wxPython/demo/ListCtrl_virtual.py

   1 # 11/20/2003 - Jeff Grimmett (grimmtooth@softhome.net)
   2 #
   3 # o Updated for wx namespace
   4 #
   5 # 11/29/2003 - Jeff Grimmett (grimmtooth@softhome.net)
   6 #
   7 # o wx.ListItem.GetText() returns a wxString pointer, not the text.
   8 #
   9
  10 import  wx
  11 import  images
  12
  13 #----------------------------------------------------------------------
  14
  15 class TestVirtualList(wx.ListCtrl):
  16     def __init__(self, parent, log):
  17         wx.ListCtrl.__init__(
  18             self, parent, -1,
  19             style=wx.LC_REPORT|wx.LC_VIRTUAL|wx.LC_HRULES|wx.LC_VRULES
  20             )
  21
  22         self.log = log
  23
  24         self.il = wx.ImageList(16, 16)
  25         self.idx1 = self.il.Add(images.getSmilesBitmap())
  26         self.SetImageList(self.il, wx.IMAGE_LIST_SMALL)
  27
  28
  29         self.InsertColumn(0, "First")
  30         self.InsertColumn(1, "Second")
  31         self.InsertColumn(2, "Third")
  32         self.SetColumnWidth(0, 175)
  33         self.SetColumnWidth(1, 175)
  34         self.SetColumnWidth(2, 175)
  35
  36         self.SetItemCount(1000000)
  37
  38         self.attr1 = wx.ListItemAttr()
  39         self.attr1.SetBackgroundColour("yellow")
  40
  41         self.attr2 = wx.ListItemAttr()
  42         self.attr2.SetBackgroundColour("light blue")
  43
  44         self.Bind(wx.EVT_LIST_ITEM_SELECTED, self.OnItemSelected)
  45         self.Bind(wx.EVT_LIST_ITEM_ACTIVATED, self.OnItemActivated)
  46         self.Bind(wx.EVT_LIST_ITEM_DESELECTED, self.OnItemDeselected)
  47
  48
  49     def OnItemSelected(self, event):
  50         self.currentItem = event.m_itemIndex
  51         self.log.WriteText('OnItemSelected: "%s", "%s", "%s", "%s"\n' %
  52                            (self.currentItem,
  53                             self.GetItemText(self.currentItem),
  54                             self.getColumnText(self.currentItem, 1),
  55                             self.getColumnText(self.currentItem, 2)))
  56
  57     def OnItemActivated(self, event):
  58         self.currentItem = event.m_itemIndex
  59         self.log.WriteText("OnItemActivated: %s\nTopItem: %s\n" %
  60                            (self.GetItemText(self.currentItem), self.GetTopItem()))
  61
  62     def getColumnText(self, index, col):
  63         item = self.GetItem(index, col)
  64         return item.GetText()
  65
  66     def OnItemDeselected(self, evt):
  67         self.log.WriteText("OnItemDeselected: %s" % evt.m_itemIndex)
  68
  69
  70     #---------------------------------------------------
  71     # These methods are callbacks for implementing the
  72     # "virtualness" of the list...  Normally you would
  73     # determine the text, attributes and/or image based
  74     # on values from some external data source, but for
  75     # this demo we'll just calculate them
  76     def OnGetItemText(self, item, col):
  77         return "Item %d, column %d" % (item, col)
  78
  79     def OnGetItemImage(self, item):
  80         if item % 3 == 0:
  81             return self.idx1
  82         else:
  83             return -1
  84
  85     def OnGetItemAttr(self, item):
  86         if item % 3 == 1:
  87             return self.attr1
  88         elif item % 3 == 2:
  89             return self.attr2
  90         else:
  91             return None
  92
  93
  94 #----------------------------------------------------------------------
  95
  96 def runTest(frame, nb, log):
  97     win = TestVirtualList(nb, log)
  98     return win
  99
 100 #----------------------------------------------------------------------
 101
 102
 103 overview = """\
 104 This example demonstrates the ListCtrl's Virtual List features. A Virtual list
 105 can contain any number of cells, but data is not loaded into the control itself.
 106 It is loaded on demand via virtual methods <code>OnGetItemText(), OnGetItemImage()</code>,
 107 and <code>OnGetItemAttr()</code>. This greatly reduces the amount of memory required
 108 without limiting what can be done with the list control itself.
 109 """
 110
 111
 112
 113 if __name__ == '__main__':
 114     import sys,os
 115     import run
 116     run.main(['', os.path.basename(sys.argv[0])])
 117