comboctrl.py

用wxPython编写GUI程序的样例代码

import wx
import wx.combo
import os

#----------------------------------------------------------------------

class NullLog:
    def write(*args):
        pass


# This class is used to provide an interface between a ComboCtrl and a
# ListCtrl that is used as the popoup for the combo widget.  In this
# case we use multiple inheritance to derive from both wx.ListCtrl and
# wx.ComboPopup, but it also works well when deriving from just
# ComboPopup and using a has-a relationship with the popup control,
# you just need to be sure to return the control itself from the
# GetControl method.

class ListCtrlComboPopup(wx.ListCtrl, wx.combo.ComboPopup):
        
    def __init__(self, log=None):
        if log:
            self.log = log
        else:
            self.log = NullLog()
            
        
        # Since we are using multiple inheritance, and don't know yet
        # which window is to be the parent, we'll do 2-phase create of
        # the ListCtrl instead, and call its Create method later in
        # our Create method.  (See Create below.)
        self.PostCreate(wx.PreListCtrl())

        # Also init the ComboPopup base class.
        wx.combo.ComboPopup.__init__(self)
        

    def AddItem(self, txt):
        self.InsertStringItem(self.GetItemCount(), txt)

    def OnMotion(self, evt):
        item, flags = self.HitTest(evt.GetPosition())
        if item >= 0:
            self.Select(item)
            self.curitem = item

    def OnLeftDown(self, evt):
        self.value = self.curitem
        self.Dismiss()


    # The following methods are those that are overridable from the
    # ComboPopup base class.  Most of them are not required, but all
    # are shown here for demonstration purposes.


    # This is called immediately after construction finishes.  You can
    # use self.GetCombo if needed to get to the ComboCtrl instance.
    def Init(self):
        self.log.write("ListCtrlComboPopup.Init")
        self.value = -1
        self.curitem = -1


    # Create the popup child control.  Return true for success.
    def Create(self, parent):
        self.log.write("ListCtrlComboPopup.Create")
        wx.ListCtrl.Create(self, parent,
                           style=wx.LC_LIST|wx.LC_SINGLE_SEL|wx.SIMPLE_BORDER)
        self.Bind(wx.EVT_MOTION, self.OnMotion)
        self.Bind(wx.EVT_LEFT_DOWN, self.OnLeftDown)
        return True


    # Return the widget that is to be used for the popup
    def GetControl(self):
        #self.log.write("ListCtrlComboPopup.GetControl")
        return self

    # Called just prior to displaying the popup, you can use it to
    # 'select' the current item.
    def SetStringValue(self, val):
        self.log.write("ListCtrlComboPopup.SetStringValue")
        idx = self.FindItem(-1, val)
        if idx != wx.NOT_FOUND:
            self.Select(idx)

    # Return a string representation of the current item.
    def GetStringValue(self):
        self.log.write("ListCtrlComboPopup.GetStringValue")
        if self.value >= 0:
            return self.GetItemText(self.value)
        return ""

    # Called immediately after the popup is shown
    def OnPopup(self):
        self.log.write("ListCtrlComboPopup.OnPopup")
        wx.combo.ComboPopup.OnPopup(self)

    # Called when popup is dismissed
    def OnDismiss(self):
        self.log.write("ListCtrlComboPopup.OnDismiss")
        wx.combo.ComboPopup.OnDismiss(self)

    # This is called to custom paint in the combo control itself
    # (ie. not the popup).  Default implementation draws value as
    # string.
    def PaintComboControl(self, dc, rect):
        self.log.write("ListCtrlComboPopup.PaintComboControl")
        wx.combo.ComboPopup.PaintComboControl(self, dc, rect)

    # Receives key events from the parent ComboCtrl.  Events not
    # handled should be skipped, as usual.
    def OnComboKeyEvent(self, event):
        self.log.write("ListCtrlComboPopup.OnComboKeyEvent")
        wx.combo.ComboPopup.OnComboKeyEvent(self, event)

    # Implement if you need to support special action when user
    # double-clicks on the parent wxComboCtrl.
    def OnComboDoubleClick(self):
        self.log.write("ListCtrlComboPopup.OnComboDoubleClick")
        wx.combo.ComboPopup.OnComboDoubleClick(self)

    # Return final size of popup. Called on every popup, just prior to OnPopup.
    # minWidth = preferred minimum width for window
    # prefHeight = preferred height. Only applies if > 0,
    # maxHeight = max height for window, as limited by screen size
    #   and should only be rounded down, if necessary.
    def GetAdjustedSize(self, minWidth, prefHeight, maxHeight):
        self.log.write("ListCtrlComboPopup.GetAdjustedSize: %d, %d, %d" % (minWidth, prefHeight, maxHeight))
        return wx.combo.ComboPopup.GetAdjustedSize(self, minWidth, prefHeight, maxHeight)

    # Return true if you want delay the call to Create until the popup
    # is shown for the first time. It is more efficient, but note that
    # it is often more convenient to have the control created
    # immediately.    
    # Default returns false.
    def LazyCreate(self):
        self.log.write("ListCtrlComboPopup.LazyCreate")
        return wx.combo.ComboPopup.LazyCreate(self)
        


#----------------------------------------------------------------------
# This class is a popup containing a TreeCtrl.  This time we'll use a
# has-a style (instead of is-a like above.)

class TreeCtrlComboPopup(wx.combo.ComboPopup):

    # overridden ComboPopup methods
    
    def Init(self):
        self.value = None
        self.curitem = None

        
    def Create(self, parent):
        self.tree = wx.TreeCtrl(parent, style=wx.TR_HIDE_ROOT
                                |wx.TR_HAS_BUTTONS
                                |wx.TR_SINGLE
                                |wx.TR_LINES_AT_ROOT
                                |wx.SIMPLE_BORDER)
        self.tree.Bind(wx.EVT_MOTION, self.OnMotion)
        self.tree.Bind(wx.EVT_LEFT_DOWN, self.OnLeftDown)
        

    def GetControl(self):
        return self.tree


    def GetStringValue(self):
        if self.value:
            return self.tree.GetItemText(self.value)
        return ""


    def OnPopup(self):
        if self.value:
            self.tree.EnsureVisible(self.value)
            self.tree.SelectItem(self.value)


    def SetStringValue(self, value):
        # this assumes that item strings are unique...
        root = self.tree.GetRootItem()
        if not root:
            return
        found = self.FindItem(root, value)
        if found:
            self.value = found
            self.tree.SelectItem(found)


    def GetAdjustedSize(self, minWidth, prefHeight, maxHeight):
        return wx.Size(minWidth, min(200, maxHeight))
                       

    # helpers
    
    def FindItem(self, parentItem, text):        
        item, cookie = self.tree.GetFirstChild(parentItem)
        while item:
            if self.tree.GetItemText(item) == text:
                return item
            if self.tree.ItemHasChildren(item):
                item = self.FindItem(item, text)
            item, cookie = self.tree.GetNextChild(parentItem, cookie)
        return wx.TreeItemId();


    def AddItem(self, value, parent=None):
        if not parent:
            root = self.tree.GetRootItem()
            if not root:
                root = self.tree.AddRoot("<hidden root>")
            parent = root

        item = self.tree.AppendItem(parent, value)
        return item

    
    def OnMotion(self, evt):
        # have the selection follow the mouse, like in a real combobox
        item, flags = self.tree.HitTest(evt.GetPosition())
        if item and flags & wx.TREE_HITTEST_ONITEMLABEL:
            self.tree.SelectItem(item)
            self.curitem = item
        evt.Skip()


    def OnLeftDown(self, evt):
        # do the combobox selection
        item, flags = self.tree.HitTest(evt.GetPosition())
        if item and flags & wx.TREE_HITTEST_ONITEMLABEL:
            self.curitem = item
            self.value = item