Python 向 ObjectListView 复选框创建事件答案

【问题标题】：Python create an event to an ObjectListView check boxPython 向 ObjectListView 复选框创建事件
【发布时间】：2011-04-18 14:17:06
【问题描述】：

当一个框被选中/取消选中时，我将如何创建一个事件？对于这个例子，我只希望它打印关于被检查对象的数据

注意：此代码是从 http://www.blog.pythonlibrary.org/2009/12/23/wxpython-using-objectlistview-instead-of-a-listctrl/ 修改的，作为学习练习

import wx
from ObjectListView import ObjectListView, ColumnDefn

########################################################################
class Book(object):
    """
    Model of the Book object

    Contains the following attributes:
    'ISBN', 'Author', 'Manufacturer', 'Title'
    """
    #----------------------------------------------------------------------
    def __init__(self, title, author, isbn, mfg):
        self.isbn = isbn
        self.author = author
        self.mfg = mfg
        self.title = title


########################################################################
class MainPanel(wx.Panel):
    #----------------------------------------------------------------------
    def __init__(self, parent):
        wx.Panel.__init__(self, parent=parent, id=wx.ID_ANY)
        self.products = [Book("wxPython in Action", "Robin Dunn",
                              "1932394621", "Manning"),
                         Book("Hello World", "Warren and Carter Sande",
                              "1933988495", "Manning")
                         ]

        self.dataOlv = ObjectListView(self, wx.ID_ANY, style=wx.LC_REPORT|wx.SUNKEN_BORDER)
        self.setBooks()
        self.dataOlv.CreateCheckStateColumn()        

        # Allow the cell values to be edited when double-clicked
        self.dataOlv.cellEditMode = ObjectListView.CELLEDIT_SINGLECLICK

        # create an update button
        updateBtn = wx.Button(self, wx.ID_ANY, "Update OLV")
        updateBtn.Bind(wx.EVT_BUTTON, self.updateControl)

        # Create some sizers
        mainSizer = wx.BoxSizer(wx.VERTICAL)

        mainSizer.Add(self.dataOlv, 1, wx.ALL|wx.EXPAND, 5)
        mainSizer.Add(updateBtn, 0, wx.ALL|wx.CENTER, 5)
        self.SetSizer(mainSizer)

    #----------------------------------------------------------------------
    def updateControl(self, event):
        """

        """
        print "updating..."
        product_dict = [Book("Core Python Programming", "Wesley Chun",
                         "0132269937", "Prentice Hall"),
                        Book("Python Programming for the Absolute Beginner",
                         "Michael Dawson", "1598631128", "Course Technology"),
                        Book("Learning Python", "Mark Lutz",
                         "0596513984", "O'Reilly")
                        ]
        data = self.products + product_dict
        self.dataOlv.SetObjects(data)

    #----------------------------------------------------------------------
    def setBooks(self, data=None):
        self.dataOlv.SetColumns([
            ColumnDefn("Title", "left", 220, "title"),
            ColumnDefn("Author", "left", 200, "author"),
            ColumnDefn("ISBN", "right", 100, "isbn"),
            ColumnDefn("Mfg", "left", 180, "mfg")
        ])

        self.dataOlv.SetObjects(self.products)

########################################################################
class MainFrame(wx.Frame):
    #----------------------------------------------------------------------
    def __init__(self):
        wx.Frame.__init__(self, parent=None, id=wx.ID_ANY,
                          title="ObjectListView Demo", size=(800,600))
        panel = MainPanel(self)

########################################################################
class GenApp(wx.App):

    #----------------------------------------------------------------------
    def __init__(self, redirect=False, filename=None):
        wx.App.__init__(self, redirect, filename)

    #----------------------------------------------------------------------
    def OnInit(self):
        # create frame here
        frame = MainFrame()
        frame.Show()
        return True

#----------------------------------------------------------------------
def main():
    """
    Run the demo
    """
    app = GenApp()
    app.MainLoop()

if __name__ == "__main__":
    main()

【问题讨论】：

标签： python events wxpython objectlistview

【解决方案1】：

ObjectListView 类似乎不包含该功能。在挖掘了一段时间的代码后，我决定扩展它。

您可以从ObjectListView 派生您自己的类并强制事件进入。您必须覆盖_HandleLeftDownOnImage 和SetCheckState 方法。或者，您可以根据需要更改 ObjectListView 代码。我派生了一个新类：

import  wx.lib.newevent

OvlCheckEvent, EVT_OVL_CHECK_EVENT = wx.lib.newevent.NewEvent()

class MyOvl(ObjectListView):  
    def SetCheckState(self, modelObject, state):
        """
        This is the same code, just added the event inside
        """
        if self.checkStateColumn is None:
            return None
        else:
            r = self.checkStateColumn.SetCheckState(modelObject, state)

            # Just added the event here ===================================
            e = OvlCheckEvent(object=modelObject, value=state)
            wx.PostEvent(self, e)
            # =============================================================

            return r

    def _HandleLeftDownOnImage(self, rowIndex, subItemIndex):
        """
        This is the same code, just added the event inside
        """
        column = self.columns[subItemIndex]
        if not column.HasCheckState():
            return

        self._PossibleFinishCellEdit()
        modelObject = self.GetObjectAt(rowIndex)
        if modelObject is not None:
            column.SetCheckState(modelObject, not column.GetCheckState(modelObject))

            # Just added the event here ===================================
            e = OvlCheckEvent(object=modelObject, value=column.GetCheckState(modelObject))
            wx.PostEvent(self, e)
            # =============================================================

            self.RefreshIndex(rowIndex, modelObject)

然后我用那个类代替ObjectListView：

self.dataOlv = MyOvl(self, wx.ID_ANY, style=wx.LC_REPORT|wx.SUNKEN_BORDER)

绑定事件：

self.dataOlv.Bind(EVT_OVL_CHECK_EVENT, self.HandleCheckbox)

并写了处理程序：

def HandleCheckbox(self, e):
    print(e.object.title, e.value)

我确信这不是最好的方法，但它是简单有效的 hack :-D。

编辑：完整示例

import wx
import  wx.lib.newevent
from ObjectListView import ObjectListView, ColumnDefn, OLVEvent

OvlCheckEvent, EVT_OVL_CHECK_EVENT = wx.lib.newevent.NewEvent()

class MyOvl(ObjectListView):  
    def SetCheckState(self, modelObject, state):
        """
        This is the same code, just added the event inside
        """
        if self.checkStateColumn is None:
            return None
        else:
            r = self.checkStateColumn.SetCheckState(modelObject, state)

            # Just added the event here ===================================
            e = OvlCheckEvent(object=modelObject, value=state)
            wx.PostEvent(self, e)
            # =============================================================

            return r

    def _HandleLeftDownOnImage(self, rowIndex, subItemIndex):
        """
        This is the same code, just added the event inside
        """
        column = self.columns[subItemIndex]
        if not column.HasCheckState():
            return

        self._PossibleFinishCellEdit()
        modelObject = self.GetObjectAt(rowIndex)
        if modelObject is not None:
            column.SetCheckState(modelObject, not column.GetCheckState(modelObject))

            # Just added the event here ===================================
            e = OvlCheckEvent(object=modelObject, value=column.GetCheckState(modelObject))
            wx.PostEvent(self, e)
            # =============================================================

            self.RefreshIndex(rowIndex, modelObject)

########################################################################
class Book(object):
    """
    Model of the Book object

    Contains the following attributes:
    'ISBN', 'Author', 'Manufacturer', 'Title'
    """
    #----------------------------------------------------------------------
    def __init__(self, title, author, isbn, mfg):
        self.isbn = isbn
        self.author = author
        self.mfg = mfg
        self.title = title

########################################################################
class MainPanel(wx.Panel):
    #----------------------------------------------------------------------
    def __init__(self, parent):
        wx.Panel.__init__(self, parent=parent, id=wx.ID_ANY)
        self.products = [Book("wxPython in Action", "Robin Dunn",
                              "1932394621", "Manning"),
                         Book("Hello World", "Warren and Carter Sande",
                              "1933988495", "Manning")
                         ]

        self.dataOlv = MyOvl(self, wx.ID_ANY, style=wx.LC_REPORT|wx.SUNKEN_BORDER)
        self.setBooks()
        self.dataOlv.CreateCheckStateColumn()
        self.dataOlv.Bind(EVT_OVL_CHECK_EVENT, self.HandleCheckbox)

        # Allow the cell values to be edited when double-clicked
        self.dataOlv.cellEditMode = ObjectListView.CELLEDIT_SINGLECLICK

        # create an update button
        updateBtn = wx.Button(self, wx.ID_ANY, "Update OLV")
        updateBtn.Bind(wx.EVT_BUTTON, self.updateControl)

        # Create some sizers
        mainSizer = wx.BoxSizer(wx.VERTICAL)

        mainSizer.Add(self.dataOlv, 1, wx.ALL|wx.EXPAND, 5)
        mainSizer.Add(updateBtn, 0, wx.ALL|wx.CENTER, 5)
        self.SetSizer(mainSizer)

    def HandleCheckbox(self, e):
        print(e.object.title, e.value)

    #----------------------------------------------------------------------
    def updateControl(self, event):
        """

        """
        print "updating..."
        product_dict = [Book("Core Python Programming", "Wesley Chun",
                         "0132269937", "Prentice Hall"),
                        Book("Python Programming for the Absolute Beginner",
                         "Michael Dawson", "1598631128", "Course Technology"),
                        Book("Learning Python", "Mark Lutz",
                         "0596513984", "O'Reilly")
                        ]
        data = self.products + product_dict
        self.dataOlv.SetObjects(data)

    #----------------------------------------------------------------------
    def setBooks(self, data=None):
        self.dataOlv.SetColumns([
            ColumnDefn("Title", "left", 220, "title"),
            ColumnDefn("Author", "left", 200, "author"),
            ColumnDefn("ISBN", "right", 100, "isbn"),
            ColumnDefn("Mfg", "left", 180, "mfg")
        ])

        self.dataOlv.SetObjects(self.products)

########################################################################
class MainFrame(wx.Frame):
    #----------------------------------------------------------------------
    def __init__(self):
        wx.Frame.__init__(self, parent=None, id=wx.ID_ANY,
                          title="ObjectListView Demo", size=(800,600))
        panel = MainPanel(self)

########################################################################
class GenApp(wx.App):

    #----------------------------------------------------------------------
    def __init__(self, redirect=False, filename=None):
        wx.App.__init__(self, redirect, filename)

    #----------------------------------------------------------------------
    def OnInit(self):
        # create frame here
        frame = MainFrame()
        frame.Show()
        return True

#----------------------------------------------------------------------
def main():
    """
    Run the demo
    """
    app = GenApp()
    app.MainLoop()

if __name__ == "__main__":
    main()

【讨论】：

我是一个非常基础/新级别的用户。您能告诉我如何通过上面的示例应用您的解决方案吗？
@ccwhite1 - 添加了完整的示例。
谢谢，这正是我所需要的

【解决方案2】：

除了以下两个列表之外，ObjectListView 文档似乎没有关于此主题的任何数据：

http://objectlistview.sourceforge.net/python/recipes.html#data-based-checkboxes

http://objectlistview.sourceforge.net/python/recipes.html#how-do-i-use-checkboxes-in-my-objectlistview

第一个可能会通过 checkStateGetter 参数帮助您。我怀疑 ObjectListView 中包含 CheckListCtrlMixin 。如果是这样，那么您可以继承您的 ObjectListView 类并覆盖 OnCheckItem 方法，如 CheckListCtrlMixin 的 wxPython 演示中所示。

我最后的想法是，当您选择行时，您可能必须进行临时事件绑定。我的意思是，在行的选择事件中，尝试获取事件对象（希望是 ListItem 实例）并将该对象绑定到 EVT_CHECKBOX。

如果这些都不起作用，请前往官方 wxPython 邮件列表并在那里询问。这就是大多数 wxPython 用户所在的地方。

【讨论】：