RJS Chaining Problem

rubyonrails-talk
1

Hi,

I am having a problem with the way RJS generates code. Say I have html like this:

    <div id="parent">       <div id="child1"></div>       <div id="child2"></div>     </div>

and RJS code like this:

    parent = page["parent"]     parent.down('#child1').highlight     parent.down('#child2').highlight

the generated JS code becomes:

    $("1").down("#a").highlight().down("#b").highlight();

which is incorrect, because the second down() starts from within #child1, whereas it should have started from within #parent.

By not declaring the "parent" variable and use page["parent"] for every highlight() call it would work, but it's not very DRY. I could also append a bunch of up() and down() in a long chain, but the code gets messy difficult to follow.

I was wondering if there are any good ways to generate code that are correct, clean, and DRY?

Thanks in advance!

Bob

2

Hi Bob,

I am having a problem with the way RJS generates code. Say I have html like this:

    <div id="parent">       <div id="child1"></div>       <div id="child2"></div>     </div>

and RJS code like this:

    parent = page["parent"]     parent.down('#child1').highlight     parent.down('#child2').highlight

the generated JS code becomes:

    $("1").down("#a").highlight().down("#b").highlight();

which is incorrect, because the second down() starts from within #child1, whereas it should have started from within #parent.

By not declaring the "parent" variable

I think maybe the problem you're having results from declaring a variable, and perhaps naming a DOM element, 'parent'. parent is a Javascript property; as in:

window.parent

Try using a different name and see if the problem persists.

HTH, Bill

3

Oh, actually it's just a simplified example code to focus on the concept. The problem is that when I use a ruby variable containing an element multiple times, RJS chains them together while disregarding the traversal methods, which generates incorrect code.