Class: Prawn::ImageHandler

Inherits:
Object
  • Object
show all
Defined in:
lib/prawn/image_handler.rb

Overview

ImageHandler provides a way to register image processors with Prawn.

Extension API collapse

Constructor Details

#initialize ⇒ ImageHandler

Returns a new instance of ImageHandler.



16
17
18
 
# File 'lib/prawn/image_handler.rb', line 16

def initialize
  @handlers = []
end

Instance Method Details

#find(image_blob) ⇒ Object

Find an image handler for an image.

Parameters:

  • image_blob (String)

Returns:

  • (Object)

Raises:



52
53
54
55
56
57
58
59
 
# File 'lib/prawn/image_handler.rb', line 52

def find(image_blob)
  handler = @handlers.find { |h| h.can_render?(image_blob) }

  return handler if handler

  raise Prawn::Errors::UnsupportedImageType,
    'image file is an unrecognised format'
end

#register(handler) ⇒ void

This method returns an undefined value.

Register an image handler.

Parameters:

  • handler (Object) 


24
25
26
27
 
# File 'lib/prawn/image_handler.rb', line 24

def register(handler)
  @handlers.delete(handler)
  @handlers.push(handler)
end

#register!(handler) ⇒ void

This method returns an undefined value.

Register an image handler with the highest priority.

Parameters:

  • handler (Object) 


33
34
35
36
 
# File 'lib/prawn/image_handler.rb', line 33

def register!(handler)
  @handlers.delete(handler)
  @handlers.unshift(handler)
end

#unregister(handler) ⇒ void

This method returns an undefined value.

Unregister an image handler.

Parameters:

  • handler (Object) 


42
43
44
 
# File 'lib/prawn/image_handler.rb', line 42

def unregister(handler)
  @handlers.reject! { |h| h == handler }
end