Class: Barby::Outputter

Inherits:
Object
  • Object
show all
Defined in:
lib/barby/outputter.rb

Overview

An Outputter creates something from a barcode. That something can be anything, but is most likely a graphical representation of the barcode. Outputters can register methods on barcodes that will be associated with them.

The basic structure of an outputter class:

class FooOutputter < Barby::Outputter
  register :to_foo
  def to_too
    do_something_with(barcode.encoding)
  end
end

Barcode#to_foo will now be available to all barcodes

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(barcode) ⇒ Outputter

An outputter instance will have access to a Barcode



27
28
29
 
# File 'lib/barby/outputter.rb', line 27

def initialize(barcode)
  self.barcode = barcode
end

Instance Attribute Details

#barcode ⇒ Object

Returns the value of attribute barcode.



23
24
25
 
# File 'lib/barby/outputter.rb', line 23

def barcode
  @barcode
end

Class Method Details

.register(*method_names) ⇒ Object

Register one or more handler methods with this outputter Barcodes will then be able to use these methods to get the output from the outputter. For example, if you have an ImageOutputter, you could do:

register :to_png, :to_gif

You could then do aBarcode.to_png and get the result of that method. The class which registers the method will receive the barcode as the only argument, and the default implementation of initialize puts that into the barcode accessor.

You can also have different method names on the barcode and the outputter by providing a hash:

register :to_png => :create_png, :to_gif => :create_gif



48
49
50
51
52
53
54
55
56
57
58
 
# File 'lib/barby/outputter.rb', line 48

def self.register(*method_names)
  if method_names.first.is_a? Hash
    method_names.first.each do |name, method_name|
      Barcode.register_outputter(name, self, method_name)
    end
  else
    method_names.each do |name|
      Barcode.register_outputter(name, self, name)
    end
  end
end

Instance Method Details

#boolean_groups(reload = false) ⇒ Object

Collects continuous groups of bars and spaces (1 and 0) into arrays where the first item is true or false (1 or 0) and the second is the size of the group

For example, “1100111000” becomes [[true,2],,[true,3],]



93
94
95
96
97
98
99
100
101
102
103
104
105
 
# File 'lib/barby/outputter.rb', line 93

def boolean_groups(reload=false)
  if two_dimensional?
    encoding(reload).map do |line|
      line.scan(/1+|0+/).map do |group|
        [group[0,1] == '1', group.size]
      end
    end
  else
    encoding(reload).scan(/1+|0+/).map do |group|
      [group[0,1] == '1', group.size]
    end
  end
end

#booleans(reload = false) ⇒ Object

Converts the barcode’s encoding (a string containing 1s and 0s) to true and false values (1 == true == “black bar”)

If the barcode is 2D, each line will be converted to an array in the same way



71
72
73
74
75
76
77
 
# File 'lib/barby/outputter.rb', line 71

def booleans(reload=false)#:doc:
  if two_dimensional?
    encoding(reload).map{|l| l.split(//).map{|c| c == '1' } }
  else
    encoding(reload).split(//).map{|c| c == '1' }
  end
end

#encoding(reload = false) ⇒ Object

Returns the barcode’s encoding. The encoding is cached and can be reloaded by passing true



82
83
84
85
 
# File 'lib/barby/outputter.rb', line 82

def encoding(reload=false)#:doc:
  @encoding = barcode.encoding if reload
  @encoding ||= barcode.encoding
end

#two_dimensional? ⇒ Boolean

Returns:

  • (Boolean) 


61
62
63
 
# File 'lib/barby/outputter.rb', line 61

def two_dimensional?
  barcode.respond_to?(:two_dimensional?) && barcode.two_dimensional?
end