ComboBox NullReferenceException

[Former Member]

Hello

I'm newbie to SAP Business One Visual Studio programming.

In my project i need to fill ComboBox with Item Categories name and code.

The problem is when i try to pass value from Datasource to ComboBox.ValidValues I'm getting an NullReferenceException.

Here is my code:

private void Form_LoadAfter(SAPbouiCOM.SBOItemEventArg pVal)
        {
            Form oForm = null;
            oForm = SAPbouiCOM.Framework.Application.SBO_Application.Forms.Item(pVal.FormUID);
            oForm.DataSources.DataTables.Add("Item_data");
            SAPbouiCOM.DataTable dt = oForm.DataSources.DataTables.Item("Item_data");
            dt.ExecuteQuery("SELECT Code,Name FROM [@ITEMCATEGORY]");
            for (int i = 0; i < dt.Rows.Count; i++)
            {
                string oCode = dt.Columns.Item("Code").Cells.Item(i).Value.ToString();
                string oName = dt.Columns.Item("Name").Cells.Item(i).Value.ToString();
                try
                {
                    Debug.WriteLine("Code: "+oCode+" Name: "+oName);
                    ComboBox0.ValidValues.Add(oCode,oName);
                }
                catch(Exception ex)
                {
                }
            }
        }

Any kind of help will be appreciated.

Thank you

[ANKIT_CHAUHAN]

Hi hordeus,

Refer to the following discussion which mentions how to add Valid Values to a ComboBox:

https://answers.sap.com/questions/347691/how-to-bind-a-combobox-with-an-recorset-in-c.html

Hope it helps!

Kind regards,

ANKIT CHAUHAN

SAP Business One Support

[Former Member · Accepted solution]

Moved the loop which was adding values to ValidValues to OnInitializeComponent().

Now everything is working thanks for the info.

[edy_simon]

Make sure your ComboBox0 is not null.
Your code did not show where you initialize this

[Former Member]

public override void OnInitializeComponent()
        {
            this.StaticText0 = ((SAPbouiCOM.StaticText)(this.GetItem("Item_0").Specific));
            this.StaticText1 = ((SAPbouiCOM.StaticText)(this.GetItem("Item_1").Specific));
            this.StaticText2 = ((SAPbouiCOM.StaticText)(this.GetItem("Item_2").Specific));
            this.StaticText3 = ((SAPbouiCOM.StaticText)(this.GetItem("Item_5").Specific));
            this.StaticText4 = ((SAPbouiCOM.StaticText)(this.GetItem("Item_6").Specific));
            this.StaticText5 = ((SAPbouiCOM.StaticText)(this.GetItem("Item_7").Specific));
            this.EditText2 = ((SAPbouiCOM.EditText)(this.GetItem("Item_8").Specific));
            this.EditText3 = ((SAPbouiCOM.EditText)(this.GetItem("Item_9").Specific));
            this.Button0 = ((SAPbouiCOM.Button)(this.GetItem("Item_10").Specific));
            this.Button0.ClickAfter += new SAPbouiCOM._IButtonEvents_ClickAfterEventHandler(this.Button0_ClickAfter);
            this.Button1 = ((SAPbouiCOM.Button)(this.GetItem("Item_11").Specific));
            this.Button1.ClickAfter += new SAPbouiCOM._IButtonEvents_ClickAfterEventHandler(this.Button1_ClickAfter);
            this.ComboBox0 = ((SAPbouiCOM.ComboBox)(this.GetItem("Item_13").Specific));
            this.EditText4 = ((SAPbouiCOM.EditText)(this.GetItem("Item_15").Specific));
            this.OnCustomInitialize();
        }

Here is the initialization part. And yes ComboBox is null but i can't seem insert anything.

[former_member11696]

Try logging onto the data source before getting the collection.

I fill list boxes this way:

LstInterpolationMode.Enabled = true;

Array CRinterpolationMode = Enum.GetValues(typeof(System.Drawing.Drawing2D.InterpolationMode));

foreach (object obj in CRinterpolationMode)

{

LstInterpolationMode.Items.Add(obj);

}

LstInterpolationMode.SelectedItem = System.Drawing.Drawing2D.InterpolationMode.NearestNeighbor;