Rails - Jul 2006 - ERb question: Embedding <%= %> in helper method calls

I had a situation where I wanted to use a <%= %> (scriptlet) in my 
text_field call to set the "disabled" attribute on the text field,
like
so:

<%= text_field(:current_job, ''removeLinkPos'', :value =>
'''', :id =>
''offset'', :maxlength => 2, :disabled => <%= sometest
? ''true'' : ''false''
%>) %>

however, this caused a compile error.

I ended up with an if/else statement to generate my text_field 
differently based on the boolean test for "disabledness".

It kind of makes sense to me that doing <%= .... <%= ... %> ...%> 
might
cause problems.

However, is there an alternative way to achieve this behavior, when you 
want to use <%= %> to generate dynamic attributes within the call to a 
helper method?

Thanks,
Wes

-- 
Posted via http://www.ruby-forum.com/.

How about:

def text_field_with_conditional_options(object, method, options={})
    text_field(object, method, options.merge(yield))
end

And the call would be:

<%= text_field_with_conditional_options(:current_job,
''removeLinkPos'',
:value => '''', :id => ''offset'',
:maxlength => 2) {{:disabled => sometest}} %>

I don''t know if this makes things better or worse :-|


On 7/6/06 12:52 PM, "Wes Gamble" <weyus@att.net> wrote:
> I had a situation where I wanted to use a <%= %> (scriptlet) in my
> text_field call to set the "disabled" attribute on the text
field, like
> so:
> 
> <%= text_field(:current_job, ''removeLinkPos'', :value
=> '''', :id =>
> ''offset'', :maxlength => 2, :disabled => <%=
sometest ? ''true'' : ''false''
> %>) %>
> 
> however, this caused a compile error.
> 
> I ended up with an if/else statement to generate my text_field
> differently based on the boolean test for "disabledness".
> 
> It kind of makes sense to me that doing <%= .... <%= ... %>
...%>  might
> cause problems.
> 
> However, is there an alternative way to achieve this behavior, when you
> want to use <%= %> to generate dynamic attributes within the call to
a
> helper method?
> 
> Thanks,
> Wes

Steve Ross wrote:
> How about:
> 
> def text_field_with_conditional_options(object, method, options={})
>     text_field(object, method, options.merge(yield))
> end
> 
> And the call would be:
> 
> <%= text_field_with_conditional_options(:current_job,
''removeLinkPos'',
> :value => '''', :id => ''offset'',
:maxlength => 2) {{:disabled =>
> sometest}} %>
> 
> I don''t know if this makes things better or worse :-|
How does this work?  Would each hash element get looked at to see if it 
was a code block and then, if so, the yield happens?

So options would have keys value, id, maxlength, and then the last key 
would be a code block containing a hash, the yield would happen and when 
complete, you end up with another hash element (with whatever value got 
determined in the block)?

Just trying to make sure I get it.

Interesting.  I agree - not sure if this helps anything :).

Wes

-- 
Posted via http://www.ruby-forum.com/.

How I intended it was that you call it exactly like text_field but specify
any additional options as a hash. These options are merged with the existing
options hash you?ve provided in the original call. The reason for the two
options hashes is that the function signature is what you?re familiar with.
But, now that you mention it, the code should probably be:

def text_field_with_conditional_options(object, method, options={})
    block_given? ?
        text_field(object, method, options.merge(yield)) :
        text_field(object, method, options)
end

That way it doesn?t upchuck if you fail to provide a block.


On 7/6/06 1:44 PM, "Wes Gamble" <weyus@att.net> wrote:
> Steve Ross wrote:
>> > How about:
>> > 
>> > def text_field_with_conditional_options(object, method,
options={})
>> >     text_field(object, method, options.merge(yield))
>> > end
>> > 
>> > And the call would be:
>> > 
>> > <%= text_field_with_conditional_options(:current_job,
''removeLinkPos'',
>> > :value => '''', :id =>
''offset'', :maxlength => 2) {{:disabled =>
>> > sometest}} %>
>> > 
>> > I don''t know if this makes things better or worse :-|
> 
> How does this work?  Would each hash element get looked at to see if it
> was a code block and then, if so, the yield happens?
> 
> So options would have keys value, id, maxlength, and then the last key
> would be a code block containing a hash, the yield would happen and when
> complete, you end up with another hash element (with whatever value got
> determined in the block)?
> 
> Just trying to make sure I get it.
> 
> Interesting.  I agree - not sure if this helps anything :).
> 
> Wes

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> On 7/6/06 12:52 PM, "Wes Gamble" <weyus@att.net> wrote:
>
>> I had a situation where I wanted to use a <%= %> (scriptlet) in
my
>> text_field call to set the "disabled" attribute on the text
field,
>> like
>> so:
>>
>> <%= text_field(:current_job, ''removeLinkPos'',
:value => '''', :id =>
>> ''offset'', :maxlength => 2, :disabled => <%=
sometest ? ''true'' :
>> ''false''
>> %>) %>
>>
>> however, this caused a compile error.
>>
>> I ended up with an if/else statement to generate my text_field
>> differently based on the boolean test for "disabledness".
>>
>> It kind of makes sense to me that doing <%= .... <%= ... %>
...%>
>> might
>> cause problems.
>>
>> However, is there an alternative way to achieve this behavior,  
>> when you
>> want to use <%= %> to generate dynamic attributes within the call
>> to a
>> helper method?
>>
>> Thanks,
>> Wes
On Jul 6, 2006, at 4:35 PM, s.ross wrote:
> How about:
>
> def text_field_with_conditional_options(object, method, options={})
>     text_field(object, method, options.merge(yield))
> end
>
> And the call would be:
>
> <%= text_field_with_conditional_options(:current_job,
''removeLinkPos'',
> :value => '''', :id => ''offset'',
:maxlength => 2) {{:disabled =>
> sometest}} %>
>
> I don''t know if this makes things better or worse :-|
What''s wrong with: (note the trailing . on the 2nd line

<%= text_field(:current_job, ''removeLinkPos'',
                { :value => '''', :id =>
''offset'', :maxlength => 2 }.
	          merge!(sometest ? { :disabled => ''disabled'' } :
{})
               ) %>

No need to get complicated about it.  You''re already doing Ruby in  
the <%= ... %> so just add the code you need.

Now, if you were using this all over the place, then a helper might  
be useful.  In particular, the HTML ''disabled'' attribute
really needs
to be ''disabled="disabled"'' if you want to be XHTML
1.0.  If your
only conditional was to set a field disabled or not, I''d make the  
helper know specifically about the :disabled key and set the options  
hash given to text_field similarly to how I''ve done it above.

-Rob

Rob Biedenharn		http://agileconsultingllc.com
Rob@AgileConsultingLLC.com