1

如果我没有以正确的方式问我的问题，请提前道歉。

试图让这段 Ruby 代码工作。我不明白的是如何让点击在底部调用收益函数（它是一个红绿灯），以便点击将循环通过收益选项。真、假、假将意味着灯是红色的，因为它在顶部，而底部的 2 个是假的。我也很难理解枚举器和产量。

class TrafficLight  
  include Enumerable
  include TL

  def each
    yield [true, false, false]
    yield [true, true, false]
    yield [false, false, true] 
    yield [false, true, false] 
  end
end

class Bulb < Shoes::Shape
  attr_accessor :stack
  attr_accessor :left
  attr_accessor :top
  attr_accessor :switched_on

  def initialize(stack, left, top, switched_on = false)    
    self.stack = stack #don't change. 
    self.left = left    
    self.top = top
    self.switched_on = switched_on
    draw left, top, bulb_colour

  end

  # HINT: Shouldn't need to change this method
  def draw(left, top, colour
    )    
    stack.app do
      fill colour

      stack.append do
        oval left, top, 50
      end
    end
  end

  def bulb_colour 
    "#999999"
  end  
end

class GoBulb < Bulb
  def bulb_colour
    "#00FF30"
  end
end

class WaitBulb < Bulb
  def bulb_colour
    "#FFFC00"
  end
end

class StopBulb < Bulb
  def bulb_colour
    "#FF0000"
  end
end

module TL 
  Go = "#00FF30"
  Wait = "#FFFC00"
  Stop = "#FF0000"
end

Shoes.app :title => "My Amazing Traffic Light", :width => 150, :height => 250 do
  background "000", :curve => 10, :margin => 25  
  stroke black    

  @traffic_light = TrafficLight.new
  @top = StopBulb.new self, 50, 40, true     
  @middle = Bulb.new self, 50, 100, true
  @bottom = Bulb.new self, 50, 160, true


  click do #make this switch on/off depending on what you click. Only 1 should be on 

  end
end

我已经用谷歌搜索并搜索过，但我得到的枚举器示例不允许我做我需要做的事情。非常感谢任何见解。

4

1 回答 1

2

包含当前版本 Shoes 的 Ruby (1.9.1) 在Enumerator#next. 调用此方法时会卡住。因此，您不能迭代地从Enumerator.

必须重写该类TrafficLight以模仿Enumerator#next. 如果没有这样的错误next，我们可以TraficLight.new.cycle在这个循环枚举器上使用并重复调用`next。

module TL 
  Go = "#00FF30"
  Wait = "#FFFC00"
  Stop = "#FF0000"
end

class TrafficLight
  include TL
  STATUS = [
    [true, false, false], 
    [true, true, false], 
    [false, false, true],
    [false, true, false]
  ]
  def initialize; @index = 0; end
  def current
    STATUS[@index % STATUS.size]
  end
  def next
    @index += 1
    current
  end
end

更新Bulb，添加一个update(on)重绘灯泡的方法。

def update(on = false)
  self.switched_on = on
  draw self.left, self.top, on ? self.bulb_colour : '#999999'
end

Shoes.app并更新使用特定灯泡的主要逻辑：

@traffic_light = TrafficLight.new
@top = StopBulb.new self, 50, 40, true     
@middle = WaitBulb.new self, 50, 100, false
@bottom = GoBulb.new self, 50, 160, false

click do #make this switch on/off depending on what you click. Only 1 should be on 
  status = @traffic_light.next
  [@top, @middle, @bottom].zip(status).each do |light, on|
    light.update(on)
  end
end
于 2013-03-28T12:54:13.747 回答