77755 - async loads triggered in onload handler need care

Status: RESOLVED WORKSFORME

(SeaMonkey :: UI Design, defect)

Description

[Dan M]

Partly this is an information bug, and partly an extension of a bug 76350 that I 
just fixed. The problem is that commonDialogs.xul is too clever. More precisely, 
the dialog loads without an icon specified, then in its onload handler triggers a 
CSS rule that fires an asynchronous load of the correct icon. This makes the icon 
trickle in after the window has been loaded and shown and sized to content.

This is hardly a killer problem, but it does cause arguably unexpected behaviour. 
Alert windows tend to be slightly too small on their first instantiation, and 
then subsequently correct themselves. I've fixed this by hardwiring the icons' 
sizes in global.css, so the document will know the size of that element in its 
onload handler and be able to size itself correctly.

The moral is, care is wanted when firing off asynchronous loads in an onload 
handler. I've just slapped on some care that may bite us some day, hardwiring 
image sizes and all. Blizzard would be happier if commonDialog were designed to 
have icon in hand by the time it hits its onload handler. I don't see how to do 
that without preloading all four, but maybe you guys do.

Comment 1

[Ben Goodger (use ben at mozilla dot org for email)]

Interesting. Thanks for figuring this one out, dan... it baffled me for some 
time. I don't see anything wrong with what you've done in global.css, the icons 
are typically standard sized. 

I'm going to close this as worksforme as your solution in the themes 
worksforme ;) I appreciate the info.