jQuery / JavaScript冲突检测

#1 楼

 var overlaps = (function () {
    function getPositions( elem ) {
        var pos, width, height;
        pos = $( elem ).position();
        width = $( elem ).width();
        height = $( elem ).height();
        return [ [ pos.left, pos.left + width ], [ pos.top, pos.top + height ] ];
    }

    function comparePositions( p1, p2 ) {
        var r1, r2;
        r1 = p1[0] < p2[0] ? p1 : p2;
        r2 = p1[0] < p2[0] ? p2 : p1;
        return r1[1] > r2[0] || r1[0] === r2[0];
    }

    return function ( a, b ) {
        var pos1 = getPositions( a ),
            pos2 = getPositions( b );
        return comparePositions( pos1[0], pos2[0] ) && comparePositions( pos1[1], pos2[1] );
    };
})();

$(function () {
    var area = $( '#area' )[0],
        box = $( '#box0' )[0],
        html;
    
    html = $( area ).children().not( box ).map( function ( i ) {
        return '<p>Red box + Box ' + ( i + 1 ) + ' = ' + overlaps( box, this ) + '</p>';
    }).get().join( '' );

    $( 'body' ).append( html );
}); 

 body {
    padding: 30px;
    color: #444;
    font-family: Arial, sans-serif;
}

h1 {
    font-size: 24px;
    margin-bottom: 20px;
}

#area {
    border: 2px solid gray;
    width: 500px;
    height: 400px;
    position: relative;
}

#area > div {
    background-color: rgba(122, 122, 122, 0.3);
    position: absolute;
    text-align: center;
    font-size: 50px;
    width: 60px;
    height: 60px;
}

#box0 {
    background-color: rgba(255, 0, 0, 0.5) !important;
    top: 150px;
    left: 150px;
}

#box1 {
    top: 260px;
    left: 50px;
}

#box2 {
    top: 110px;
    left: 160px;
}

#box3 {
    top: 200px;
    left: 200px;
}

#box4 {
    top: 50px;
    left: 400px;
}

p {
    margin: 5px 0;
} 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>
<h1>Detect overlapping with JavaScript</h1>
<div id="area">
    <div id="box0"></div>
    <div id="box1">1</div>
    <div id="box2">2</div>
    <div id="box3">3</div>
    <div id="box4">4</div>
</div> 

function detectOverlapping() {
    // code that detects if the box overlaps with a moving box
    setInterval(detectOverlapping, 25);
}

detectOverlapping();  

#2 楼

setInterval(function(){
            //First step would be to get the offset of item 1 and item 2
            //Second would be to get the width of each
            //Third would be to check if the offset+width ever overlaps
                //the offset+width of the 2nd
            //Fourth would be, if so, do X or set a class...
        },10);

#3 楼

$([div1, div2]).droppable(CONFIG_COLLISSION_PREVENTION_DROPPABLE);

var originatingOffset = null;
CONFIG_COLLISSION_PREVENTION_DROPPABLE = {
    tolerance: "touch",
    activate : function (event, ui) {
        // note the initial position/offset when drag starts
        // will be usedful in drop handler to check if the move
        // occurred and in cae overlap occurred, restore the original positions.
        originatingOffset = ui.offset;
    },
    drop : function (event, ui) {
            // If this callback gets invoked, the overlap has occurred. 
            // Use this method to either generate a custom event etc.

            // Here, i used it to nullify the move and resetting the dragged element's 
            // position back to it's original position/offset
            // (which was captured in the 'activate' handler)
        $(ui.draggable).animate({
            top: originatingOffset.top + "px",
            left: originatingOffset.left + "px"
        }, 300);
     }
}

var CLASS_INVALID = "invalid";
// .invalid { border: 1px solid red; }
...
$.extend(CONFIG_COLLISSION_PREVENTION_DROPPABLE, {
   over : function (event, ui) {
        // When an element is over another, it gets detected here;
        // while it may still be moved.
        // the draggable element becomes 'invalid' and so apply the class here
        $(ui.draggable).addClass(CLASS_INVALID);
    },
    out : function(event, ui) {               
         // the element has exited the overlapped droppable now
         // So element is valid now and so remove the invalid class from it
         $(ui.draggable).removeClass(CLASS_INVALID);
    }
});

#4 楼

function collidesWith (element1, element2) {
    var Element1 = {};
    var Element2 = {};

    Element1.top = $(element1).offset().top;
    Element1.left = $(element1).offset().left;
    Element1.right = Number($(element1).offset().left) + Number($(element1).width());
    Element1.bottom = Number($(element1).offset().top) + Number($(element1).height());

    Element2.top = $(element2).offset().top;
    Element2.left = $(element2).offset().left;
    Element2.right = Number($(element2).offset().left) + Number($(element2).width());
    Element2.bottom = Number($(element2).offset().top) + Number($(element2).height());

    if (Element1.right > Element2.left && Element1.left < Element2.right && Element1.top < Element2.bottom && Element1.bottom > Element2.top) {
        // Do your stuff here
    }
}

#5 楼

$(draggable).bind( 
   "collision",
   function(event,ui) {
      ...
   }
);

#6 楼

function CheckDiv()
{
var ediv1 = document.getElementById('DIV1');
var ediv2 = document.getElementById('DIV2');

 ediv1.top = $(ediv1).offset().top;
 ediv1.left = $(ediv1).offset().left;
 ediv1.right = Number($(ediv1).offset().left) + Number($(ediv1).width());
 ediv1.bottom = Number($(ediv1).offset().top) + Number($(ediv1).height());

 ediv2.top = $(ediv2).offset().top;
 ediv2.left = $(ediv2).offset().left;
 ediv2.right = Number($(ediv2).offset().left) + Number($(ediv2).width());
 ediv2.bottom = Number($(ediv2).offset().top) + Number($(ediv2).height());

if (ediv1.right > ediv2.left && ediv1.left < ediv2.right && ediv1.top < ediv2.bottom && ediv1.bottom > ediv2.top)
 {
alert("hi");
}

if (ediv1.left > ediv2.left && ediv1.top > ediv2.top && ediv1.right < ediv2.right && ediv1.bottom < ediv2.bottom)
 {
alert("hello");
    }
}

#7 楼

function isOverlapping(div1, div2){
    const div1 = div1.getBoundingClientRect();
    const div2 = div2.getBoundingClientRect();
    return (div1.right > div2.left && 
            div1.left < div2.right && 
            div1.bottom > div2.top && 
            div1.top < div2.bottom)
}