Sorry, this may seem like a simple issue, but: I have a collection_select element that is called via ajax from a _updateregions.html.erb file for creating and editing records that looks like:
<%= collection_select(:wine, :wineregionid, regions, :wineregionid, :regionname,
options = {:selected => :wineregionid, :prompt => "Select a Region"}
) %>
The problem is, when editing an existing record, the prompt is appearing by default instead on the records value. When I remove the :prompt, it works fine... question is, how can I make this work for both the New and Edit case?
According to http://api.rubyonrails.org/classes/ActionView/Helpers/FormOptionsHelper.html I think I'm doing it right....
collection_select(object, method,
collection, value_method, text_method,
options = {}, html_options = {})
Returns and tags for
the collection of existing return
values of method for object‘s class.
The value returned from calling method
on the instance object will be
selected. If calling method returns
nil, no selection is made without
including :prompt or :include_blank in
the options hash.
i think :prompt donot takes a string .
it should be true/false or null.
try this
<%= collection_select(:wine, :wineregionid, regions, :wineregionid, :regionname,
options = {:selected => :wineregionid, :prompt => true) %>
Related
I want to limit the entry possibilities for a text field in my model to a previously defined array.
How do I make an options_for_select with just a 1-dimensional array like ["foo","bar","foobar"]?
I tried
form_for #mappings do |f|
f.select(:mapping_type, options_for_select(["foo","bar","foobar"]), class: "..."
end
But the select box comes out all messed up like this:
<select name="section_mapping[mapping_type]" id="section_mapping_mapping_type">
as opposed to what it should be:
<select name="mapping_type" >
EDIT:
I changed the f.select to select_tag and the form shows up without any errors but when I submit it, it leaves that field empty
EDIT 2:
f.collection_select(:mapping_type, options_for_select([...]), class: "..."
works as in it submits the form with the value correctly, but the HTML class is not applied. Why is that?
Basically, you want to be able to tie your collection select to a property of the object (in your case, #mappings)
Also, from the doc on rails collection_select, it will take options as follow:
collection_select(object, method, collection, value_method, text_method, options = {}, html_options = {}) public
Objet: the object you are binding the selected option to (#mappings [f]) in this case
method: The property/attribute of the object (in this case, mapping_type)
collection: The collection for select ( ["foo","bar","foobar"] )
value_method: The value you want to send back with the submit (Note that this is a method which means you should be able to call it on an object.) more on this later.
text_method: The value you want to show as text on the select option on the view (this is also a method as above, more on this later as well)
options: any additional option you want, (e.g: include_blank)
html_options: eg: id, class etc.
As concerning the value_method and text_method, these are methods that should be called on your collection, which means that your collection will be an array of objects.
To this end, you can have the following:
class CollectionArr
include ActiveModel::Model
attr_accessor :name
ARR = [
{"name" => "foo"},
{"name" => "bar"},
{"name" => "foobar"}
]
def self.get_collection
ARR.collect do |hash|
self.new(
name: hash['name']
)
end
end
end
From here, calling CollectionArr.get_collection will return an array of objects where you can cal .name to return either foo, bar, or foobar. This makes using the collection_select and easy deal from here:
<%= f.collection_select : mapping_type, CollectionArr.get_collection, :name, :name, {:include_blank => "Select one"} %>
And all is green...
So I was experiencing an error when I was attaching a collection_select to my form_for object like so:
<%= f.collection_select(:city_id, #cities, :id, :name, {:prompt => "Select a City"}, {:id => 'cities_select', multiple: true}) %>
and getting the error:
undefined local variable 'city_id'
But when I don't bind the select like so:
<%= collection_select(nil, :city_id, #cities, :id, :name, {:prompt => "Select a City"}, {:id => 'cities_select', multiple: true}) %>
It works fine.
I just want to understand the theory behind why one works and the other doesn't?
I think what's tripping you up, primarily, is the concepts you have of what's going on here.
Nothing is “binding” anything to anything by calling a method on a form helper object. There are form helper methods, like collection_select, that can be used to build HTML elements. There are form builders that have methods, like collection_select that build HTML form elements for a form tied to an object.
The issue you're having here is that the FormOptionsHelper#collection_select method and the FormBuilder#collection_select method are not the same method and do not accept the same arguments:
FormOptionsHelper#collection_select vs FormBuilder#collection_select
Pay particular attention to the arguments provided. It's also worth noticing that FormBuilder essentially delegates this work to the template (i.e. FormOptionsHelper) and adjusts the arguments as needed.
Is it possible to somehow use the :selected option that you'd use on a normal select view helper with the grouped_collection_select function? I'd like to set the value that gets pre-selected in my list. I've tried passing in :selected as an option with no luck!
Here's some code snippts of my tests:
grouped_collection_select 'user[subscription_attributes]', :subscription_plan_id, Trade.order(:name).all, :subscription_plans, :name, :id, :display_name, { :include_blank => true, :selected => 5 }
grouped_collection_select 'user[subscription_attributes]', :subscription_plan_id, Trade.order(:name).all, :subscription_plans, :name, :id, :display_name, :include_blank => true, :selected => 5
Neither version works. No selected is set. I'm using this to set a value for a nested model. I'm using the railscasts dynamic select list methods: http://railscasts.com/episodes/88-dynamic-select-menus-revised
I couldn't get formtastic to play nicely with the group selects so I had to do it by hand but I don't keep this value selected when a user fails validations. I'd like to keep this set when they fix validation errors.
I just ran across the same problem and solved it using the option_groups_from_collection_for_select helper and the select helper documented at: http://api.rubyonrails.org/classes/ActionView/Helpers/FormOptionsHelper.html.
The first step is to create the grouped options. Taking your example, it should look like:
<% options = option_groups_from_collection_for_select(Trade.order(:name).all,
:subscription_plans, :name, :id, :display_name, 5) %>
Then I created the select object like:
<%= select('user[subscription_attributes]', :subscription_plan_id, options,
include_blank: true) %>
You could write it all out in one line, I just broke out the options into a separate variable to illustrate the two different methods.
Maybe too late, but the API documentation of grouped_collection_select states:
'The value returned from calling method on the instance object will be selected.'
So, you don't even have to specify a :selected option, since Rails will automatically select based on the current value of your attribute.
If subscription_plan_id has value 5, then that's what will be selected.
If that's supposed to be a default value, then you can set it with an after_initialize in your model.
Actually you need to send in options include_blank for example
<%= grouped_collection_select :id, model.all, options = {:include_blank => 'Selecione'}%>
In my rails app, i have a drop down box where i retrieve all groups from the Group table and display them using the collection_select tag.
When the user selects 'None', I want to pass '0' as option value.
Currently, an empty string is passed.
Is there a way to include option value = 0 for 'None'?
<%= f.collection_select :SUB_GROUP, Group.all, :Group_ID, :Group_ID, :include_blank => 'None' %>
Many many thanks for any suggestion provided
If you use options_for_select in combination with select_tag you can achieve that using this:
options_for_select(
[['None', '0']].concat(
Group.all.collect { |g| [g.group_id.to_s, g.group_id.to_s] }
)
)
In order to keep your views uncluttered, you might want to generalize and move this into a helper method with a reasonable name.
I have a Rails 2.3 web application that uses the collection_select helper with :multiple => true to handle a habtm relationship. This is working fine to set one or multiple values, however I have not figured out how to allow to REMOVE all selections.
Code:
<%= f.collection_select :category_ids, Category.find(:all), :id, :name,
{ :selected => #entry.category_ids },
{ :multiple => true, :name => 'entry[category_ids][]' }
%>
Once the user has ever set a category for an entry, how would I go about allowing it to be removed, so that this entry has no category? Is this possible with collection_select or would I need to add a checkbox to handle this specially?
P.S: I already tried with :prompt, :include_blank and :allow_blank, but as far as I could see neither of them did anything.
In your controller's update action, put in the following line:
params[:entry][:category_ids] ||= []
before the call to Entry.find.