I'm building an app called "CourseWork to dig into rails/develop my skills and I have a question about how to structure it. Users have a resource called "CourseGrading" that is able to create categories and belongs to "Course". Each "category" should have a name, a percentage out of 100 and a course_id. I need to add these percentages together and alert users if the total isn't 100 while still saving.
Then the user's generated "categories" should populate an enum_string specific to that user in a resource called "CourseAssignment" which has a name, description, category and finalgrade.
Can anyone give hints or resources for how best to accomplish this? Thanks
You probably want to take a look at Active Record Callbacks. These will allow you to insert some code to be run when creating/validating/updating/deleting models.
You should probably make use of the ActiveRecord validations.
Check out this guide that explains how to write your own custom validator. Your custom validator would run when the form gets submitted, and in it, you would grab the percentage params and do your check. If it's not what you expect, you can just add an error to the form and the validation process will just kick the user back to the form page and display the error.
Related
In rails_admin, I have 1 model, for example User and I'm showing the whole user count on the Dashboard statistics.
I would also like to separately show 1 particular column from User on the Dashboard statistics and also able to create, update and delete them.
Is that possible? If yes, may I ask how?
You need to create a new rails admin action replacing the one called dashboard.
Check out how the "controller" looks
https://github.com/sferik/rails_admin/blob/master/lib/rails_admin/config/actions/dashboard.rb
And the view
https://github.com/sferik/rails_admin/blob/master/app/views/rails_admin/main/dashboard.html.haml
A guide on how to create actions
https://github.com/sferik/rails_admin/wiki/Custom-action
What i would do is basically copy paste the files and add the custom column to the main loop iterating on the models.
You'll get the CSS and JS for free if you leave everything else as is.
*I'm not really sure what concept this problem would go under - would this be considered polymorphic associations?
I want to create a system where users can set up triggers so that after a certain event happens, another event happens.
For example, I want the user to be able to define a trigger action as:
"This [Email, Document] must be sent to all users after they [Sign up, read email A, sign document B]."
As you can see within the brackets "[]", the conditions can be tied to various objects and actions.
My thought was to create a model TriggerCondition and storing columns
:object_id, :assigned_to, :activated_when
but the object_id(Email, Document) can be different models.
Would adding a column :object_type that can be either email or document be the best solution? Or is there a more sophisticated way of designing so that I can pass in an object and it will automatically know what I'm referring to?
Regarding the :activated_when condition, I'm completely unsure how I would store and check for condition. Would I be able to use a syntax similar to "Email#marked_as_read(A)?"
I'm trying to use Rails Observers to trigger the action
http://api.rubyonrails.org/v3.2.13/classes/ActiveRecord/Observer.html
Rails is built to handle polymorphic associations just like this.
I'm making an application that involves booking appointments for users. I have a User model and an AvailableDate model. The user has_many availble_dates and the AvailableDate belongs_to user.
I want to present a form for the user so that they can mark a couple of dates in a calendar and each of the dates they mark will become an AvailableDate object tied to that user.
At the moment my solution is to do all the work that a form_for helper would normally do manually. This involves a lot of javascript and is generally just getting far too messy.
I can't figure out how I should make a form_for tag work when I need to create potentially infinitely many dates. In theory a user could keep marking off dates in the future as available. If I knew how many dates I needed to create for a user, I could do user.available_dates.build, N times. But this doesn't work here.
Can anyone help? It like this problem should be pretty common. Am I designing my application wrong?
One technique is to render the fields for your association once, outside the form.
When the user performs whatever interaction that should create a new set of inputs you use javascript to clone the initial set of fields and insert them into the form. The one thing you need to do is change the name of these inputs so that they are unique. Usually people use the current time in milliseconds for this unique identifier.
Been there & have found several resources to help: Tutorial & Cocoon
The bottom line is you need to ensure child_index is unique for each field. The tutorial I use has child_index: Time.now.to_i to create a truly unique id, consequently allowing you to add as many fields as you want
The best way to do this:
Render fields_for as a partial (passing your form builder object)
When you want to add new field, create ajax_field action
Make ajax_field view have its own form_builder
Both your original & ajax_field forms will call the partial
On front-end, you can use JS to GET new form action & append field to page
I can give you code if you want
I'm not sure what's the best approach in my situation, I would like an opinion.
My situation is:
I have a "Ticket" model, having several fields of many kinds: text, numerical and associations. Tickets support comments through the acts_as_commentable gem.
The tickets are generated by users, who can comment and modify their own tickets.
Because the fields of a ticket can change over time I would like to allow my users to modify several of them. What I need though is to keep a commented history of all the changes, so that at any moment they can see in a ticket what, why and when was changed, in the comment, timestamp and list of changes that they can see together with the comment.
I was thinking to solve this by generating a "TicketUpdate" model, have the TicketUpdates generated in the Comments form (using fields_for and accepts_nested_attributes_for).
Basically the user could select in a drop down list (i.e. a select tag) the field they want to change, changing the value of the drop down would trigger an event to show an appropriate input field (input for the text and numeric fields, select for the associations) with the old value pre-populated
I could intercept the TicketUpdates in the "comment/create" controller performing the updates.
This approach would look nice and sweet to the user, but I don't see how to implement in a neat or DRY way.
Because ticket has many fields and they are mixed decimals and associations, I would have to implement specific logic for each field, both in the view and in the controller.
I'm not sure if there's maybe a better approach, or there's actually any gem or trick to get this done easily.
anyone got anything to recommend me here?
I'm using rails 3.2.8.
I have been trying to analyze this problem very closely but I am still yet to find a good way to approach it. (Hope my explanation is good enough)
So I have three models [user, status and milestone]
the status model belongs to the user model
The milestone model belongs to status model and also to the user model through the status model
Okay so I want to tie each milestone to a model by doing something like (milestone.build_status, this is pretty easy from the CLI, I have tested and tried it, and it works as expected.)
So the big issue I am having is on the web page. I am displaying all the statuses (I have already handled cases when the user enter a status) to user with a corresponding text field where they can enter their milestone, well when I do I post I can only get the params of the text field that was supplied (duh! isnt that obvious).
My question would be what are some possible approaches that I can use to figure which particular status that the user entered the milestone for.
I think you may be looking for Active Record Nested Attributes
This will allow your forms for your object of the User model to also accept input for its associated Status and/or Milestone objects for creating and updating each associated records all in one transaction.