Thanks ,
I am trying to turn a ‘Drag & Drop Single Div code’ into ‘DnD Multiple Divs code’ .
I like the ‘Single DnD Div Code’ very much because it is very fast .
The ‘who clicked me’ part works fine .
<script>
var e ;
var elmnt ;
var eventHold ;
var holdTargetId ;
var holdTarget ;
var theParent = document.querySelector("#elemContainer");
theParent.addEventListener("click", whoClickedMe, false);
function whoClickedMe(e) {
if (e.target !== e.currentTarget) {
var holdTarget = e.target.id;
alert("He did = " + holdTarget);
dragElement() ;
}
e.stopPropagation();
}
</script>But I’m stuck on the DnD part , how to call ‘function dragElement()’ , etc. .
Here is the original code: (and below that is the current Problem code .)
<!DOCTYPE html>
<html>
<style>
#mydiv {
position: absolute;
z-index: 9;
background-color: #f1f1f1;
text-align: center;
border: 1px solid #d3d3d3;
}
#mydivheader {
padding: 10px;
cursor: move;
z-index: 10;
background-color: #2196F3;
color: #fff;
}
</style>
<body>
<h1>Draggable DIV Element</h1>
<p>Click and hold the mouse button down while moving the DIV element</p>
<div id="mydiv">
<div id="mydivheader">Click here to move</div>
<p>Move</p>
<p>this</p>
<p>DIV</p>
</div>
<script>
//Make the DIV element draggagle:
dragElement(document.getElementById("mydiv"));
function dragElement(elmnt) {
var pos1 = 0, pos2 = 0, pos3 = 0, pos4 = 0;
if (document.getElementById(elmnt.id + "header")) {
/* if present, the header is where you move the DIV from:*/
document.getElementById(elmnt.id + "header").onmousedown = dragMouseDown;
} else {
/* otherwise, move the DIV from anywhere inside the DIV:*/
elmnt.onmousedown = dragMouseDown;
}
function dragMouseDown(e) {
e = e || window.event;
e.preventDefault();
// get the mouse cursor position at startup:
pos3 = e.clientX;
pos4 = e.clientY;
document.onmouseup = closeDragElement;
// call a function whenever the cursor moves:
document.onmousemove = elementDrag;
}
function elementDrag(e) {
e = e || window.event;
e.preventDefault();
// calculate the new cursor position:
pos1 = pos3 - e.clientX;
pos2 = pos4 - e.clientY;
pos3 = e.clientX;
pos4 = e.clientY;
// set the element's new position:
elmnt.style.top = (elmnt.offsetTop - pos2) + "px";
elmnt.style.left = (elmnt.offsetLeft - pos1) + "px";
}
function closeDragElement() {
/* stop moving when mouse button is released:*/
document.onmouseup = null;
document.onmousemove = null;
}
}
</script>
</body>
</html>Here is the problem code:
Here are the Errors:
Uncaught TypeError: Cannot set properties of undefined (setting 'onmousedown')
at dragElement (DnD-Multiple-DIVs.html:66:22)
at HTMLDivElement.whoClickedMe
// line# 52: dragElement() ;
// line# 66 elmnt.onmousedown = dragMouseDown;
<!DOCTYPE html>
<html><head><meta http-equiv="Content-Type" content="text/html; charset=windows-1252">
<style>
img {
margin: 5px;
padding: 5px 8px;
outline: none;
border: none;
color: white;
font-size: 1em;
}
div:hover {
// background-color: #ffa000;
cursor: pointer;
}
#result {
border:1px solid;
display:inline-block;
margin:5px;
/* padding:5px; */
}
</style>
</head>
<body>
<div id="elemContainer" style="position: absolute; width: 1420px; height: 750px; display:inline-block; ">
<div class="item" id="elem1" draggable="true" style="border-radius: 50%; width:32px; height:32px; position: relative; float:left; left: 30%; top:0; background-color: #FF0004;"> 1</div>
<div class="item" id="elem2" draggable="true" style="border-radius: 50%; width:32px; height:32px; position: relative; float:left; left: 31%; top: 0; background-color: #FE8E05;"> 2</div>
</div> <!-- id="elemContainer" -->
<div id="result">result = </div>
<script>
var e ;
var elmnt ;
var eventHold ;
var holdTargetId ;
var holdTarget ;
var theParent = document.querySelector("#elemContainer");
theParent.addEventListener("click", whoClickedMe, false);
function whoClickedMe(e) {
if (e.target !== e.currentTarget) {
var holdTarget = e.target.id;
alert("He did = " + holdTarget);
dragElement() ;
}
e.stopPropagation();
}
</script>
<script>
function dragElement() {
console.log("function dragElement(holdTarget = " + holdTargetId) ;
elmnt = holdTarget ;
// var savedTargetId = event.target.id ;
var pos1 = 0, pos2 = 0, pos3 = 0, pos4 = 0;
elmnt.onmousedown = dragMouseDown;
}
function dragMouseDown(e) {
e = e || window.event;
e.preventDefault();
console.log("function dragMouseDown(e)") ;
// get the mouse cursor position at startup:
pos3 = e.clientX;
pos4 = e.clientY;
document.onmouseup = closeDragElement;
// call a function whenever the cursor moves:
document.onmousemove = elementDrag;
}
function elementDrag(e) {
e = e || window.event;
e.preventDefault();
//console.log("function elementDrag(e)") ;
// calculate the new cursor position:
pos1 = pos3 - e.clientX;
pos2 = pos4 - e.clientY;
pos3 = e.clientX;
pos4 = e.clientY;
// set the element's new position:
elmnt.style.top = (elmnt.offsetTop - pos2) + "px";
elmnt.style.left = (elmnt.offsetLeft - pos1) + "px";
}
function closeDragElement() {
/* stop moving when mouse button is released:*/
//console.log("function closeDragElement()")
document.onmouseup = null;
document.onmousemove = null;
}
</script>
</body></html>Thank you for your Help.