Questions on UI for WinForms Forum

27 answers

506 views

Hi!

I have to use custom cell to display data but I have problem with performance.

I have 500 rows and when I use my custom cell scrolling is very slow, not fluent.

I made simple test and checked that even if I add only one child control to custom cell, scrolling performance goes down significantly.

Is there any way to improve performance in this kind of scenario?

This is my source code:

public class CustomCell : GridDataCellElement

{

private RadCheckBoxElement _chk;

public CustomCell(GridViewColumn column, GridRowElement row) : base(column, row)

{

}

protected override void CreateChildElements()

{

base.CreateChildElements();

_chk = new RadCheckBoxElement();

_chk.Margin = new Padding(2, 2, 2, 2);

_chk.MinSize = new Size(20, 20);

_chk.Text = string.Empty;

_chk.ToggleState = ToggleState.Off;

this.Children.Add(_chk);

}

protected override Type ThemeEffectiveType

{ get { return typeof(GridDataCellElement); } }

}

namespace PerformanceIssue

{

public partial class Form1 : Form

{

List<MySample> _list;

public Form1()

{

InitializeComponent();

_list = this.GenerateList();

}

private void btnPopulateUnbound_Click(object sender, EventArgs e)

{

GridViewDataColumn col = null;

GridViewRowInfo row = null;

for (int index = 1; index <= 10; index++)

{

col = new CustomColumn();

radGridViewUnbound.Columns.Add(col);

col.Width = 100;

}

foreach (MySample item in _list)

{

row = radGridViewUnbound.Rows.AddNew();

row.Cells[0].Value = item.Property1;

row.Cells[1].Value = item.Property2;

row.Cells[2].Value = item.Property3;

row.Cells[3].Value = item.Property4;

row.Cells[4].Value = item.Property5;

row.Cells[5].Value = item.Property6;

row.Cells[6].Value = item.Property7;

row.Cells[7].Value = item.Property8;

row.Cells[8].Value = item.Property9;

row.Cells[9].Value = item.Property10;

}

radGridViewUnbound.MultiSelect = true;

}

private List<MySample> GenerateList()

{

List<MySample> list = new List<MySample>();

MySample item = null;

for (int index = 0; index < 500; index++)

{

item = new MySample()

{

Property1 = string.Format("Row: {0}, Col: {1}", index, 1),

Property2 = string.Format("Row: {0}, Col: {1}", index, 2),

Property3 = string.Format("Row: {0}, Col: {1}", index, 3),

Property4 = string.Format("Row: {0}, Col: {1}", index, 4),

Property5 = string.Format("Row: {0}, Col: {1}", index, 5),

Property6 = string.Format("Row: {0}, Col: {1}", index, 6),

Property7 = string.Format("Row: {0}, Col: {1}", index, 7),

Property8 = string.Format("Row: {0}, Col: {1}", index, 8),

Property9 = string.Format("Row: {0}, Col: {1}", index, 9),

Property10 = string.Format("Row: {0}, Col: {1}", index, 10)

};

list.Add(item);

}

return list;

}

Regards

GridView

answered on 18 Nov 2010

15 answers

305 views

Focus a filter box by program

I use RadGridView ver 8.2.0.0 (2008 Q3) with VB.NET 2010 and i need set the focus in a filter box for a column. How i make this?

Sorry for my english, i'm spanish

GridView

answered on 18 Nov 2010

3 answers

266 views

Change colors in disabled mode

Hi,

I have a WinForms application that works in 2 modes : Consultation and Modification. When my form is in Consultation mode, I need to set the Enabled property of the MultiColumn ComboBox to false. However, the look of the ComboBox must be the same (White Back COlor with Black text color).

The problem is when I set the property enabled to false, I can't change the properties. The control always has grayish colors (text and border).

How can I set the proper colors to my disabled MultiColumn Combo box?

Thanks in advance

Yves Thibodeau

MultiColumn ComboBox

answered on 18 Nov 2010

1 answer

155 views

Initial Load Time is very slow

I know theming slows down the initialization so is there a way I can disable theming for the entire application?

Thanks

General Discussions

answered on 18 Nov 2010

3 answers

220 views

Rad RibbonBar Form as MDI Container

I have added a rad ribbon bar form and set the isMDIContainter to true. But we i create the child form it loads in memory but does not display in the mdi form. Please guide me how it will. I searched over internet and no help is available.
I shall be very thankful to all members.

Shahzad Ahmed Khan
MIS COORDINATOR

RibbonBar

answered on 18 Nov 2010

1 answer

136 views

Hierarchical gridview problems

Hi All,

In our WinForms application we have some hierarchival gridviews (we call them master-detail grid). This week we upgraded to the new 2010.3 10.1109 version, the last version was the 2010.2 10.914, and the application worked fine with the older verion.

But, now:
In the UserAddedRow event the e.Row.Hierarchilevel is 1 always, and not 0 in the case of new master rows.

In the UserDeletedRow event the e.Row.DataBoundItem is null, so, e.g.: e.Row.DataBoundItem.GetType().Name throws a NullReferenceException.

Any idea?

Best regards,

Peter Szintai

GridView

answered on 17 Nov 2010

13 answers

363 views

Child nodes loaded on demand

I have a situation where I want to create a treeview that has 4 levels. I want to immediately load the first two levels, and only load levels 3 and 4 for a particular level 2 node when it is expanded. I would like all of these nodes to be bound to a datatable(s) for ease of updating the data. What would be the best way to accomplish this? I am experimenting with both related tables in a hierarchy, and a self-referencing table, but haven't seen the exact results I am looking for. Thanks for your help!

Treeview

answered on 17 Nov 2010

4 answers

268 views

RadGridView: Loop over RowInfo: Set Row.IsVisible

Hello,

I just wanted to share this in case anyone else had the same issue.

Scenario
+ RadGridView bound to datasource.
+ Multiselect enabled

Pre Q3 2010 you were able to loop over the rows and set each SelectedRow IsVisible property to False as below

Private Sub RadButton1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles RadButton1.Click

    Try

        Me.Cursor = Cursors.WaitCursor

        For Each row As GridViewRowInfo In Me.RadGridView1.SelectedRows

            row.IsVisible = False

        Next

    Finally

        Me.Cursor = Cursors.Default

    End Try

End Sub

Post Q3, you can only do this if you have only 1 row selected. With multiple rows selected the RadGridView throws an InvalidOperationException (collection was modified) exception.

In order to get over this, one needs to use the BeginUpdate / EndUpdate methods of RadGridView.

The modified code is below:

Private Sub RadButton1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles RadButton1.Click

    Try

        Me.Cursor = Cursors.WaitCursor

        Me.RadGridView1.BeginUpdate()

        For Each row As GridViewRowInfo In Me.RadGridView1.SelectedRows

            row.IsVisible = False

        Next

        Me.RadGridView1.EndUpdate(True)

    Finally

        Me.Cursor = Cursors.Default

    End Try

End Sub

hope someone finds this useful.

Richard

EDIT: Changed the BeginUpdate and EndUpdate to outside of the loop

GridView

answered on 17 Nov 2010

6 answers

180 views

ImageIndex issue

Hello!

I have an issue with assigning the ImageIndex of GridCellElement.

Let’s take a simple code sample. An image list with a single image is assigned to the grid view. All settings are by default.

01.public partial class Form1 : Form

02.{

03. public Form1()

04. {

05. InitializeComponent();

06.

07. for (int i = 0; i < 8; i++)

08. radGridView1.Columns.Add(new GridViewTextBoxColumn());

09.

10. for (int i = 0; i < 8; i++)

11. radGridView1.Rows.Add(radGridView1.Rows.NewRow());

12. }

13.

14. private void radGridView1_CellFormatting(object sender, CellFormattingEventArgs e)

15. {

16. if ((e.CellElement.RowIndex + e.CellElement.ColumnIndex) % 2 == 0)

17. {

18. e.CellElement.ImageIndex = 0;

19. }

20. }

21.}

When I build this sample with “RadControls for WinForms Q3 2009 SP1” it shows the “chessboard”. But when I build it with the latest “RadControls for WinForms Q2 2010 SP2” it shows an empty grid.

To have it running as expected I have to do the following workaround (see line 5):

1.private void radGridView1_CellFormatting(object sender, CellFormattingEventArgs e)

2.{

3. if ((e.CellElement.RowIndex + e.CellElement.ColumnIndex) % 2 == 0)

4. {

5. e.CellElement.ImageIndex = -1;

6. e.CellElement.ImageIndex = 0;

7. }

8.}

So, perhaps this is a bug.

Thank you.

GridView