img is declared globally which is not really good, try this: var Songlist = { initialize: function() { this.img = $(document.createElement('img')); this.img.observe('mouseover', Songlist.mouseover); $('body').insert(this.img); } mouseover: function() { this.src = 'anotherimage.gif'; }
} Songlist.initialize(); - kangax On May 18, 9:46 am, "[EMAIL PROTECTED]" <[EMAIL PROTECTED]> wrote: > No problem. I read the texts you posted last time, so I think I now > know, > what "this" does :-) > This time I, of course, wanted to "this" to be the img to easily > change > the source. > > On 18 Mai, 15:36, "T.J. Crowder" <[EMAIL PROTECTED]> wrote: > > > > ..."this" will be the window object, not an instance of Songlist. > > > Doh! Sorry, I forgot, it won't be window, it'll be the img element. > > I keep forgetting that Prototype's event hooking stuff will default > > 'this' in the handler to the element on which the event occurred. My > > bad, apologies. > > -- > > T.J. Crowder > > tj / crowder software / com > > > On May 18, 2:32 pm, "T.J. Crowder" <[EMAIL PROTECTED]> wrote: > > > > Hi, > > > > No, that code probably doesn't do what you mean it to do -- your code > > > hooking the event: > > > > > img.observe('mouseover', Songlist.mouseover); > > > > ...doesn't preserve "this" (as we discussed in another thread). > > > Consequently when this code gets called: > > > > > mouseover: function() { > > > > this.src = 'anotherimage.gif'; > > > > } > > > > ..."this" will be the window object, not an instance of Songlist. > > > > It's really worth stopping coding for a moment and reading up on how > > > "this" works in JavaScript. I've pointed you to this blog entry > > > before:http://blog.niftysnippets.org/2008/04/you-must-remember-this.html > > > > Additionally, Flanagan's book will pay you back in time savings pretty > > > much any time you spend reading > > > it:http://www.oreilly.com/catalog/jscript5/http://www.amazon.com/dp/0596... > > > > In terms of the actual problem with the above code, as with last time, > > > you want to use > > > bindAsEventListener:http://www.prototypejs.org/api/function/bindAsEventListener > > > > Hope this helps, > > > -- > > > T.J. Crowder > > > tj / crowder software / com > > > On May 18, 12:31 pm, "[EMAIL PROTECTED]" > > > > <[EMAIL PROTECTED]> wrote: > > > > OK, I really tried hard before I posted the above message, but sitting > > > > on the toilet I found the mistake. > > > > The code must look like that, than it works: > > > > > var Songlist = { > > > > initialize: function() { > > > > img = document.createElement('img'); > > > > [...] > > > > img.observe('mouseover', Songlist.mouseover); > > > > $('body').insert(img); > > > > } > > > > mouseover: function() { > > > > this.src = 'anotherimage.gif'; > > > > } > > > > > } > > > > > Songlist.initialize(); > > > > > On 18 Mai, 13:25, "[EMAIL PROTECTED]" > > > > > <[EMAIL PROTECTED]> wrote: > > > > > Hello, > > > > > > I habe a problem with the following code (shortened): > > > > > > var Songlist = { > > > > > initialize: function() { > > > > > img = document.createElement('img'); > > > > > [...] > > > > > img.observe('mouseover', this.mouseover); > > > > > $('body').insert(img); > > > > > } > > > > > mouseover: function() { > > > > > this.src = 'anotherimage.gif'; > > > > > } > > > > > > } > > > > > > Songlist.initialize(); > > > > > > Passing the image with my mouse I always get the error: "handler has > > > > > no properties"! > > > > > I would be happy if you gave me a tip, where what causes this error! > > > > > > M. Hoffmann --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Spinoffs" group. To post to this group, send email to rubyonrails-spinoffs@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/rubyonrails-spinoffs?hl=en -~----------~----~----~----~------~----~------~--~---