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In Version 2.01, a new layer was created to contain and manipulate the fade-workaround GIF. The relevant statements were in the FDRinit() function:
elGif = new Layer(contWidth,elCont);
imStr = "<IMG SRC=" + FDRgifSrc +" WIDTH="
+ Math.max(FDRfadeImg.width,(FDRboxWid - (FDRborWid*2)))
+">"
with (elGif) {
document.write(imStr);
document.close();
moveAbove(elNews);
}
imgHeight = elGif.document.height;
slideInc = (imgHeight/(FDRblendDur*1000/FDRgifInt));
startTop = -(imgHeight - FDRboxHgt);
The above statements should only kick in if a fader is called for, that is, if FDRjustFlip is false.
if (!FDRjustFlip) {
elGif = new Layer(contWidth,elCont);
imStr = "<IMG SRC=" + FDRgifSrc +" WIDTH="
+ Math.max(FDRfadeImg.width,(FDRboxWid-(FDRborWid*2)))
+">"
with (elGif) {
document.write(imStr);
document.close();
moveAbove(elNews);
}
imgHeight = elGif.document.height;
slideInc = (imgHeight/(FDRblendDur*1000/FDRgifInt));
startTop = -(imgHeight - FDRboxHgt);
}
Whenever a fade transition begins, the GIF layer is re-positioned and made visible to hide the displayed headline with these statements in FDRfade():
if (NS4) {
elGif.top = startTop; // GIF is positioned
elGif.visibility = "inherit"; // and made visible
elNews.visibility = "hide";
with (elNews.document) {
write(newsStr);
close();
}
elNews.visibility = "inherit";
}
Again, these statements should not be executed if we want to flip between headlines, so in Version 3, they are executed conditionally:
if (NS4) {
if (!FDRjustFlip) {
elGif.top = startTop;
elGif.visibility = "inherit";
}
elNews.visibility = "hide";
with (elNews.document) {
write(newsStr);
close();
}
elNews.visibility = "inherit";
}
To achieve the fade-workaround, by moving the GIF vertically, FDRslide() is called at the end of FDRfade():
function FDRfade() {
.
.
.
if (NS4) FDRslide();
}
Of course, in Version 3, we add a condition:
function FDRfade() {
.
.
.
if (NS4 && !FDRjustFlip) FDRslide();
}
We have now ensured that Navigator will not load the GIF image required for the fade workaround, and will not execute any GIF-related statements. Consequently, the Fader display will flip between headlines. On the next page, we'll make a couple of flipping-related Explorer code changes.
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Created: Nov 30, 1999
Revised: Nov 30, 1999
URL: http://www.webreference.com/dhtml/column27/fade3flipns.html
