Questions on UI for WinForms Forum

1 answer

6 views

Hello,
Currently using L4G (Version 11.7) in client mode (WebClient V11 on the PC)-server with a Pasoe configuration on the Linux server (where OpenEdge (DLC), PasOE, databases, and the _DB-REQUIRED program tree are located).
I need to migrate to version 12.2 + Telerik screen.
Do you have an example of a simple grid screen with CRUD management on a Be in client-server mode?
- Read the table: READ
- Create a record: CREATE
- Modify the table: UPDATE
- Delete a record: DELETE
Thank you

GridView

answered on 28 Jan 2026

2 answers

16 views

RADGRIDVIEW Performance Issue ?

i have a Master-Detail CRUD Job

Details shown using RADGRIDVIEW

for example : Master is "TBSYUSER" class Detail is "TBSYUSAU" class

change master will change detail data

i using BindingList<TBSYUSAU> --> BindingSource -> RADGRIDVIEW

now if detail data's count varing a little large

ex: record count change from 1 to 89 due to master change

RADGRIDVIEW refresh will take more times

should i change strucuture to : Datatable --> BindingSource -> RADGRIDVIEW

or have some suggestion ?

TKs

GridView

answered on 22 Jan 2026

1 answer

9 views

How to programmatically expand a GridViewComboBoxColumn

I would like to expand a GridViewComboBoxColumn list on the same row where on another column that is set to "Lost".

(see attached screenshot)
(1) User clicks on a cell and selects "Lost" from a list

(2) From Cell Event, the "Reason" column (GridViewComboBoxColumn) is automatically expanded so the user knows to select a reason.

		private void dgvSales_CellValidating(object sender, CellValidatingEventArgs e)
		{
			if(e.ColumnIndex >= 0 && e.RowIndex >= 0)
			{

				switch (e.ColumnIndex)
				{
					case int _ when e.ColumnIndex == dgvSales.Columns["colWonLost"].Index:
						if(e.Value.ToString() == "Lost")
						{
							dgvSales.CurrentRow.Cells["colReason"].IsSelected = true;
							
							//Add code here to expand colReason list


							return;
						}
						break;
					default:
						break;
				}
			}

		}  //dgvSales CellValidating

GridView

answered on 22 Jan 2026

4 answers

59 views

Datagridview - Column chooser

Hello,

I want to choose column by checkboxes, something like that:

I

It is possible?

Thank you for your answer

CheckedListBox

GridView

answered on 22 Jan 2026

1 answer

11 views

How to disable some default Column Header Context Menu ?

i want to disable some default Column Header Context Menu like "Sort Ascdnging" "Sort Descending" ...

How to do ?

Also i want to disable some default Cell Column Context Menu ? TKS

GridView

answered on 20 Jan 2026

1 answer

17 views

Make a row of RADGRIDVIEW as "Deleted"

i use RADGRIDVIEW to show datas

i want to let use to select some rows as "Deleted"

to delete these datas form DataBase

how can i let these rows shown as the following

the example is done by using C# default DataGridView

How can be done in RADGRIDIEW ?

GridView

answered on 20 Jan 2026

1 answer

26 views

GridView cell formatting in custom columns

Hello,

I would like to ask two questions about custom columns in GridView. I'm putting them into one thread since they're related.

1. What's the relationship between SetContentCore and OnCellFormatting? Is it ok to set formatting in SetContentCore? This is how it seems to me to be correct:

		protected override void SetContentCore(object value)
		{
			if (value is Quality q)
			{
				if (q == Quality.None)
					Text = "--";
				else
					Text = q.ToString();
			}
			else
				base.SetContentCore(value);
		}

		protected override void OnCellFormatting(CellFormattingEventArgs e)
		{
			ResetValue(VisualElement.BackColorProperty, ValueResetFlags.Local);
			ResetValue(VisualElement.ForeColorProperty, ValueResetFlags.Local);
			ResetValue(LightVisualElement.NumberOfColorsProperty, ValueResetFlags.Local);
			ResetValue(LightVisualElement.DrawFillProperty, ValueResetFlags.Local);

			if (Value is Quality q)
			{
				switch (q)
				{
					case Quality.OK:
						BackColor = Color.Lime;
						NumberOfColors = 1;
						DrawFill = true;
						break;
					case Quality.NOK:
						BackColor = Color.Red;
						NumberOfColors = 1;
						DrawFill = true;
						break;
					case Quality.Error:
						BackColor = Color.DodgerBlue;
						NumberOfColors = 1;
						DrawFill = true;
						break;
				}
			}

			base.OnCellFormatting(e);
		}

But this also works. I tried it mainly because of the second question, and Copilot actually suggested it as the first styling approach.

		protected override void SetContentCore(object value)
		{
			if (value is Quality q)
			{
				if (q == Quality.None)
					Text = "--";
				else
					Text = q.ToString();

				ResetValue(VisualElement.BackColorProperty, ValueResetFlags.Local);
				ResetValue(VisualElement.ForeColorProperty, ValueResetFlags.Local);
				ResetValue(LightVisualElement.NumberOfColorsProperty, ValueResetFlags.Local);
				ResetValue(LightVisualElement.DrawFillProperty, ValueResetFlags.Local);

				switch (q)
				{
					case Quality.OK:
						BackColor = Color.Lime;
						NumberOfColors = 1;
						DrawFill = true;
						break;
					case Quality.NOK:
						BackColor = Color.Red;
						NumberOfColors = 1;
						DrawFill = true;
						break;
					case Quality.Error:
						BackColor = Color.DodgerBlue;
						NumberOfColors = 1;
						DrawFill = true;
						break;
				}
			}
			else
				base.SetContentCore(value);
		}

2. Is there any way to override how Value is retrieved from the DataBoundItem? In one of my column types, I can't use FieldName directly. In classic DataGridView, I could override GetValue / SetValue like this:

		protected override object GetValue(int rowIndex)
		{
			DgvRealResultColumn col = OwningColumn as DgvRealResultColumn;
			object obj = DataGridView.Rows[rowIndex].DataBoundItem;
			if ((col == null) || (obj == null))
				return base.GetValue(rowIndex);

			object resultValue = GetResultValue(rowIndex, col, obj);
			Quality q = (Quality)Convert.ToInt32(resultValue);
			if (!QualityHelper.HasValue(q))
				return null;

			if (obj is RealResult rr)
				return rr.Value;

			string propName = string.Format("R{0:D3}Value", col.ItemIndex);
			PropertyInfo pi = obj.GetType().GetProperty(propName);
			return pi.GetValue(obj, null);
		}

I don't see anything like that in Telerik GridView. So far, I came up with this workaround:

		protected override void SetContentCore(object value)
		{
			TestResult r = null;
			var obj = RowInfo.DataBoundItem;
			if (obj is TestResult)
				r = (TestResult)obj;
			else if (obj is TestItem item)
			{
				var col = ColumnInfo as RgvTestResultColumn;
				if ((col != null) && (item.Results != null) && (col.ResultIndex < item.Results.Length))
					r = item.Results[col.ResultIndex];
			}

			ResetValue(VisualElement.BackColorProperty, ValueResetFlags.Local);
			ResetValue(VisualElement.ForeColorProperty, ValueResetFlags.Local);
			ResetValue(LightVisualElement.NumberOfColorsProperty, ValueResetFlags.Local);
			ResetValue(LightVisualElement.DrawFillProperty, ValueResetFlags.Local);

			if (r == null)
			{
				base.SetContentCore(value);
				return;
			}

			switch (r.Result)
			{
				case Quality.OK:
					Text = r.Value.ToString("F1");
					BackColor = Color.Lime;
					NumberOfColors = 1;
					DrawFill = true;
					break;
				case Quality.NOK:
					Text = r.Value.ToString("F1");
					BackColor = Color.Red;
					NumberOfColors = 1;
					DrawFill = true;
					break;
				case Quality.Error:
					Text = "X";
					BackColor = Color.DodgerBlue;
					NumberOfColors = 1;
					DrawFill = true;
					break;
				default:
					Text = "--";
					break;
			}
		}

But in this case, it doesn't set the internal Value, so when I write rgv.Rows[0].Cells["colR0"].Value in code, I always get null. Is there any way to solve this? I am attaching my test code for testing.

GridView

answered on 01 Jan 2026

2 answers

72 views

RadMenuItem's TEXT shown too small ? how can i fix it ?

GridView

answered on 26 Dec 2025

2 answers

38 views

RadPageView DragDrop - copy Row from RadPageView to System.Windows.Forms.DataGridView

Hello,

I’m working with some older forms that use System.Windows.Forms.DataGridView. The form is quite complex, so converting it to Telerik isn’t straightforward.

I’d like to copy a row from RadPageView. Could you please provide a sample code snippet showing how to achieve this?

Thank you!

Radek

GridView

answered on 17 Dec 2025

1 answer

57 views

Behavior of the Text property in GridView CellFormatting event

Hello,

I have a question about the behavior of the Text property in the CellFormatting event in GridView. I understand that GridView uses UI virtualization, and that I need to reset all modified properties for the rest of cells. But how does the Text property behave? I looked through the forum and found this example:

private void radGridView1_CellFormatting(object sender, CellFormattingEventArgs e)
        {
            if (e.Column.Name == "Description")
            {
                e.CellElement.Text = e.CellElement.Value + " END";
                e.CellElement.Image = Properties.Resources.OutlookViewCalendar;
                e.CellElement.DrawImage = true;
                e.CellElement.TextImageRelation = TextImageRelation.TextBeforeImage;
            }
            else
            { 
                e.CellElement.ResetValue(LightVisualElement.ImageProperty, ValueResetFlags.Local);
                e.CellElement.ResetValue(LightVisualElement.DrawImageProperty, ValueResetFlags.Local);
                e.CellElement.ResetValue(LightVisualElement.TextImageRelationProperty, ValueResetFlags.Local);
            }
        }

In this example, all properties are reset except Text. When I tried to reset Text, all cell texts disappeared, except the ones I set manually in CellFormatting. So I think Text has special behavior in CellFormatting, and it's always set from Value at the beginning and it's not affected by UI virtualization and reusing cells. Is that correct?

Also, just to be sure, in all examples I saw the if/else pattern. But functionally, is it the same as if I reset all properties I want to change at the beginning, and then set them later? Or can this have some performance impact? The reason I ask is that I use a switch with more branches, and it would be hard to track what needs to be reset in each one.

Here is my case. And I was also thinking, in my case, is it correct to reset the properties before checking ColumnIndex and RowIndex, or after?

private void rgv_CellFormatting(object sender, CellFormattingEventArgs e)
		{
			e.CellElement.ResetValue(LightVisualElement.BackColorProperty, ValueResetFlags.Local);
			e.CellElement.ResetValue(LightVisualElement.NumberOfColorsProperty, ValueResetFlags.Local);
			e.CellElement.ResetValue(LightVisualElement.DrawFillProperty, ValueResetFlags.Local);
			e.CellElement.ResetValue(LightVisualElement.PaddingProperty, ValueResetFlags.Local);
			//e.CellElement.ResetValue(LightVisualElement.TextProperty, ValueResetFlags.Local);

			if ((e.ColumnIndex < 0) || (e.RowIndex < 0))
				return;

			var ed = e.Row.DataBoundItem as TestParEditorItem;
			if (ed == null)
				return;

			bool isSub = ed.IsSubItem;
			bool hasSub = ed.HasSubItems;

			switch (e.Column.Name)
			{
				case "colR":
				case "colFi":
				case "colR2":
				case "colFi2":
					if (isSub)
						e.CellElement.Text = "";
					break;

				case "colMin":
				case "colMax":
					if (hasSub)
						e.CellElement.Text = "";
					break;

				case "colAct":
					e.CellElement.BackColor = SystemColors.ControlLight;
					e.CellElement.NumberOfColors = 1;
					e.CellElement.DrawFill = true;
					break;

				case "colType":
					if (isSub)
					{
						e.CellElement.Text = ed.SubItemName;
						e.CellElement.Padding = new Padding(30, 0, 0, 0);
					}
					else
					{
						e.CellElement.Padding = new Padding(0, 0, 0, 0);
					}
					break;
			}
		}

Thanks.

GridView

answered on 16 Dec 2025