did you tried this:

                                var option = new Element('option', {
                                        'selected': true,
                                        'value': "myValue"
                                }

cheers hamburger

> How can i get mootools to actually write the "selected" property into
> the HTML when creating new <option> elements?

> It seems to select the option fine but it doesn't actually write the
> property to the html

> Steve

for me it seems to work fine. (firefox 11) option 3 is selected.

> <option selected="selected" value="3">option 3</option>

> -----Original Message-----
> From: hamburger [mailto:bilidi...@web.de]
> Sent: Monday, 23 April 2012 11:09 PM
> To: MooTools Users
> Subject: [Moo] Re: selectbox options "selected"

> for me it seems to work fine. (firefox 11) option 3 is selected.

The Element.js file in MooTools core handles some attributes in a custom
manner. From a programmatic js perspective, I rarely encounter a need for
the HTML attribute. However, I _have_ encountered such a
need: when I want to reset for values to their original state. In this case,
I use:

this.getElements('option[selected=true]').each(function(o)
{ o.selected = true });

which requires an HTML 'selected' attribute.

You can use this:

document.id('someOptionIDTag').setAttribute('selected', 'selected');

But, that is, er, less than elegant.

The rest of my comments apply to:

https://github.com/mootools/mootools-core/blob/master/Source/Element/...
.js

Starting @ line 540, bools defined boolean attributes (including
'selected') and added a propertySetters function to simply call:

propertySetters[{'selected'}] = function (node, value) {
        node[bool] = !!value;
};

This is why you don't see an HTML attribute for the 'selected'
property you are passing.

Element.js could be modified as follows, starting @ line 561, but I'm not
sure if this would break other behavior:

Object.append(propertySetters, {

        'class': function (node, value) {
                ('className' in node) ? node.className = value :
node.setAttribute('class', value);
        },

        'for': function (node, value) {
                ('htmlFor' in node) ? node.htmlFor = value :
node.setAttribute('for', value);
        },

        'style': function (node, value) {
                (node.style) ? node.style.cssText = value :
node.setAttribute('style', value);
        },

        // handle 'selected' in both the javascript and HTML?
        'selected': function (node, value) {
                node.selected = !!value; // not sure you really need this if
you have the next line(s)
                if (value) node.setAttribute('selected', 'selected');
                else node.removeProperties('selected');
        }

});

I'll defer to others regarding the wisdom of such an override.

Eric

On Apr 23, 9:56 am, "Steve Onnis" <st...@cfcentral.com.au> wrote:
> I know it selects it, but the actual HTML it renders i am expecting is

> <option selected="selected" value="3">option 3</option>

> -----Original Message-----
> From: hamburger [mailto:bilidi...@web.de]
> Sent: Monday, 23 April 2012 11:09 PM
> To: MooTools Users
> Subject: [Moo] Re: selectbox options "selected"

> for me it seems to work fine. (firefox 11) option 3 is selected.

> That would mean you would have to set an ID for every option and then
> reference it after it has been added to the DOM before you could even set
> the property on it.  Kinda dumb yeah?

> -----Original Message-----
> From: Eric Patrick [mailto:epatr...@quandis.com]
> Sent: Tuesday, 24 April 2012 12:45 AM
> To: MooTools Users
> Subject: [Moo] Re: selectbox options "selected"

> The Element.js file in MooTools core handles some attributes in a custom
> manner. From a programmatic js perspective, I rarely encounter a need for
> the HTML attribute. However, I _have_ encountered such a
> need: when I want to reset for values to their original state. In this
> case,
> I use:

> this.getElements('option[selected=true]').each(function(o)
> { o.selected = true });

> which requires an HTML 'selected' attribute.

> You can use this:

> document.id('someOptionIDTag').setAttribute('selected', 'selected');

> But, that is, er, less than elegant.

> The rest of my comments apply to:

> https://github.com/mootools/mootools-core/blob/master/Source/Element/...
> .js

> Starting @ line 540, bools defined boolean attributes (including
> 'selected') and added a propertySetters function to simply call:

> propertySetters[{'selected'}] = function (node, value) {
>         node[bool] = !!value;
> };

> This is why you don't see an HTML attribute for the 'selected'
> property you are passing.

> Element.js could be modified as follows, starting @ line 561, but I'm not
> sure if this would break other behavior:

> Object.append(propertySetters, {

>         'class': function (node, value) {
>                 ('className' in node) ? node.className = value :
> node.setAttribute('class', value);
>         },

>         'for': function (node, value) {
>                 ('htmlFor' in node) ? node.htmlFor = value :
> node.setAttribute('for', value);
>         },

>         'style': function (node, value) {
>                 (node.style) ? node.style.cssText = value :
> node.setAttribute('style', value);
>         },

>         // handle 'selected' in both the javascript and HTML?
>         'selected': function (node, value) {
>                 node.selected = !!value; // not sure you really need this
> if
> you have the next line(s)
>                 if (value) node.setAttribute('selected', 'selected');
>                 else node.removeProperties('selected');
>         }

> });

> I'll defer to others regarding the wisdom of such an override.

> Eric

> On Apr 23, 9:56 am, "Steve Onnis" <st...@cfcentral.com.au> wrote:
> > I know it selects it, but the actual HTML it renders i am expecting is

> > <option selected="selected" value="3">option 3</option>

> > -----Original Message-----
> > From: hamburger [mailto:bilidi...@web.de]
> > Sent: Monday, 23 April 2012 11:09 PM
> > To: MooTools Users
> > Subject: [Moo] Re: selectbox options "selected"

> > for me it seems to work fine. (firefox 11) option 3 is selected.

>  You can't, obj.setProperty('selected', 'true'); will just set the value
> to true.  
> Best you can do is to set _selected to true then with regex you can change
> _selected to selected,

> I wrote this awhile back:
> http://jsfiddle.net/hazlema/BwczU/

> Ran into the same issue.  Thats how I delt with it.

> On 4/23/2012 12:16 AM, Steve Onnis wrote:

>  How can i get mootools to actually write the “selected” property into
> the HTML when creating new <option> elements?

> It seems to select the option fine but it doesn’t actually write the
> property to the html

> Steve