Rain Sister's article: The TreeView of the DHTML implementation (you can achieve the drag effect yo)

Last Update:2017-02-28 Source: Internet

Author: User

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Dhtml|treeview tree.htm



<style>
Ie\:tree {display:block;}
Ie\:treeitem {font-weight:expression (This.children.length > 1?) ' Bold ': ' normal '); border-top:2px solid White;display:block; margin-left:20px; Visibility:inherit; Overflow:hidden; width:100%}
Ie\:label {display:inline; Cursor:hand}
</style>
<body style= "Font-family:verdana; font-size:12px ">
<ie:tree id=thetree>
<ie:treeitem><ie:label id=label1>1.0-set</ie:label>
<ie:treeitem><ie:label>1.1 megalosaurus</ie:label></ie:treeitem>
<ie:treeitem><ie:label>1.2 iguanodon</ie:label></ie:treeitem>
<ie:treeitem><ie:label>1.3 hylaeosaurus</ie:label></ie:treeitem>
<ie:treeitem><ie:label>1.4 Tyrannosaurus rex</ie:label></ie:treeitem>
</ie:treeitem>
<ie:treeitem><ie:label>2.0 later set</ie:label>
<ie:treeitem><ie:label>2.1 mammoths</ie:label></ie:treeitem>
<ie:treeitem><ie:label>2.2 mastodons</ie:label>
<ie:treeitem><ie:label>2.2.1 plesiosaurs</ie:label></ie:treeitem>
<ie:treeitem><ie:label>2.2.2 ichthyosaurs</ie:label></ie:treeitem>
<ie:treeitem><ie:label>2.2.3 Dimetrodon </ie:label></ie:treeitem>
<ie:treeitem><ie:label>2.2.4 sinapsid</ie:label></ie:treeitem>
</ie:treeitem>
<ie:treeitem><ie:label>2.3 stegosaurus</ie:label></ie:treeitem>
<ie:treeitem><ie:label>2.4 apatosaurus</ie:label></ie:treeitem>
<ie:treeitem><ie:label>2.5 mammals</ie:label></ie:treeitem>
<ie:treeitem><ie:label>2.6 tetrapods</ie:label>
<ie:treeitem><ie:label>2.6.1 amphibians</ie:label></ie:treeitem>
<ie:treeitem><ie:label>2.6.2 whales</ie:label></ie:treeitem>
<ie:treeitem><ie:label>2.6.3 crocodiles</ie:label></ie:treeitem>
<ie:treeitem><ie:label>2.6.4 Sea turtles</ie:label></ie:treeitem>
</ie:treeitem>
<ie:treeitem><ie:label>2.7 Late permian</ie:label></ie:treeitem>
<ie:treeitem><ie:label>2.8 mesozoic</ie:label></ie:treeitem>
</ie:treeitem>
<ie:treeitem><ie:label>3.0 archosaurs</ie:label>
<ie:treeitem><ie:label>3.1 mandibular fenestra</ie:label></ie:treeitem>
<ie:treeitem><ie:label>3.2 pointed snout</ie:label></ie:treeitem>
<ie:treeitem><ie:label>3.3 theocodant Tooth implantation</ie:label></ie:treeitem>
<ie:treeitem><ie:label>3.4 Modified ankle</ie:label></ie:treeitem>
</ie:treeitem>
<ie:treeitem><ie:label>4.0 mesozoic</ie:label>
<ie:treeitem><ie:label>4.1 Middle Animals</ie:label></ie:treeitem>
</ie:treeitem>
</ie:tree>
<script>
Variables for Drag/drop
var dragelement = null;
var dropelement = null;
var currover = null;

Variables for expanding/collapsing
var flycount = 5;
var msecs = 5;
var currcount = 0;

Event handler Hookup
Thetree.onmousedown = preselect;
Thetree.ondragstart = DragStart;
Thetree.ondragend = Dragend;
Thetree.ondragenter = DragOver;
Thetree.ondragover = DragOver;
Thetree.ondragend = Dragend;
Thetree.ondrop = DragDrop;
Document.onclick = click;

Drag/drop Code

Method called as we start Drag/drop
function DragStart () {
var e;
e = window.event.srcElement;
if (e.tagname!= "label")
return false;

Dragelement = e.parentelement;
}

Called as we mouse over-note that there was special handling for DragOver code
As DragLeave doesn ' t track the toelement/fromelement as Mouseover/mouseout does
function DragOver () {
if (window.event.srcElement.tagName!= "TreeItem")
Return

if (!dragelement.contains (window.event.srcElement)) {
if (currover) {
CurrOver.style.borderTopColor = "";
}
Currover = window.event.srcElement;
Window.event.srcElement.style.borderTopColor = "BLACK";
Event.returnvalue = false;
}
}

Called when drag is Ended-always
function Dragend () {
if (currover) {
CurrOver.style.borderTopColor = "";
}
}

called on Drop
function DragDrop () {
if (currover) {
CurrOver.style.borderTopColor = "";
}
t = currover;
T.parentelement.insertbefore (dragelement, T);
}

needed to select items so they can be dragged
Drag drop only supported on selection and images
function Preselect () {
var e;

e = window.event.srcElement;
if (e.tagname!= "label") {
Return
}
R = Document.body.createTextRange ();
R.movetoelementtext (e);
R.select ();
Window.event.cancelBubble = true;
}

Beginning of Expand/collapse Code

Called to handle document click, starts toggling
function Click () {
if (window.event.srcElement.tagName!= "label") {
Return
}
if (Window.event.srcElement.parentElement.children.length > 1) {
Togglestate (window.event.srcElement.parentElement);
}
}

Toggles expanding/collapse state of Element-does Setup
function Togglestate (e) {
E.oheight = E.scrollheight + 2;
E.style.posheight = E.offsetheight;

if (e.scrollheight >= e.offsetheight) {
Growit (e);
} else {
Shrinkit (e);
}
}

Called to initiate growing a element
function Growit (e) {
Currcount = 0;

Window.settimeout ("Dogrow" ("+ E.uniqueid +"); ", msecs);
}

Called to initiate shrinking a element
function Shrinkit (e) {
Currcount = 0;
Window.settimeout ("Doshrink" ("+ E.uniqueid +"); ", msecs);
}

Inner loop for growing an object
function Dogrow (e) {
var dh;
var lineheight = e.children[0].offsetheight;

currcount++;

DH = e.oheight/flycount;

if (e.style.posheight!= e.oheight) {
E.style.posheight + + dh;
}

if (Currcount < Flycount) {
Window.settimeout ("Dogrow" ("+ E.uniqueid +"); ", msecs);
}
else {
E.style.height = "";
}
}

Inner loop for shrinking an object
function Doshrink (e) {
var dh, DW;
var lineheight = e.children[0].offsetheight;
var p;

currcount++;

DH = (e.oheight-lineheight)/flycount;

E.style.posheight-= DH;

if (Currcount < Flycount) {
Window.settimeout ("Doshrink" ("+ E.uniqueid +"); ", msecs);
}
else {
E.style.posheight = Lineheight;
}
}

</script>
</body>

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