我在访问一个类变量（Qt::Action 数组）时遇到了分段错误的问题，我一直在尝试精简代码以复现这个问题：
#!/usr/bin/ruby
require 'Qt4'
require 'rufus/scheduler'
app = Qt::Application.new(ARGV)
class ManagerWidget < Qt::Widget
signals 'changed(int)'
def initialize
super(nil)
max_index = 2
next_index = 0
scheduler = Rufus::Scheduler.start_new
scheduler.every '10s' do
emit changed(next_index)
if next_index < max_index - 1
next_index += 1
else
next_index = 0
end
end
end
end
class Tray < Qt::Widget
def initialize
super(nil)
tray = Qt::SystemTrayIcon.new
manager_widget = ManagerWidget.new
menu = Qt::Menu.new
tray_icon = Qt::Icon.new("./icons/Gnome-Preferences-Desktop-Wallpaper-64.png")
actions = []
manager_widget.connect(SIGNAL('changed(int)')) do |i|
puts "changed #{i}"
actions[i].text = '...' if actions && actions[i]
end
2.times do |i|
sub_menu = Qt::Menu.new("#{i + 1}")
actions[i] = sub_menu.add_action('x')
menu.add_menu(sub_menu)
end
tray.icon = tray_icon
tray.context_menu = menu
tray.show
end
end
Tray.new
app.exec
上面的代码输出：
"sni-qt/12147" WARN 14:35:48.326 void StatusNotifierItemFactory::connectToSnw() Invalid interface to SNW_SERVICE
changed 0
changed 1
changed 0
changed 1
changed 0
changed 1
changed 0
changed 1
./min-code-example.rb:42: [BUG] Segmentation fault
ruby 1.9.3p0 (2011-10-30 revision 33570) [x86_64-linux]
[... snipped due to character limits on posting ...]
[NOTE]
You may have encountered a bug in the Ruby interpreter or extension libraries.
Bug reports are welcome.
For details: http://www.ruby-lang.org/bugreport.html
Aborted (core dumped)
Failed (134)
似乎需要使用子菜单来触发此问题 - 至少将操作添加到托盘菜单本身可以运行相当长的时间而没有问题（我让它运行了比上面的代码出错所需的时间长10倍以上）。
Ruby版本：
ruby 1.9.3p0 (2011-10-30 revision 33570) [x86_64-linux]
Qt版本：4.8.1
绑定版本：qtbindings (4.8.3.0)
Linux版本：Ubuntu 12.04
另一个奇怪的行为是，puts调用的输出有时会立即显示在控制台中，而其他时候只有在我将鼠标悬停在托盘图标上时才会打印出来。我甚至不确定从何处开始追踪这个问题，因此非常感谢您提供的任何意见。
更新：由于无法进一步进行，我已经放置了一段时间。我试图重新开始解决这个问题，但我仍然遇到了同样的问题。我深入研究了一下问题，因为它说“missing_method”，所以我首先打印类来确保我确实在查看Qt :: Action（我是），然后查看哪些方法根据
actions [0] .methods 可用。[:setShortcut, :shortcut=, :qobject_cast, :inspect, :pretty_print, :className,
:class_name, :inherits, :findChildren, :find_children, :findChild, :find_child,
:connect, :method_missing, :const_missing, :dispose, :isDisposed, :disposed?,
:qVariantValue, :qVariantFromValue, :**, :+, :~, :-@, :-, :*, :/, :%, :>>,
:<<, :&, :^, :|, :<, :<=, :>, :>=, :==, :is_a?, :kind_of?, :methods,
:protected_methods, :public_methods, :singleton_methods, :qDebug, :qFatal,
:qWarning, :SIGNAL, :SLOT, :emit, :QT_TR_NOOP, :QT_TRANSLATE_NOOP, :nil?, :===,
:=~, :!~, :eql?, :hash, :<=>, :class, :singleton_class, :clone, :dup,
:initialize_dup, :initialize_clone, :taint, :tainted?, :untaint, :untrust,
:untrusted?, :trust, :freeze, :frozen?, :to_s, :private_methods,
:instance_variables, :instance_variable_get, :instance_variable_set,
:instance_variable_defined?, :instance_of?, :tap, :send, :public_send,
:respond_to?, :respond_to_missing?, :extend, :display, :method, :public_method,
:define_singleton_method, :object_id, :to_enum, :enum_for, :equal?, :!, :!=,
:instance_eval, :instance_exec, :__send__, :__id__, "blockSignals", "children",
"connect", "deleteLater", "disconnect", "dumpObjectInfo", "dumpObjectTree",
"dynamicPropertyNames", "event", "eventFilter", "inherits", "installEventFilter",
"widgetType?", "killTimer", "metaObject", "moveToThread", "objectName", "parent",
"property", "qt_metacall", "qt_metacast", "removeEventFilter", "objectName=",
"parent=", "setProperty", "setUserData", "signalsBlocked", "startTimer",
"thread", "userData", "actionGroup", "activate", "associatedGraphicsWidgets",
"associatedWidgets", "autoRepeat", "data", "font", "hover", "icon", "iconText",
"checkable?", "checked?", "enabled?", "iconVisibleInMenu?", "separator?",
"visible?", "menu", "menuRole", "parentWidget", "priority", "actionGroup=",
"autoRepeat=", "checkable=", "checked=", "data=", "disabled=", "enabled=",
"font=", "icon=", "iconText=", "iconVisibleInMenu=", "menu=", "menuRole=",
"priority=", "separator=", "shortcut=", "shortcutContext=", "shortcuts=",
"softKeyRole=", "statusTip=", "text=", "toolTip=", "visible=", "whatsThis=",
"shortcut", "shortcutContext", "shortcuts", "showStatusText", "softKeyRole",
"statusTip", "text", "toggle", "toolTip", "trigger", "whatsThis"]
在这种情况下，我尝试执行
actions[0].enabled = true时发生了段错误，据我理解（从底部第6行开始，enabled=），这也在输出中。我还尝试过setEnabled(true)、set_enabled(true)和其他我能想到的任何方法。即使在最初将操作放入数组的循环内部执行
inspect操作也会导致段错误。我真的不知道出了什么问题。编辑：针对使用
QTimer的建议，我尝试了一下，但仍然遇到了同样的问题。目前的代码比上面列出的要复杂得多，因此我将在此处编写一些快速的伪代码来说明流程：def init_tray
actions = []
2.times do |i|
actions[i] = ... # init and add to systray, store reference in array
end
update = Proc.new do |i|
actions[i].setText('...') # update the text on one of the actions defined above
end
listener = ... # create a listener that can be called by Manager on certain events - will call the update Proc among other things.
manager = Manager.new(..., listener)
end
调用Manager.new初始化该对象并在最后调用监听器以进行状态更改，这反过来调用update Proc，该Proc访问actions数组。此时应该都在同一个线程中，除了实际创建Qt::Action的操作外，这些行都不依赖于QT。我已经删除了Rufus调度并使用QTimer代替，但它根本没有足够远，不能成为问题的原因。
emit，你可能需要使用类似于QTimer而不是Rufus的东西。 - Casperinitialize方法被执行了两次。我不知道是什么原因导致了这种情况，也不知道为什么会这样。我肯定在自己的代码中找不到任何参考。 - Vala