Creating ArcMap context menu's

Question

actually i am in need of some requirment regarding context menus.

We created our own button in the context menu which will call a exe file whenever that option in selected in the context menu.

The problem is that this button is that it only should be enabled when a particular area on our map is selected. Otherwise it should be disabled.

As i am new to this arcGIS ..need help on this.

Answer 1

I'm not sure if you are programming in ArcMap VBA or Visual Studio?

In VBA you could create a UITool on mouse down event which searches for, I'm assuming a certain layer or project area layer that is selected or not. You could assign the selction count to a function then define your button's enable or disable state according if the function returns 0 or >0.

In Visual Studio same concept applies, however you will use a BaseTool instead of a UITool.

Below is an ArcObjects code sample of how to do a feature selection with a UITool in VBA.

Private Sub UIToolControl1_MouseDown(ByVal button As Long, ByVal shift As Long, ByVal x As Long, ByVal y As Long)

    Call layerselection

End Sub

Private Function layerselection() As Integer

'arcmap command for featue selection tool

Dim pUID As New UID
  Dim pCmdItem As ICommandItem
  ' Use the GUID of the Save command
  pUID.value = "{78FFF793-98B4-11D1-873B-0000F8751720}"
  pUID.SubType = 3
  Set pCmdItem = Application.Document.CommandBars.Find(pUID)
  pCmdItem.Execute

    ' Part 1: Set the variables.
    Dim pMxDoc As IMxDocument
    Dim pMap As IMap
    Dim pActiveView As IActiveView
    Dim pFeatureLayer As IFeatureLayer
    Dim pLayer As ILayer
    Dim pEnumLayer As IEnumLayer
    Set pMxDoc = ThisDocument

    Set pMap = pMxDoc.ActiveView.FocusMap
    Set pActiveView = pMap
    Set pEnumLayer = pMap.Layers

    Set pLayer = pEnumLayer.Next
    Do Until pLayer Is Nothing
        If pLayer.Name = "MyLayer" Then
            Set pFeatureLayer = pLayer

        ElseIf pLayer.Name <> "MyLayer" Then
        layerselection = 0

          Exit Function

        End If
        Set pLayer = pEnumLayer.Next
    Loop

    ' Part 2: Select features.
    Dim pQueryFilter As IQueryFilter
    Dim pFeatureSelection As IFeatureSelection

    Set pFeatureSelection = pFeatureLayer
    pFeatureSelection.SelectFeatures pQueryFilter, esriSelectionResultNew, False
    ' Refresh again to draw the new selection.
    pActiveView.PartialRefresh esriViewGeoSelection, Nothing, Nothing

    layerselection = pFeatureSelection.SelectionSet.count

End Function

Answer 2

Well, whenever the context menu popups you should check for your condition, and if false, disable the button.

There are many ways to do this. You can create separate menus and then decide which you need to show or you can create the menu dinamically, depending on your conditions.

Theres is a good ESRI how to here:http://resources.esri.com/help/9.3/ArcGISDesktop/dotnet/fa426537-6141-4c1b-8562-df5e18daabbc.htm

Hope it helps