Check_box_tag problems

Rails
1

Hi,
I’m having some trouble with my form. The thing is I’m using a loop to
generate check_box_tags and then when the user clicks submit I want to
be able to see what he checked. For each checked box I want to copy a
file to the corresponding directory.

Here’s the form:

<%form_for :cats, :url => {:action => :save_mt} do%>
<[email protected] do |flokkur|%>

<%= check_box_tag("cats[#{flokkur}]",1,false) %> <%= flokkur %>

<%end%> <%= submit_tag "Vista mælitæki", :class => 'submit'%> <%end%>

Development.log shows these parameters have been passed:

Parameters: {“commit”=>“Vista mælitæki”,
“authenticity_token”=>“B2u5ULNr7IJ/ta0+hiAMBjmjEtTtc/yMAQQvSxFn2d0=”,
“cats”=>{“Geðsjúkraþjálfun”=>“1”}}

Here I only checked “Geðsjúkraþjálfun” and then submitted.

The problem is in the controller. How can I loop through the cats hash
and check if the key is there? I now have something like this:

@flokkar.each do |flokkur|
if params[:cats][:flokkur] == 1
…do some stuff…
end
end

#(@flokkar is the array that I used to build the form.)

But i never execute the block inside the if condition check. I’ve also
tried params[:cats][flokkur] but nothing happens. How can I make ruby
check whether a key exists? Like if I had a string “foo” and a hash
“durr”, how could I check if durr[:foo] exists without writing the whole
thing??

BR,
Sindri

2

Hi,

Are you trying to apply a loop on cats hash??

If yes then try this:

@var1 = []
params[:cats].each do |key, value|
@var1 << key
end

if @var1.include?(your_key)
do this
else
do that
end

Regards,

Saurabh

3

Marnen Laibow-Koser wrote:

[…]

This is strange code. You’re inside a form_for, so why are you using
check_box_tag rather than check_box ?

I read somewhere that I shouldn’t do it like this, but I couldn’t get
the info on checked/uncecked using check_box. Should I get rid of the
form_for and change the submit button to POST button_to? Why?

Thanks Saurabh P., ofc I should’ve done that, thanks! :slight_smile:

4

Sindri Guðmundsson wrote:

Hi,
I’m having some trouble with my form. The thing is I’m using a loop to
generate check_box_tags and then when the user clicks submit I want to
be able to see what he checked. For each checked box I want to copy a
file to the corresponding directory.

Here’s the form:

<%form_for :cats, :url => {:action => :save_mt} do%>
<[email protected] do |flokkur|%>

<%= check_box_tag("cats[#{flokkur}]",1,false) %> <%= flokkur %>

<%end%> <%= submit_tag "Vista mælitæki", :class => 'submit'%> <%end%>

[…]

This is strange code. You’re inside a form_for, so why are you using
check_box_tag rather than check_box ?

Best,

Marnen Laibow-Koser
http://www.marnen.org
[email protected]

5

Sindri Guðmundsson wrote:

Marnen Laibow-Koser wrote:

[…]

This is strange code. You’re inside a form_for, so why are you using
check_box_tag rather than check_box ?

I read somewhere that I shouldn’t do it like this, but I couldn’t get
the info on checked/uncecked using check_box. Should I get rid of the
form_for and change the submit button to POST button_to? Why?

No, you should fix the problem that’s preventing you from using
check_box!

Thanks Saurabh P., ofc I should’ve done that, thanks! :slight_smile:

Best,

Marnen Laibow-Koser
http://www.marnen.org
[email protected]

6

If this helps these are the parameters passed when I use check_box:

Parameters: {“commit”=>“Vista mælitæki”,
“authenticity_token”=>“B2u5ULNr7IJ/ta0+hiAMBjmjEtTtc/yMAQQvSxFn2d0=”,
“cats”=>{“flokkur”=>[nil, nil, nil, nil, nil, nil, nil, nil, nil, nil,
nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil]}}

7

Sindri Guðmundsson wrote:

If this helps these are the parameters passed when I use check_box:

Parameters: {“commit”=>“Vista mælitæki”,
“authenticity_token”=>“B2u5ULNr7IJ/ta0+hiAMBjmjEtTtc/yMAQQvSxFn2d0=”,
“cats”=>{“flokkur”=>[nil, nil, nil, nil, nil, nil, nil, nil, nil, nil,
nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil]}}

And what does that version of the view code look like?

Best,

Marnen Laibow-Koser
http://www.marnen.org
[email protected]

8

Marnen Laibow-Koser wrote:

Sindri Guðmundsson wrote:

If this helps these are the parameters passed when I use check_box:

Parameters: {“commit”=>“Vista mælitæki”,
“authenticity_token”=>“B2u5ULNr7IJ/ta0+hiAMBjmjEtTtc/yMAQQvSxFn2d0=”,
“cats”=>{“flokkur”=>[nil, nil, nil, nil, nil, nil, nil, nil, nil, nil,
nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil]}}

And what does that version of the view code look like?

Best,

Marnen Laibow-Koser
http://www.marnen.org
[email protected]

Hi,
It looks like this now;

<%form_for :cats, :url => {:action => :save_mt} do |form|%>
<[email protected] do |flokkur|%>

<%= form.check_box 'flokkur[]' %> <%= flokkur %>

<%end%> <%= submit_tag "Vista mælitæki", :class => 'submit'%> <%end%>

I’ve tried different parameters for the check_box but to no success…

BR,
Sindri

9

Sindri Guðmundsson wrote:

Marnen Laibow-Koser wrote:

Sindri Guðmundsson wrote:

If this helps these are the parameters passed when I use check_box:

Parameters: {“commit”=>“Vista mælitæki”,
“authenticity_token”=>“B2u5ULNr7IJ/ta0+hiAMBjmjEtTtc/yMAQQvSxFn2d0=”,
“cats”=>{“flokkur”=>[nil, nil, nil, nil, nil, nil, nil, nil, nil, nil,
nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil]}}

And what does that version of the view code look like?

Best,

Marnen Laibow-Koser
http://www.marnen.org
[email protected]

Hi,
It looks like this now;

<%form_for :cats, :url => {:action => :save_mt} do |form|%>
<[email protected] do |flokkur|%>

<%= form.check_box 'flokkur[]' %> <%= flokkur %>

<%end%> <%= submit_tag "Vista mælitæki", :class => 'submit'%> <%end%>

I’ve tried different parameters for the check_box but to no success…

BR,
Sindri

Finally got it, the empty hash did the trick :wink: Thanks though :slight_smile:

<%form_for :cats, :url => {:action => :save_mt} do |form|%>
<[email protected] do |flokkur|%>

<%= form.check_box flokkur, {}, "yes", "no" %> <%= flokkur %>

<%end%> <%= submit_tag "Vista mælitæki", :class => 'submit'%> <%end%>
10

Marnen Laibow-Koser wrote:

Sindri Guðmundsson wrote:

Marnen Laibow-Koser wrote:

[…]

This is strange code. You’re inside a form_for, so why are you using
check_box_tag rather than check_box ?

I read somewhere that I shouldn’t do it like this, but I couldn’t get
the info on checked/uncecked using check_box. Should I get rid of the
form_for and change the submit button to POST button_to? Why?

No, you should fix the problem that’s preventing you from using
check_box!

Thanks Saurabh P., ofc I should’ve done that, thanks! :slight_smile:

Best,

Marnen Laibow-Koser
http://www.marnen.org
[email protected]

Hi,
I’ve tried that, but I can’t seem to have check_box write anything else
to params[:cats] other than nil. The only thing that happened was that
params[:cats] was an array the same length as the number of categories I
had but only contained nil-objects. Could you please show me how I
should generate the check_boxes inside the loop in my view?

BR,
Sindri