Chingu::GameWindow 上的 Chingu 输入属性导致异常

Question

这段代码在 Chingu 中导致了一个非常奇怪的异常，这是一个依赖于 Gosu 2D 游戏框架的 ruby​​ 游戏库：

class StopSignAttack < Chingu::Window

  def initialize
    super(1000, 1000, false)
    self.input = { :escape => :close }
    self.caption = "Stop Sign ATTACK!!!"
    push_game_state(Start.new)
  end

end

Chingu::Window 的 input 属性的值应该只是让游戏窗口在按下退出键时关闭。按下退出键时窗口会关闭，但会出现以下异常：

/Users/sams/.rvm/gems/ruby-1.9.3-p0/gems/chingu-0.8.1/lib/chingu/helpers/input_dispatcher.rb:63:in `block in dispatch_input_for': undefined method `button_down?' for nil:NilClass (NoMethodError)
    from /Users/sams/.rvm/gems/ruby-1.9.3-p0/gems/chingu-0.8.1/lib/chingu/helpers/input_dispatcher.rb:62:in `each'
    from /Users/sams/.rvm/gems/ruby-1.9.3-p0/gems/chingu-0.8.1/lib/chingu/helpers/input_dispatcher.rb:62:in `dispatch_input_for'
    from /Users/sams/.rvm/gems/ruby-1.9.3-p0/gems/chingu-0.8.1/lib/chingu/window.rb:148:in `block in intermediate_update'
    from /Users/sams/.rvm/gems/ruby-1.9.3-p0/gems/chingu-0.8.1/lib/chingu/window.rb:148:in `each'
    from /Users/sams/.rvm/gems/ruby-1.9.3-p0/gems/chingu-0.8.1/lib/chingu/window.rb:148:in `intermediate_update'
    from /Users/sams/.rvm/gems/ruby-1.9.3-p0/gems/chingu-0.8.1/lib/chingu/window.rb:133:in `update'
    from stop_sign_attack.rb:24:in `<main>'

我试过在Chingu::Window中实现close方法，调用超类close方法：

  def close
    super.close
  end

按 ESC 键时出现此异常：

stop_sign_attack.rb:23:in `close': undefined method `close' for nil:NilClass (NoMethodError)
    from /Users/sams/.rvm/gems/ruby-1.9.3-p0/gems/gosu-0.7.41-universal-darwin/lib/gosu/swig_patches.rb:19:in `rescue in block (2 levels) in <class:Window>'
    from /Users/sams/.rvm/gems/ruby-1.9.3-p0/gems/gosu-0.7.41-universal-darwin/lib/gosu/swig_patches.rb:12:in `block (2 levels) in <class:Window>'
    from /Users/sams/.rvm/gems/ruby-1.9.3-p0/gems/gosu-0.7.41-universal-darwin/lib/gosu/swig_patches.rb:26:in `show'
    from /Users/sams/.rvm/gems/ruby-1.9.3-p0/gems/gosu-0.7.41-universal-darwin/lib/gosu/swig_patches.rb:26:in `show'
    from stop_sign_attack.rb:28:in `<main>'

感谢任何想法。

Answer 1

您遗漏了一些允许他人调试的信息。例如，您正在推送一个名为 Start 的游戏状态，但您的示例中没有声明 Start 类。但你还没有分享那部分代码。我创建了以下示例项目来测试你在那里得到了什么：

require 'chingu'

# A simple GameState-example
class Start < Chingu::GameState
end

class StopSignAttack < Chingu::Window

  def initialize
    super(1000, 1000, false)
    self.input = { :escape => :close }
    self.caption = "Stop Sign ATTACK!!!"
    push_game_state(Start.new)
  end

end

StopSignAttack.new.show

这工作得很好，当我按下退出时，没有任何异常退出。