Telerik，处理单击RadDropDownButton文本区域

Question

我有一个带有预定义文本和一个RadDropDownButton的RadMenuItem

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当我单击文本区域(而不是箭头)时，我的意图是执行一个操作：

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然后在单击可选择项时执行其他操作：

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处理RadMenuItem.Click已经完成，没有问题，但是当我单击控件上的任何地方而不仅仅是文本区域时，RadDropDownButton.Click事件就会触发。

我怎样才能解决这个问题，让控件按我的意愿工作呢？

Private sub MyRadDropDownButton_click() handles MyRadDropDownButton.click

    ' this instruction should be launched only when clicking on the "Analyze" word.
    ' this means everywhere on the control but not on the arrow.
    msgbox("you've clicked on the "Analyze" word")

end sub

Answer 1

他们的SplitButton有点聪明，国际海事组织。大多数SplitButton将箭头区域视为虚拟按钮，或者跳过发出按钮CLick事件，或者显示相关的下拉菜单(或者两者兼而有之)。当单击该区域时，大多数用户使用一个新的SplitClicked事件，这样您就可以根据需要修改菜单：

Protected Overrides Sub OnMouseDown(ByVal mevent As MouseEventArgs)
    ...

    ' they clicked in the arrow.split rect
    If (SplitRect.Contains(mevent.Location)) Then

        ' notify them 
        RaiseEvent SplitClick(Me, New EventArgs)

        ' open the menu if there is one
        If ShowContextMenuStrip() = False Then
            skipNextClick = True       ' fixup for the menu
        End If         

    Else
        ' let the normal event get raised
        State = PushButtonState.Pressed
        MyBase.OnMouseDown(mevent)
    End If

End Sub 

它们没有类似的事件，但作为解决办法，您可以使用DropDownOpening事件“取消”按钮单击事件(这是因为DropDownOpening事件总是首先触发)：

' workaround flag
Private IgnoreClickBecauseMenuIsOpening As Boolean
Private Sub RadSplitButton1_DropDownOpening(sender As Object, 
          e As EventArgs) Handles RadSplitButton1.DropDownOpening

    IgnoreClickBecauseMenuIsOpening = True
    ' code to modify menu (or not)

End Sub

Private Sub RadSplitButton1_Click(sender As Object, 
        e As EventArgs) Handles RadSplitButton1.Click

    ' ignore click if menu is opening
    If IgnoreClickBecauseMenuIsOpening Then
        ' reset flag
        IgnoreClickBecauseMenuIsOpening = False
        Exit Sub                    ' all done here
    End If
    ' normal code to execute for a click
End Sub

Answer 2

解决办法：

我称之为“区分箭头单击而没有默认项集”，这对RadDropDownButton和RadSplitButton都适用。

Public Class RadSplitButton_TestForm

''' <summary>
''' Flag that determines whether the RadSplitButton menu-opening should be canceled.
''' </summary>
Private CancelOpening As Boolean = False

Private Sub RadSplitButton1_DropDownOpening(ByVal sender As Object, ByVal e As System.ComponentModel.CancelEventArgs) _
Handles RadSplitButton1.DropDownOpening

    e.Cancel = Me.CancelOpening

End Sub

Private Sub RadSplitButton1_MouseMove(ByVal sender As Object, ByVal e As MouseEventArgs) _
Handles RadSplitButton1.MouseMove

    Me.CancelOpening = Not sender.DropDownButtonElement.ArrowButton.IsMouseOverElement

End Sub

Private Sub RadSplitButton1_MouseDown(ByVal sender As Object, ByVal e As MouseEventArgs) _
Handles RadSplitButton1.Click

    If e.Button = Windows.Forms.MouseButtons.Left AndAlso Me.CancelOpening Then
        MsgBox("clicked out the arrow!")

    ElseIf Not Me.CancelOpening Then
        MsgBox("clicked over the arrow!")

    End If

End Sub

End Class

PS:首先，我试图确定mouseposition是否超过了ArrowButton.ClientRectangle，但它并没有给出预期的结果。