Programmatically change row color in procedure or function in UI for WinForms

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Programmatically change row color in procedure or function

9 Answers 233 Views

GridView

This is a migrated thread and some comments may be shown as answers.

Kevin Weir asked on 31 Mar 2011, 01:03 AM

I currently have a save button click event that calls a procedure named ValidateData. The ValidateData procedure iterates through rows in the grid and sets the color or the row to red if the data therin is invalid. The problem I have is that after upgrading to RadControls 2011 Q1 the VisualElement property is no longer available. I have been searching through these forums for a couple of hours and haven't run across a viable way of dealing with this. Is there an easy way to accomplish this? I don't believe the RowFormatting Event applies in my case.

Much appreciated
Kevin

Private Function ValidateData() As Boolean

Dim entBundleComponent As BundleComponent

Dim isValid As Boolean = True

Dim isValidRow As Boolean = True

Dim gvRow As UI.GridViewRowInfo

For Each gvRow In gvComponents.Rows

isValidRow =

True

entBundleComponent =

CType(gvRow.DataBoundItem, BundleComponent)

If entBundleComponent.COMPONENT_NAME.Trim().Length = 0 Then

isValid =

False

isValidRow =

False

End If

If entBundleComponent.COMPONENT_DESCRIPTION.Trim().Length = 0 Then

isValid =

False

isValidRow =

False

End If

If isValidRow Then

gvRow.VisualElement.BackColor = Color.Transparent

gvRow.VisualElement.DrawFill =

True

Else

gvRow.VisualElement.BackColor = Color.Red

gvRow.VisualElement.DrawFill =

True

End If

If isValid Then

txtMessages.Text =

"Ok"

txtMessages.ForeColor = Color.Black

Else

txtMessages.ForeColor = Color.Red

txtMessages.Text =

"Please correct errors before saving."

End If

Return isValid

End Function

9 Answers, 1 is accepted

Accepted

answered on 31 Mar 2011, 08:29 AM

Hello Kevin,

You should use RowFormatting for this one, something like this:

Private Sub RadGridView1_RowFormatting(ByVal sender As Object, ByVal e As Telerik.WinControls.UI.RowFormattingEventArgs) Handles RadGridView1.RowFormatting

'check for null databound item

entBundleComponent = CType(gvRow.DataBoundItem, BundleComponent)

If entBundleComponent.COMPONENT_NAME.Trim().Length = 0 Then

e.RowElement.DrawFill = True

e.RowElement.GradientStyle = GradientStyles.Solid

e.RowElement.BackColor = Color.Red

Else

e.RowElement.ResetValue(LightVisualElement.BackColorProperty, ValueResetFlags.Local)

e.RowElement.ResetValue(LightVisualElement.GradientStyleProperty, ValueResetFlags.Local)

e.RowElement.ResetValue(LightVisualElement.DrawFillProperty, ValueResetFlags.Local)

End If

End Sub

For more info please take a look at the following help article.

Hope this helps, if you have any other questions or comments, please let me know,

Best Regards,
Emanuel Varga

Telerik WinForms MVP

answered on 06 Oct 2014, 02:21 PM

Hello Jonald,

Thank you for writing.

Due to the UI virtualization in RadGridView, cell/row elements are created only for currently visible cells/rows and are being reused during operations like scrolling, filtering, grouping and so on.
In order to prevent applying the formatting to other columns' cell/row elements (because of the cell reuse) all customization should be reset for the rest of the cell/row elements. It is recommended to reset not only the DrawFill property, but the all the properties you set, including BackColor and the GradientStyle properties. You can refer to our Formatting Cells and Formatting Rows help articles which are quite useful about this topic.

I am not sure why you are iterating through all the items in the list box for a specific row in the RowFormatting event, but if a certain list box item is equal to the cell's value and you apply a specific style to the cell, the next item would not be the same and you will reset the applied settings. You should either use break to stop the iteration when a match is found or use another approach for using the list box data inside the RowFormatting event handler. You can find below a sample code snippet demonstrating how to change the row's back color for the currently selected item in the list box:

public Form1()

{

InitializeComponent();

List<Item> items = new List<Item>();

for (int i = 0; i < 30; i++)

{

items.Add(new Item(i,"Item" + i));

}

this.radGridView1.DataSource = items;

this.radGridView1.AutoSizeColumnsMode = GridViewAutoSizeColumnsMode.Fill;

this.listBox1.DataSource = items;

this.listBox1.DisplayMember = "Title";

this.listBox1.ValueMember = "Id";

}

public class Item

{

public int Id { get; set; }

public string Title { get; set; }

public Item(int id, string title)

{

this.Id = id;

this.Title = title;

}

private void radGridView1_RowFormatting(object sender, Telerik.WinControls.UI.RowFormattingEventArgs e)

{

if ((int)e.RowElement.RowInfo.Cells[0].Value == ((Item)listBox1.SelectedItem).Id)

{

e.RowElement.DrawFill = true;

e.RowElement.GradientStyle = Telerik.WinControls.GradientStyles.Solid;

e.RowElement.BackColor = Color.Red;

}

else

{

e.RowElement.ResetValue(LightVisualElement.BackColorProperty, ValueResetFlags.Local);

e.RowElement.ResetValue(LightVisualElement.GradientStyleProperty, ValueResetFlags.Local);

e.RowElement.ResetValue(LightVisualElement.DrawFillProperty, ValueResetFlags.Local);

}

I hope this information helps. Should you have further questions, I would be glad to help.

Regards,
Desislava
Telerik

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