for this page
if (hintToolTipStarted == 'fail') {
return; // without attempting to do anything
} else if (hintToolTipStarted == 'no') {
div = document.createElement('div');
div.setAttribute('id', 'hintToolTipDiv');
div.style.zIndex = 900;
document.body.appendChild(div);
hintToolTipStarted = (hintToolTipDiv = document.getElementById('hintToolTipDiv')) == null ? 'fail' : 'yes';
}
showHintX(hintHTML, (ie4 ? event.srcElement : event.target), hintWidth, hintToolTipDiv);
//
// arrange for this
to be hidden at next 'mouseout' event received by target
if (ie4) {
// hide overlapping selects (IE4..6 only)
var c = document.getElementsByTagName('select');
var i;
for (i = 0; i < c.length; i++) {
if ((c[i].style.visibility == '' || c[i].style.visibility == 'visible') && overlaps(c[i], hintToolTipDiv)) { // wot if it's 'inherit'?
c[i].style.visibility = 'hidden';
hintHiddenToolTipSelects.push(c[i]);
}
}
event.srcElement.onmouseout = hideToolTip; // tell IE4+ to hide ToolTip at next mouseout
} else {
event.target.onmouseout = hideToolTip; // tell DOM 2 browser to hide ToolTip at next mouseout
}
}
function showInfoBox(event, hintHTML, hintWidth) { // shows HTML in a box of Width until shown elsewhere or background is clicked
var ie4 = event.srcElement != null; // not a DOM Level 2 browser
var div; // temp for creating hintInfoBoxDiv
//
// lazily create the InfoBox
for this page
if (hintInfoBoxStarted == 'fail') { // we've already tried & failed (how?) to create hintInfoBoxDiv
return; // without attempting to do anything
} else if (hintInfoBoxStarted == 'no') { // this is the first call
div = document.createElement('div');
div.setAttribute('id', 'hintInfoBoxDiv');
div.style.zIndex = 800; // beneath hintToolTipDiv
document.body.appendChild(div);
if ((hintInfoBoxDiv = document.getElementById('hintInfoBoxDiv')) == null) { // somehow (how?) failed to create this element
hintInfoBoxStarted = 'fail';
} else {
hintInfoBoxStarted = 'yes';
// arrange to hide InfoBox when user clicks anywhere on page
chainFunc(document.body, 'onclick', hideInfoBox); // call once only, iff hintInfoBoxDiv was created
}
}
showHintX(hintHTML, (ie4 ? event.srcElement : event.target), hintWidth, hintInfoBoxDiv);
//
if (ie4) {
// hide overlapping selects (IE4..6 only)
var c = document.getElementsByTagName('select');
var i;
for (i = 0; i < c.length; i++) {
if ((c[i].style.visibility == '' || c[i].style.visibility == 'visible') && overlaps(c[i], hintInfoBoxDiv)) { // wot if it's 'inherit'?
c[i].style.visibility = 'hidden';
hintHiddenInfoBoxSelects.push(c[i]);
}
}
event.cancelBubble = true; // prevent this 'click' being propagated (as it would by default) to ancestor elements
} else {
event.stopPropagation(); // ditto
}
}
function showHint(hintHTML, obj, hintWidth) { // deprecated, legacy version
var div; // temp for creating hintToolTipDiv
if (hintToolTipStarted == 'fail') {
return; // without attempting to do anything
} else if (hintToolTipStarted == 'no') {
div = document.createElement('div');
div.setAttribute('id', 'hintToolTipDiv');
document.body.appendChild(div);
hintToolTipStarted = (hintToolTipDiv = document.getElementById('hintToolTipDiv')) == null ? 'fail' : 'yes';
}
showHintX(hintHTML, obj, hintWidth, hintToolTipDiv);
obj.onmouseout = hideToolTip;
}
function showHintX(hintHTML, obj, hintWidth, hintDiv) { // private method serving above three public methods
var posn; // temp for element origin
var vX0; // left edge of viewport
var vX1; // right "
var vY0; // top "
var vY1; // bottom "
var vW; // width of viewport
var vH; // height "
var eX0; // left edge of element for which hint is to be shown
var eX1; // right edge "
var eY0; // top edge "
var eY1; // bottom edge "
var eW; // width of element
var eH; // height "
var eXmid; // horizontal midpoint of element
var eYmid; // vertical "
var lW; // width of rectangular region of viewport to left of element
var lH; // height ditto
var tW; // width ditto to topwards of element
var tH; // height ditto
var rW; // width ditto to right of element
var rH; // height ditto
var bW; // width ditto to bottomwards of element
var bH; // height ditto
var where; // chosen location of hint div
vX0 = getViewportLeft();
vW = getViewportWidth();
vX1 = vX0 + vW;
vY0 = getViewportTop();
vH = getViewportHeight();
vY1 = vY0 + vH;
posn = elementTopLeft(obj);
eX0 = posn[0];
eY0 = posn[1];
eW = obj.offsetWidth;
eH = obj.offsetHeight;
eX1 = eX0 + eW;
eY1 = eY0 + eH;
eXmid = (eX0 + eX1)/2;
eYmid = (eY0 + eY1)/2;
// width, height of viewport regions around element (any of these may be <=0)
lW = eX0 - vX0;
lH = vY1 - vY0;
tW = vX1 - vX0;
tH = eY0 - vY0;
rW = vX1 - eX1;
rH = vY1 - vY0;
bW = vX1 - vX0;
bH = vY1 - eY1;
// lay out the hint box:
hintDiv.style.width = (hintWidth == null ? '300px' : hintWidth);
hintDiv.innerHTML = hintHTML;
// get its size and choose where best to put it:
pW = hintDiv.offsetWidth;
pH = hintDiv.offsetHeight;
if (pW <= vW && pH <= tH) { // there is room within viewport above element
where = "top";
} else if (pH <= vH && pW <= lW) { // there is room within viewport to left of element
where = "left";
} else if (pH <= vH && pW <= rW) { // there is room within viewport to right of element
where = "right";
} else if (pW <= vW && pH <= bH) { // there is room within viewport below
where = "bottom";
} else if (exposedFraction(pW, pH, rW, rH) > exposedFraction(pW, pH, bW, bH)) {
where = "right";
} else {
where = "bottom";
}
// compute hint box position within its chosen location:
if (where == "top" || where == "bottom") {
if (eXmid - pW / 2 < vX0) { // if, horiz centred wrt element, right edge is outside viewport
pX0 = vX0;
} else if (eXmid + pW / 2 > vX1) { // else if, similarly aligned, left edge is outside viewport
pX0 = vX1 - pW;
} else {
pX0 = eXmid - pW / 2; // else centre it
}
} else if (where == "left") {
if (vX0 > eX0 - 5 - pW) {
pX0 = vX0;
} else {
pX0 = eX0 - pW - 5;
}
} else if (where == "right") {
if (vX1 < eX1 + pH) { // not enough room at right for popup width
pX0 = eX1; // show immediately at right of element
} else if (vX1 < eX1 + pH + 5) { // 0..5 pixels to spare
pX0 = eX1 + (vX1 - eX1 - pW); // split the difference
} else {
pX0 = eX1 + 5; // show 5 pixels to right of element
}
} else { // shouldn't happen
pX0 = vX1 + 1; // hide beyond viewport
}
if (where == "left" || where == "right") {
if (eYmid - pH / 2 < vY0) {
pY0 = vY0;
} else if (eYmid + pH / 2 > vY1) {
pY0 = vY1 - pH;
} else {
pY0 = eYmid - pH / 2;
}
} else if (where == "top") {
if (vY0 > eY0 - 5 - pH) {
pY0 = vY0;
} else {
pY0 = eY0 - pH - 5;
}
} else if (where == "bottom") {
if (vY1 < eY1 + pH) { // not enough room at bottom for popup height
pY0 = eY1; // show immediately below element
} else if (vY1 < eY1 + 5 + pH) { // 0..5 pixels to spare
pY0 = eY1 + (vY1 - eY1 - pH) / 2; // split the difference
} else {
pY0 = eY1 + 5; // show 5 pixels below element
}
} else { // shouldn't happen
pY0 = vY1 + 1; // hide beyond viewport
}
// position and show the hint box:
hintDiv.style.left = pX0 + 'px';
hintDiv.style.top = pY0 + 'px';
hintDiv.style.visibility = 'visible';
}
function hideToolTip() {
hintToolTipDiv.style.visibility = 'hidden';
hintToolTipDiv.style.left = '-500px'; // for good measure
// show any temporarily hidden selects (only happens with non-DOM2 browsers i.e. IE4-6)
var hs;
while ((hs = hintHiddenToolTipSelects.pop()) != undefined) {
hs.style.visibility = 'visible';
}
}
function hideInfoBox() {
hintInfoBoxDiv.style.visibility = 'hidden';
hintInfoBoxDiv.style.left = '-500px'; // for good measure
// show any temporarily hidden selects (only happens with non-DOM2 browsers i.e. IE4-6)
var hs;
while ((hs = hintHiddenInfoBoxSelects.pop()) != undefined) {
hs.style.visibility = 'visible';
}
}
function getViewportWidth() { // by Michael van Ouwerkerk; tweaked by PS
if (document.documentElement && document.documentElement.clientWidth) {
return document.documentElement.clientWidth;
} else if (document.body && document.body.clientWidth) {
return document.body.clientWidth;
} else if (window.innerWidth) {
return window.innerWidth - 18;
} else {
return 0;
}
};
function getViewportHeight() { // by Michael van Ouwerkerk; tweaked by PS
if (document.body && document.body.clientHeight) {
return document.body.clientHeight;
} else if (window.innerHeight) {
return window.innerHeight - 18;
} else if (document.documentElement && document.documentElement.clientHeight) {
return document.documentElement.clientHeight;
} else {
return 0;
}
};
function getViewportLeft() { // by Michael van Ouwerkerk; tweaked by PS
if (document.documentElement && document.documentElement.scrollLeft) {
return document.documentElement.scrollLeft;
} else if (document.body && document.body.scrollLeft) {
return document.body.scrollLeft;
} else if (window.pageXOffset) {
return window.pageXOffset;
} else if (window.scrollX) {
return window.scrollX;
} else {
return 0;
}
};
function getViewportTop() { // by Michael van Ouwerkerk; tweaked by PS
if (document.documentElement && document.documentElement.scrollTop) {
return document.documentElement.scrollTop;
} else if (document.body && document.body.scrollTop) {
return document.body.scrollTop;
} else if (window.pageYOffset) {
return window.pageYOffset;
} else if (window.scrollY) {
return window.scrollY;
} else {
return 0;
}
};
function elementTopLeft(element) { // by Mark Wilton-Jones: despite name, returns [left,top]
var posX;
var posY;
if (element.offsetParent) {
for (posX = 0, posY = 0; element.offsetParent; element = element.offsetParent) {
posX += element.offsetLeft;
posY += element.offsetTop;
}
return [ posX, posY ];
} else {
return [ element.x, element.y ];
}
}
function exposedFraction(aW, aH, bW, bH) { // area fraction of a which intersects with b (same origin)
if (aW <= 0 || aH <= 0 || bW <= 0 || bH <= 0) {
return 0.0;
} else {
return (aW <= bW ? 1.0 : bW / aW) * (aH <= bH ? 1.0 : bH / aH);
}
}
function overlaps(e1, e2) { // returns true iff element e1 overlaps element e2 to any extent
var e1TopLeft = elementTopLeft(e1);
var e1Left = e1TopLeft[0];
var e1Top = e1TopLeft[1];
var e1Bottom = e1Top + e1.offsetHeight;
var e1Right = e1Left + e1.offsetWidth;
var e2TopLeft = elementTopLeft(e2);
var e2Left = e2TopLeft[0];
var e2Top = e2TopLeft[1];
var e2Bottom = e2Top + e2.offsetHeight;
var e2Right = e2Left + e2.offsetWidth;
//
return !(e1Bottom < e2Top || e2Bottom < e1Top || e1Right < e2Left || e2Right < e1Left); // not completely clear of each other
}