I know I have to be doing something wrong but just can't find the issue. I am using v3.9 of the .Net Grid.

Problem: When the grid is displayed in the form, the combobox column is displaying the value of the column from the binding dataset for the grid. When I click on the cell, the combox displays the appropriate caption information. But when I move off the cell, the value either becomes empty or returns to the original value of the row from the binding dataset.

The dataset contains multiple datatables without any relations established. The grid is bound to one of the datatables and the combobox is bound to a different datatable.

The key value for the combo box is a string value (Alpha-Numeric). Not a typical numeric Id value showing a string Caption.

What is going wrong?

Here is my code:

         'Set the Grid Properties

        grdExportDetails.Enabled = True

        grdExportDetails.BeginInit()

        'Datasource

        grdExportDetails.SetDataBinding(dsExportDetails, "ProgramBase")

        'Headers

        grdExportDetails.HeaderRows.Add(columnManagerRow)

        grdExportDetails.Columns("ProgramId").Visible = False

        grdExportDetails.Columns("PackageId").Visible = False

        'Editing with single click

        grdExportDetails.SingleClickEdit = True

        'Checkbox column

        grdExportDetails.Columns("Selected").VisibleIndex = 0

        grdExportDetails.Columns("Selected").Width = 50

        grdExportDetails.Columns("Selected").CellEditorManager = New CheckBoxEditor()

        grdExportDetails.Columns("Selected").CellViewerManager = New CheckBoxViewer()

        grdExportDetails.Columns("Selected").HorizontalAlignment = HorizontalAlignment.Center

        grdExportDetails.Columns("Selected").VerticalAlignment = VerticalAlignment.Center

        'Dropdown columns

        'Currency

        CurrencyComboBoxEditor = New ComboBoxEditor(dsExportDetails, "ExchangeRates", "ExchangeSetName", "%RateDescriptor%")

        CurrencyComboBoxEditor.TemplateControl.AllowDropDown = True

        CurrencyComboBoxEditor.TemplateControl.AllowFreeText = False

        grdExportDetails.Columns("ProgBaseCurrency").CellEditorManager = CurrencyComboBoxEditor

        grdExportDetails.Columns("ProgBaseCurrency").HorizontalAlignment = HorizontalAlignment.Left

        'Readonly the other columns

        grdExportDetails.Columns("ProgBaseWeight").ReadOnly = True

        grdExportDetails.Columns("ProgBaseDistance").ReadOnly = True

        grdExportDetails.Columns("ProgBaseEnergy").ReadOnly = True

        grdExportDetails.Columns("Idnum").ReadOnly = True

        grdExportDetails.EndInit()

Hi Emerson,

You will need to set the binding for the CellViewerManager. As I can see from your code, you are not doing this. Try doing the following:

Visual Basic
-------------------

grdExportDetails.Columns("Selected").CellViewerManager = New CheckBoxViewer(dsExportDetails, "ExchangeRates", "ExchangeSetName", "%RateDescriptor%")
-------------------

This should solve the issue as to why you cannot see the value stay at the one that is chosen.

Thanks for the reply but the problem is with the Combobox and not the checkbox. The checkbox works just fine.

As for setting the CellViewerManager for the Combobox, I try to do that and I get an error indicating that the Key value - blah blah has already been loaded into some dictionary.

Additionally, the initial displayed value in the column with the combobox is the value member and not the display member.

Hi Emerson,

Are you able to send me a small self-contained sample application so that way I can investigate the issue? With this information, I will be able to provide you with an answer.

Hi Emerson,

is it possible to recreate the issue with dummy data? 

I'm not sure how to create a sample app that has self contained data not coming from a database. Seems kind of funny to me that in all my years of programming I have never needed to anything like that.

I guess thinking about it, I would just need to code the building of the dataset and tables manually. Any suggestions on other easier, quicker ways would be appreciated. 

Hi Emerson,

I have attached a small sample to get you started... Let me know if you can reproduce it. I will continue to investigate the issue.

Marc,

How do I upload a zip file when I have it ready?

I do not see any option within my browser when replying to the post to do so.

Thanks. 

Hi Emerson,

When you reply to this forum post, there is an 'Options' tab right about the text box. Click on it and you should see that you can add an attachment.

Marc,

Attached is sample project replicating the error that I get using the CellViewManager, not being able to see the RateDescriptor value in the column instead of the Id value of CURRDOL and the ComboxBox selection not being saved when changed.

Thanks.

Hi Emerson,

I believe the code is fine. I had just noticed that with the data you had, I couldn't tell which one was which because I was only seeing the ID (which were all the same in the dummy data). I have re-attached the sample and as you can see it works. 

Marc,

The data sample I sent to you was exactly what is going to be received for consumption by the grid. Changing the sample data does not resolve the issue.

To give you a bit more of an idea of what needs to be done, I have attached an Excel worksheet with a sample of the actual  ExchangeRates structure with the data anonymized.

The key value for each facility linking to the ExchangeRates structure is the ExchangeSetName. Just happens to be a String and not an integer value. Each ExchangeSetName has N number of RateDescriptors describing the value contained in the Rate column.

The user is being shown the RateDescriptor values in the combo box that are available for each facilities ExchangeSetName. After the selection of the desired RateDescriptor by the user, a currency conversion process will take place using the Rate value for the selected RateDescriptor within the facilities ExchangeSetName.

I hope this helps because we can not change the data to make the ComboBox work in the grid.

Marc,

 Now that I have had the weekend to review everything again, I believe there may be room for manipulation of the data columns into a more standard lookup style format utilizing the Id column within the data.

Let me try a few things and will post back the results later today or tomorrow.