Touch Screen Scroll Effect
Mang hiệu ứng cuộn cảm ứng vào blog của bạn
Cách thực hiện: Vào Mẫu >> Chỉnh sửa HTML và thêm đoạn code sau trước thẻ </body> <script type='text/javascript'>
//<![CDATA[
function TouchScroll() {
var instance = this;
var Event = {
CHANGE: 'change',
COMPLETE: 'complete',
ERROR: 'error',
TOUCH_START: 'touchstart',
TOUCH_MOVE: 'touchmove',
TOUCH_END: 'touchend',
MOUSE_DOWN: 'mousedown',
MOUSE_MOVE: 'mousemove',
MOUSE_UP: 'mouseup'
};
this.options = {
'element': null
};
var drag = false;
var startevent = {};
var startpercentage = {};
var axis = 'y';
var target;
this.load = function(data) {
for (var item in data) {this.options[item] = data[item];}
addListeners();
setupAnimation();
}
function setupAnimation() {
window.requestAnimFrame = (function() {
return window.requestAnimationFrame ||
window.webkitRequestAnimationFrame ||
window.mozRequestAnimationFrame ||
window.oRequestAnimationFrame ||
window.msRequestAnimationFrame ||
function(callback, element) {window.setTimeout(callback, 1000 / 60);};
})();
}
function addListeners() {
if (instance.options.element.addEventListener) {
instance.options.element.addEventListener(Event.MOUSE_DOWN, onTouchStart, false);
instance.options.element.addEventListener(Event.MOUSE_MOVE, onTouchMove, false);
instance.options.element.addEventListener(Event.MOUSE_UP, onTouchEnd, false);
instance.options.element.addEventListener(Event.TOUCH_START, onTouchStart, false);
instance.options.element.addEventListener(Event.TOUCH_MOVE, onTouchMove, false);
instance.options.element.addEventListener(Event.TOUCH_END, onTouchEnd, false);
}
}
function onTouchStart(e) {
drag = true;
target = instance.options.element || e.target;
startevent = e;
startpercentage = {x: (e.x/window.innerWidth)*100, y: (e.y/window.innerHeight)*100}
//console.log('onTouchStart', e, target);
e.preventDefault();
}
function onTouchMove(e) {
if (drag == true) {
var diffx = (startevent.pageX-e.pageX);
var diffy = (startevent.pageY-e.pageY);
target.scrollLeft += diffx;
target.scrollTop += diffy;
if (Math.abs(diffx) > 60) {axis = 'x';}
else if (Math.abs(diffy) > 100) {axis = 'y';}
//console.log('onTouchMove', target, diffx, diffy);
e.preventDefault();
}
}
function onTouchEnd(e) {
drag = false;
var endpercentage = {x: (e.x/window.innerWidth)*100, y: (e.y/window.innerHeight)*100}
var diffpercentagex = -(endpercentage.x-startpercentage.x);
var diffpercentagey = -(endpercentage.y-startpercentage.y);
var diffx = (window.innerWidth/100)*diffpercentagex;
var diffy = (window.innerHeight/100)*diffpercentagey;
//console.log('onTouchEnd', e, diffpercentagex, diffpercentagey);
//animate();
scrollAxis(diffx*1.5, diffy*1.5, axis);
e.preventDefault();
}
function animate() {
requestAnimFrame(animate);
console.log('animate');
}
function scrollAxis(diffx, diffy, axis) {
var x = target.scrollLeft;
var y = target.scrollTop;
var start = y;
var stop = start+diffy;
if (axis == 'x') {
start = x;
stop = start+diffx;
}
var distance = stop > start ? stop - start : start - stop;
if (distance < 50) {
if (axis == 'x') { instance.updatePosition(stop, y); }
else { instance.updatePosition(x, stop); }
return;
}
var speedY = Math.round(distance);
if (speedY >= 20) speedY = 20;
var step = Math.round(distance / 30);
var leapY = stop > start ? start + step : start - step;
var timer = 0;
//console.log(axis, distance, target, start, stop);
if (stop > start) {
for ( var i=start; i<stop; i+=step ) {
if (axis == 'x') { setTimeout("touchscroll.updatePosition("+leapY+", 0)", timer*speedY); }
else { setTimeout("touchscroll.updatePosition(0, "+leapY+")", timer*speedY); }
leapY += step;
if (leapY > stop) leapY = stop;
timer++;
}
return;
}
for ( var i=start; i>stop; i-=step ) {
if (axis == 'x') { setTimeout("touchscroll.updatePosition("+leapY+", 0)", timer*speedY); }
else { setTimeout("touchscroll.updatePosition(0, "+leapY+")", timer*speedY); }
leapY -= step;
if (leapY < stop) leapY = stop;
timer++;
}
}
this.updatePosition = function(x, y) {
//console.log('window.scrollTo', x, y);
target.scrollLeft = x;
target.scrollTop = y;
}
}
TouchScroll.prototype = new TouchScroll();
var touchscroll = new TouchScroll();
touchscroll.load({
'element': document.getElementsByTagName('body')[0]
});
//]]>
</script>
Bạn thử kéo chuột trái vào khung ví dụ sau nhé
Mẹo nhỏ khi bình luận