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The menu editor in VB is great for creating simple menu structures, but
menus displaying options employing checked entries require some additional
coding behind the menu objects. If you're familiar with the menu editor,
then creating menus such as the File menu with Open, Save, Print and Exit
entries etc. is straight forward. The event handling behind these menus is
also simple, as follows:
Private Sub mnuOpen_Click()
'code to open and retrieve appropriate files...
End Sub
Similarly the menus for Save and Exit are handled separately with the
mnuSave and mnuExit click events.
However, option menus such as the one below require some additional
coding to reflect the option status as follows:
Private Sub mnuShowOK_Click()
If mnuShowOK.Checked then 'don't show OK bttn
mnuShow.Checked = False
cmdOK.Visible = False
Else
mnuShow.Checked = True 'show OK bttn
cmdOK.Visible = True
End If
End Sub
Menu options containing multiple entries (as shown below), that are
mutually exclusive are handled with menu control arrays as follows:
Private Sub mnuDragDrop_Click(Index As Integer)
'Index 0 - Enable Drag and Drop
'Index 1 - Disable Drag and Drop
If mnuDragDrop(0).Checked and Index = 1 then
mnuDragDrop(1).Checked = True
'code disabling functionality
ElseIf mnuDragDrop(1).Checked and Index = 0 then
mnuDragDrop(0).Checked = True
'code enabling functionality
End If
End Sub
The If...ElseIf statement may look a little confusing, but basically,
If mnuDragDrop(0).Checked and Index = 1 then
determines if 'Enable Drag and Drop' is checked and also if 'Disable Drag
and Drop' is selected and if both these conditions are met then 'Disable
Drag and Drop' is checked instead. Obviously, the opposite is applicable
for the ElseIf statement. No other conditions are required such as,
If mnuDragDrop(0).Checked and Index = 0 then
this would be pointless, because if 'Enable Drag and Drop' is checked and
'Enable Drag
and Drop' is selected then nothing needs to happen as 'Enable Drag
and Drop' is already the chosen option. Options groups with more than two
choices can be handled this way, but if more than one option group exists
under the same menu heading then separator bars should be used for clarity
as follows:
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