Class: ViewModel

Inherits:

Object

Object
ViewModel

show all

Defined in:: app/models/view_model.rb

Instance Method Summary collapse

#attributes ⇒ Object
#initialize(hash = {}) ⇒ ViewModel constructor

View Model.
#to_hash ⇒ Object (also: #to_h)

Constructor Details

#initialize(hash = {}) ⇒ `ViewModel`

View Model

A View Model is a class that allows you to set an arbitrary hash of attributes and access all values by calling attribute methods.

Examples

model = ViewModel.new(a: 1, b: {b1: 1, b2: 2}, c: 3)

model.a   # => 1
model.b   # => {b1: 1, b2: 2}
model.c   # => 3

Reserved methods or attributes are left untouched. If you want to access an attribute that collides with a reserved method, you can do it via the to_hash method.

model = ViewModel.new(class: "test")

model.class             # => ViewModel
model.to_hash[:class]   # => "test"

# File 'app/models/view_model.rb', line 25

def initialize(hash = {})
  hash.each do |key, value|
    instance_variable_set("@#{key}", value)
  end
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(m, *args, &block) ⇒ `Object` (private)



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# File 'app/models/view_model.rb', line 51

def method_missing(m, *args, &block)
  instance_variable_get("@#{m}")
end

Instance Method Details

#attributes ⇒ `Object`



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# File 'app/models/view_model.rb', line 31

def attributes
  instance_variables.map { |instance_variable| instance_variable.to_s.delete("@").to_sym }
end

#to_hash ⇒ `Object` Also known as: to_h



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# File 'app/models/view_model.rb', line 35

def to_hash
  attributes.map { |attribute| {attribute => value_for(attribute)} }.inject(:merge) || {}
end

Class: ViewModel

Direct Known Subclasses

Instance Method Summary collapse

View Model.

Constructor Details

#initialize(hash = {}) ⇒ ViewModel