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禁用VB.NET 2008 Winform Listview中的复选框选择

listview .net-3.5 visual-studio-2008 winforms vb.net

JFV · 技术社区 · 17 年前

例如:我有一个计时器,它根据选中的Listview项启动备份。经过一段时间后,我不希望最终用户能够单击listview中的任何复选框(因此我有一组要备份的项目),但我希望他们能够在执行备份时滚动列表。我试过这个:

Private Sub clboxOptions_ItemChecked(ByVal sender As System.Object, ByVal e As System.Windows.Forms.ItemCheckedEventArgs) Handles clboxOptions.ItemChecked

If backupStarted = True Then
   If e.Item.Checked = True Then
      e.Item.Checked = False
   Else
      e.Item.Checked = True
End If

JFV

5 回复 | 直到 17 年前

GatewayToCode 9 年前

下面是禁用用户单击listviewitem复选框的另一种方法。

 Public Sub ChangeItemCheckState(ByVal val As Boolean, ByVal index As Integer)
    If Monitor.TryEnter(Me.Items(index), 10) Then
        Try
            Me.Items(index).Checked = val

        Finally
            Monitor.Exit(Me.Items(index))
        End Try
    End If
End Sub

Public Sub ChangeItemCheckState(ByVal val As Boolean, ByVal item As ListViewItem)
    If Monitor.TryEnter(item, 10) Then
        Try
            item.Checked = val
        Finally
            Monitor.Exit(item)
        End Try
    End If
End Sub

Private Sub ListviewOPC_ItemCheck(sender As Object, e As ItemCheckEventArgs) Handles Me.ItemCheck
    If Monitor.IsEntered(Me.Items(e.Index)) Then
        '
    Else
        'prevent click from users
        e.NewValue = e.CurrentValue
    End If
End Sub

此方法是线程安全的。要更改项目的checkedstate,必须调用ChangeItemCheckState方法。如果要通过单击启用/禁用itemcheck,则必须添加另一个属性。

Private disableUserCheckItem As Boolean
Public Property PreventUserCheckItem() As Boolean
    Get
        Return disableUserCheckItem
    End Get
    Set(ByVal value As Boolean)
        disableUserCheckItem = value
    End Set
End Property

 Public Sub ChangeItemCheckState(ByVal val As Boolean, ByVal index As Integer)
    If Monitor.TryEnter(Me.Items(index), 10) Then
        Try
            Me.Items(index).Checked = val
        Finally
            Monitor.Exit(Me.Items(index))
        End Try
    End If
End Sub

Public Sub ChangeItemCheckState(ByVal val As Boolean, ByVal item As ListViewItem)
    If Monitor.TryEnter(item, 10) Then
        Try
            item.Checked = val
        Finally
            Monitor.Exit(item)
        End Try
    End If
End Sub

Private Sub ListviewOPC_ItemCheck(sender As Object, e As ItemCheckEventArgs) Handles Me.ItemCheck
    If Monitor.IsEntered(Me.Items(e.Index)) Then
        'do nothing or other nessesary things.
    Else
        'prevent click from users
        If PreventUserCheckItem Then
            e.NewValue = e.CurrentValue
        End If
    End If
End Sub

NascarEd 17 年前

Grammarian 17 年前

你可以用 ObjectListView (它是普通.NET ListView的包装器)。它提供了一个回调CheckStatePutter,当用户单击复选框时调用该回调。在该回调中,您可以决定是否接受新的复选框值。

How do I use checkboxes in my ObjectListView?

JFV 17 年前

“项目检查” 而不是方法以下代码适用于我:

Private Sub clboxOptions_ItemCheck(ByVal sender As System.Object, ByVal e As System.Windows.Forms.ItemCheckEventArgs) Handles clboxOptions.ItemCheck
    Try
        If backupStarted = True Then
            If e.CurrentValue <> e.NewValue Then
                e.NewValue = e.CurrentValue
            Else
                e.NewValue = e.NewValue
            End If
        End If
End Sub

Cha Mildz 8 年前

我想禁用Listview中的复选框。当我点击按钮去。我使用的是“ItemChecked”方法。我使用以下代码:

Public Sub CheckBoxChecked(ByVal sender As Object, ByVal e As System.Windows.Forms.ItemCheckedEventArgs)
    Try
        If bCheckFromEvent Then
            bCheckFromEvent = False
            Return
        End If
        If BrunService Then
            bCheckFromEvent = True
            ListView.Items(e.Item.Index).Checked = Not ListView.Items(e.Item.Index).Checked
        End If

    Catch ex As Exception
            MsgBox("CheckBoxChecked: " & ex.Message, MsgBoxStyle.Critical Or MsgBoxStyle.OkOnly, "ERROR")
    End Try

End Sub