = function addResizeListener(element, fn) {
if (attachEvent) {
element.attachEvent('onresize', fn);
} else {
if (!element.__resizeTriggers__) {
var doc = element.ownerDocument;
var elementStyle = _window.getComputedStyle(element);
if (elementStyle && elementStyle.position == 'static') {
element.style.position = 'relative';
}
createStyles(doc);
element.__resizeLast__ = {};
element.__resizeListeners__ = [];
(element.__resizeTriggers__ = doc.createElement('div')).className = 'resize-triggers';
var expandTrigger = doc.createElement('div');
expandTrigger.className = 'expand-trigger';
expandTrigger.appendChild(doc.createElement('div'));
var contractTrigger = doc.createElement('div');
contractTrigger.className = 'contract-trigger';
element.__resizeTriggers__.appendChild(expandTrigger);
element.__resizeTriggers__.appendChild(contractTrigger);
element.appendChild(element.__resizeTriggers__);
resetTriggers(element);
element.addEventListener('scroll', scrollListener, true);
/* Listen for a css animation to detect element display/re-attach */
if (animationstartevent) {
element.__resizeTriggers__.__animationListener__ = function animationListener(e) {
if (e.animationName == animationName) {
resetTriggers(element);
}
};
element.__resizeTriggers__.addEventListener(animationstartevent, element.__resizeTriggers__.__animationListener__);
}
}
element.__resizeListeners__.push(fn);
}
};
var removeResizeListener = function removeResizeListener(element, fn) {
if (attachEvent) {
element.detachEvent('onresize', fn);
} else {
element.__resizeListeners__.splice(element.__resizeListeners__.indexOf(fn), 1);
if (!element.__resizeListeners__.length) {
element.removeEventListener('scroll', scrollListener, true);
if (element.__resizeTriggers__.__animationListener__) {
element.__resizeTriggers__.removeEventListener(animationstartevent, element.__resizeTriggers__.__animationListener__);
element.__resizeTriggers__.__animationListener__ = null;
}
try {
element.__resizeTriggers__ = !element.removeChild(element.__resizeTriggers__);
} catch (e) {
// Preact compat; see developit/preact-compat/issues/228
}
}
}
};
return {
addResizeListener: addResizeListener,
removeResizeListener: removeResizeListener
};
}