Touchmover Mobile Phone End Drag method

function drag (obj, parentnode) {
var obj = document.getElementById (obj);
if (arguments.length = = 1) {
var parentnode = window.self;
var pWidth = parentnode.innerwidth, pheight = parentnode.innerheight;
} else {
var parentnode = document.getElementById (parentnode);
var pWidth = parentnode.clientwidth, pheight = parentnode.clientheight;
}
Obj.addeventlistener (' Touchstart ', function (event) {
When there is only one finger.
if (event.touches.length = = 1) {
Prohibit browser default thing
Event.preventdefault ();
};
var touch = event.targettouches[0];
var disx = touch.clientx-obj.offsetleft, Disy = touch.clienty-obj.offsettop;
var owidth = obj.offsetwidth, oheight = obj.offsetheight;
Obj.addeventlistener (' Touchmove ', function (event) {
var touch = event.targettouches[0];
Obj.style.left = touch.clientx-disx + ' px ';
Obj.style.top = Touch.clienty-disy + ' px ';
Left
Console.log (Obj.offsetleft)
if (obj.offsetleft-40 <= 0) {
Obj.style.left = 0;
};
Right
if (obj.offsetleft >= pwidth-owidth) {
Obj.style.left = pwidth-owidth + ' px ';
};
Above
if (obj.offsettop <= 0) {
obj.style.top = 0;
};
Below
if (obj.offsettop >= pheight-oheight) {
Obj.style.top = pheight-oheight + ' px ';
};
});
Obj.addeventlistener (' Touchend ', function (event) {
Obj.removeeventlistener (' Touchmove ');
Obj.removeeventlistener (' touchend ');
})
});
}

Touchmover Mobile Phone End Drag method