Contextual Menu Implementation

General
1

I have listbox with multiple columns. I have a column for “Order Status”, “Order Type”, “Requested Ship Date”. When the user right clicks on the cell for each of these I want to build a contextual menu to allow the user to select from a list of values, based on the column and cell clicked. I want the contextual menu to be dynamic and related to the type of cell clicked (date, status, etc.), or “contextual”.

I noticed that the event ConstructContextualMenu does not pass the row and column which I could used to add the appropriate menu items (seems odd). I could define a property and store those on the CellClick event to use when contextual click occurs, but that seems a little messy. I could just define my own menu on the cell click event and do that instead of using ConstructContextualMenu.

This is on Windows 10.

Suggestions for best implementation or ideas?

2

something like this?


Function CellPressed(row As Integer, column As Integer, x As Integer, y As Integer) Handles CellPressed as Boolean
  If IsContextualClick Then
    Var m As New DesktopMenuItem
    m.AddMenu New DesktopMenuItem("Abc","Tag")
    Var item As DesktopMenuItem = m.PopUp
    If item<> Nil Then
      System.DebugLog item.Tag
      System.DebugLog Me.CellTextAt(row, column)
    End If
    Return True
  End If
End Function
1 Like
3

In h ConstructContextualMenu event you can use the X and Y value passed in to get the row and column using (API 1) Listbox.RowFromXY and Listbox.ColumnFrom XY…

That said it would have made sense fro Xojo to pass them in for a listbox … but I suspect they wanted to keep the even the same for all RectControls.

-Karen

2 Likes
4

Or they could implement a CellConstructContextualMenu(row, column) as Boolean and if not handled, raise the ConstructContextualMenu event. And they could then position the contextual menu adjacent to the cell, etc., etc. Which is basically what I did in my own code. There’s a menu for the cell, and if not handled, a menu for the listbox as a whole.

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5

I don’t see any problem in the ConstructContextualMenu you can write:

Var row As Integer=Me.RowFromXY(x, y)
Var column As Integer=Me.ColumnFromXY(x, y)
base.AddMenu New DesktopMenuItem(row.ToString+"; "+column.ToString)

they use the same x, y parameters for two reasons:consistency and you can need the x and/or y and row and column can be obtained easily.
BTW row is also me.selectedRowIndex

1 Like
6

All great suggestions. Thanks for everyone’s help.

7

Why do RowFromXY and ColumnFromXY take both x and y, by the way? A column doesn’t need the y parameter to be discovered and a row doesn’t need x either.
Always wondered… :thinking:

8

Because the underlying APIs calculate both at the same time.

9

Thanks.
This shifts the question to “why does the API calculate both?”. In the end, calculating a row won’t even involve the x axis and calculating a column never has to deal with the y axis.
Sounds silly to me… :man_shrugging:

10

Think about clicking on the header or a scroll bar . They are internal to the list box abd a header is not a row and a click on a scroll bar is not a click on a row or column.

You need both coordinates to get a correct result.

11

Because the underlying call is “get me the cell for this x and y”. Being able to get the column or row still requires both and it cannot be inferred.

12

Then a unique result as Pair could be a good solution to avoid the double call (if some one need both the values)

13

called Vector2D :slight_smile: (or Point)