RubyMotion image capturing module

capture_image.rb

# Requires BubbleWrap gem with 'bubble-wrap/camera' required.
module ImageCapture
  # Usage:
  # capture_image({}) do 
  #   # @captured_image should be an instance of UIImage
  # end
  #
  # Options:
  # {
  #   allows_editing: true,
  #   save_photo: true,
  #   media_types: [:image]
  #  }
  #
  # Requires @strings variable to be popluated with the following keys:
  # :take_photo
  # :existing_photo
  # :cancel
  # :photo_save_error

  def capture_image(options = {}, &block)
    @options = {
      allows_editing: true,
      save_photo: true,
      media_types: [:image]
    }.merge(options)
    @callback = block
    @buttons = []

    # Push whatever is available
    @buttons << @strings[:take_photo] if UIImagePickerController.isSourceTypeAvailable(UIImagePickerControllerSourceTypeCamera)
    @buttons << @strings[:existing_photo] if UIImagePickerController.isSourceTypeAvailable(UIImagePickerControllerSourceTypePhotoLibrary)

    #Create actionsheet
    sheet = UIActionSheet.new
    sheet.delegate = self
    @buttons.each do |btn|
      sheet.addButtonWithTitle(btn)
    end
    sheet.cancelButtonIndex = sheet.addButtonWithTitle(@strings[:cancel])
    sheet.showInView(rmq.view_controller.view)
  end

  # UIActionSheet Delegate method
  def actionSheet(sheet, didDismissWithButtonIndex:button_index)
    case @buttons[button_index]
    when @strings[:take_photo]
      BW::Device.camera.rear.picture(@options) do |result|
        @captured_image_result = result
        @captured_image = @options[:allows_editing] == true ? result[:edited_image] : result[:original_image]
        save_photo if @options[:save_photo]
        @callback.call
      end
    when @strings[:existing_photo]
      BW::Device.camera.photo_library.picture(@options) do |result|
        @captured_image_result = result
        @captured_image = @options[:allows_editing] == true ? result[:edited_image] : result[:original_image]
        @callback.call
      end
    end
  end

  # Persist photo to camera roll before we upload
  def save_photo
    UIImageWriteToSavedPhotosAlbum(@captured_image, self, "thisImage:hasBeenSavedInPhotoAlbumWithError:usingContextInfo:", nil)
  end

  def thisImage(image, hasBeenSavedInPhotoAlbumWithError:error, usingContextInfo:ctxInfo)
    App.alert("#{@strings[:photo_save_error]}#{error.localizedDescription}") if error
  end

end