Python 引用插座时出现问题

我似乎在引用我的出口时遇到了问题，在stackoverflow成员的帮助下，我终于实现了拖放操作，但仍然无法让这个出口工作

class controller(NSWindow):


    form_file = IBOutlet()
    mainWindow = IBOutlet()


    #drag and drop ability
    def awakeFromNib(self):
        self.registerForDraggedTypes_([NSFilenamesPboardType, None])
        print 'registerd drag type'


    def draggingEntered_(self, sender):
        print 'dragging entered'
        pboard = sender.draggingPasteboard()
        types = pboard.types()
        opType = NSDragOperationNone
        if NSFilenamesPboardType in types:
            opType = NSDragOperationCopy
        return opType


    def performDragOperation_(self, sender):
        print 'preform drag operation'
        pboard = sender.draggingPasteboard()
        successful = False
        if NSFilenamesPboardType in pboard.types():
            fileAStr = pboard.propertyListForType_(NSFilenamesPboardType)[0].encode('utf-8')
            successful = True

        #edit some things
        print type(fileAStr)
        self.form_file.setStringValue_(fileAStr)
        return successful

我可以删除该文件，但无法从performDragOperation函数内部引用form_文件出口。我想用删除文件中的URL更新NSTextField，但它返回一个非类型错误

这将返回以下内容：

registerd drag type
<type 'NoneType'>
<type 'NoneType'>
2013-01-12 16:32:29.211 app [463:303] formfile = 0x10013c148
2013-01-12 16:32:29.212 app[463:303] mainWindow = 0x10013c148
2013-01-12 16:32:29.212 app[463:303] self = 0x105aba890
<controller: 0x1008a1600>
registerd drag type
<objective-c class NSTextField at 0x7fff785296e8>
<objective-c class controller at 0x10541b6a0>
2013-01-12 16:32:29.216 app[463:303] formfile = 0x105abaa10
2013-01-12 16:32:29.216 app[463:303] mainWindow = 0x105abaa10
2013-01-12 16:32:29.216 app[463:303] self = 0x105aba890
<controller: 0x1008afe00>

但是如果我在Draggingered函数中做同样的测试，那么我只得到一个控制器和一个非类型的对象。问题是它从NIB方法中运行了两次，对吗？我想这可能是我的xib文件的问题，但我已经检查过了，似乎无法找出问题所在

任何想法

---

Tom

由于我不熟悉Python，我的建议可能行得通，也可能行不通

---

如果Python有类，并且您的文件是子类，请尝试在awakeFromNib中调用超类。

从函数中调用超类无法修复函数awakeFromNib被调用两次并产生不同结果的事实。

    print type(self.formfile)
    print type(self.mainWindow)
    NSLog("formfile = %p", self.formfile)
    NSLog("mainWindow = %p", self.mainWindow)
    NSLog("self = %p", self)
    print self

registerd drag type
<type 'NoneType'>
<type 'NoneType'>
2013-01-12 16:32:29.211 app [463:303] formfile = 0x10013c148
2013-01-12 16:32:29.212 app[463:303] mainWindow = 0x10013c148
2013-01-12 16:32:29.212 app[463:303] self = 0x105aba890
<controller: 0x1008a1600>
registerd drag type
<objective-c class NSTextField at 0x7fff785296e8>
<objective-c class controller at 0x10541b6a0>
2013-01-12 16:32:29.216 app[463:303] formfile = 0x105abaa10
2013-01-12 16:32:29.216 app[463:303] mainWindow = 0x105abaa10
2013-01-12 16:32:29.216 app[463:303] self = 0x105aba890
<controller: 0x1008afe00>