Re: IE7 Printing WOImage issues

On Feb 8, 2008, at 1:01 PM, Brian Lakeman wrote:

> I've been banging my head against the wall trying to work around  
> this issue:
>
> I've got a WOImage that uses the data attribute bound to an NSData  
> object
> to provide the image, and the mimeType defined accordingly.
>
> When viewing this in IE7 the image displays fine, if I try to print  
> the page, the image doesn't show up on the printout.  If you right- 
> click on the image and try to "Save Picture as...", you get "error  
> 800700de".
>
> Works fine in other browsers.  If the WOImage is bound with the  
> filename attribute, it prints just fine in IE7.
>
> I wrote a little app that displays /Library/WebServer/Documents/ 
> apache_pb.gif twice.  One referenced with the filename attribute,  
> the other one referenced by the data attribute bound to an NSData  
> object populated by reading that file.  One image prints, the other  
> one doesn't.
>
> I'm using WO 5.3 running on OS X Tiger.
>
> I wish I could tell all the users to not use IE7, but that's not an  
> option.


Having seen similar situations, I think I know what is going on  
here.  The problem is that other browsers use the image they have  
cached when they rendered that page.  However IE7 prints, it wants to  
download it again.  That interacts with how the WOResourceManager  
manages memory: after a resource is requested once, it is discarded.

For one way around this, see the WOImage binding "key":
A string that the application uses as a key for caching the data  
specified in data. If you do not provide a key, the data object must  
be fetched each time it is needed. For further information, see the  
reference documentation for the WOResourceManager class, particularly  
that for the flushDataCache method.

I think this means that if you give a key, then _you_ are responsible  
for getting that data (image) out of the cache (e.g. when the page is  
finalized).

You might be able to use a direct action to return the image, it very  
much depends on your logic surrounding this image.

Chuck


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