从视图中调用模型中的方法

Question

I am trying to evaluate which indicator needs to be displayed next to an item based on if it's been viewed before or not, new comments etc. Until I decide on a symbol to use, I just want a number to display.

in my Report Model i have

def self.indicator
    #bunch of if elsif statements returning a number 0-3
end

in my view i have

<% @reports.each do |report| %>
    <%= report.indicator %>
<% end %>

I get undefined method 'indicator'

I thought I had a grip on how methods work... but clearly not, what am I doing wrong?

Answer 1

Try

def indicator
    #bunch of if elsif statements returning a number 0-3
end

You don't need the self as it [corrected to] is a class level method.

Answer 2

In your view, you are calling an instance method indicator on each report object

report.indicator

But in your model, you have defined a class method. So, to make it work, define your indicator method as an instance method, too:

def indicator
  #bunch of if elsif statements returning a number 0-3
end

Answer 3

Your iteration variable report is used for going through every instance of @reports . With self.indicator you are declaring a class method (via self.name ). So this would make it possible to call Report.indicator . What you want is to call just on a single instance of Report, so you can define the method indicator in your model like this:

def indicator
  #bunch of if elsif statements returning a number 0-3
end

Now this should work!