Microsoft KB Archive/257495

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Article ID: 257495

Article Last Modified on 8/7/2007



APPLIES TO

  • Microsoft Visual Basic 6.0 Learning Edition
  • Microsoft Visual Basic 6.0 Professional Edition
  • Microsoft Visual Basic 6.0 Enterprise Edition
  • Microsoft Visual Basic 5.0 Control Creation Edition
  • Microsoft Visual Basic 5.0 Learning Edition
  • Microsoft Visual Basic 5.0 Professional Edition
  • Microsoft Visual Basic 5.0 Enterprise Edition



This article was previously published under Q257495

SYMPTOMS

When you click on an item in a ListView control, the ItemClick event for the ListView control executes twice.

CAUSE

This problem is caused by the way in which manual label editing is implemented. When you select an item, the ItemClick event is fired normally, but, in addition, the ListView control enables a built-in timer whose delay is equal to that of the duration of a double-click. When this delay elapses, the timer's event is triggered and the code for this timer determines if the ListView control should enter the label editing mode. If label editing is aborted, which is always the case for manual label editing, then the selection is cleared and re-selected. This re-selection triggers the second ItemClick.

You can cause this problem to occur in one of two ways. The first is to set the LabelEdit property of ListView to lvwManual (as in the sample code in the "More Information" section of this article). An alternate way of reproducing this behavior is to set the LabelEdit property to lvwAutomatic and set Cancel equal to True in the BeforeLabelEdit event of ListView.

RESOLUTION

To resolve this problem, install the latest service pack for Visual Studio 6.0.

If installing the service pack is not an option or you are running a version of Visual Basic earlier than version 6.0, set the LabelEdit property of the ListView control to lvwAutomatic and do not set Cancel equal to True in the in the BeforeLabelEdit event of ListView.

STATUS

Microsoft has confirmed that this is a bug in the Microsoft products that are listed at the beginning of this article. This bug was corrected in the latest service pack for Visual Studio 6.0.

For additional information about Visual Studio service packs, click the following article numbers to view the articles in the Microsoft Knowledge Base:

194022 INFO: Visual Studio 6.0 Service Packs, What, Where, Why

194295 HOWTO: Tell That a Visual Studio Service Pack Is Installed


To download the latest Visual Studio service pack, visit the following Microsoft Web site:

MORE INFORMATION

Steps to Reproduce Behavior

  1. Create a new Standard EXE project in Visual Basic. Form1 is created by default.
  2. From the Project menu, choose Components, select Microsoft Windows Common Controls, and then click OK.
  3. Add a ListView control to Form1.
  4. Paste the following code into Form1's code window:

    Option Explicit
    
    Private Sub Form_Load()
        Dim Col As ColumnHeader
        Dim itmAdd As ListItem
        
        ' Set the report's view
        ListView1.View = lvwReport
        
        ' Add a column to the listview
        Set Col = ListView1.ColumnHeaders.Add(Text:="Items")
        
        ' Set the label editing to manual
        ListView1.LabelEdit = lvwManual
        
        ' Add some sample data
        Set itmAdd = ListView1.ListItems.Add(Text:="one")
        Set itmAdd = ListView1.ListItems.Add(Text:="two")
    End Sub
    
    Private Sub ListView1_ItemClick(ByVal Item As MSComctlLib.ListItem)
        Debug.Print ListView1.SelectedItem.Text
    End Sub
                        
  5. Run the sample.
  6. Click item "two" in the ListView control. This should result in the text of item "two" being displayed in the debug/immediate window.
  7. Wait a moment and then click item "two" again. This results in the text of item "two" being displayed two more times in the debug/immediate window.



Additional query words: sp4

Keywords: kbactivexevents kbbug kbctrl kbfix kblistview kbvs600sp4fix kbvs600sp5fix KB257495