Re: WOImage
Re: WOImage
- Subject: Re: WOImage
- From: Art Isbell <email@hidden>
- Date: Thu, 13 Feb 2003 16:02:02 -1000
On Thursday, February 13, 2003, at 02:53 PM, Jonathan Fleming wrote:
Can someone please inform me as to why I have to link to an image
through an aggregate key when using a path through your EOModel
entities to get my image to show in a WOImage?
If I understand what you're doing, you are occasionally getting an
image through an aggregate key because aggregate keys, unlike the
arrays upon which they act, return a single object. A WOImage requires
a single NSData object, so just because you *can* bind a path to a
WOImage key doesn't mean doing so is correct.
What sense does tbClient.tbClientDatas.thumbnail make as a value to
bind to a key that requires a single object? tbClient.tbClientDatas is
an array of multiple objects, so what do you expect
tbClient.tbClientDatas.thumbnail to be? It's an array of thumbnail
objects, not a single thumbnail object which is what a WOImage key
requires.
When bound through @avg i get:
java.lang.IllegalStateException: URL may only contain 8-Bit characters!
What sense does taking the average of an array of TbClientData objects
make?! Are you really surprised that this didn't work?
When bound through @count, I get:
java.lang.ClassCastException
What do you suppose the count of an array is? An integer, yet you're
binding this to a NSData key. An int or Integer cannot be cast to an
NSData object, so you get a ClassCastException.
When bound through @max, I get the loaded picture
When bound through @min, I get the loaded picture
You're just getting lucky, then, because how do you define the min or
max of an array of TbClientData objects? The implementation of min and
max must just punt and return either the first or last object in the
array.
When bound through @sum, I get error as in @avg
Are you surprised?!
WO requires some exercise of one's gray matter. You can't just bind
any value to any key just because WOB allows you to do so. You've got
to think about what you're doing. Certainly the meanings of @avg,
@count, @max, @min, @sum should be pretty obvious to any
English-speaker.
If a path available in WOB doesn't resolve to what a key requires,
then you'll have to write some Java code to get the necessary value and
bind either the component instance variable set by this code or
returned by a method you write. Or you could bind
tbClient.tbClientDatas.thumbnail to the "list" key of a WORepetition
containing a WOImage such that all tbClient's images will be displayed
at once.
Think before you bind!!
Art
http://homepage.mac.com/aisbell/
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| References: | |
| | >WOImage (From: "Jonathan Fleming" <email@hidden>) |