Set ScrollBar.LargeChange on SfDataGrid

[James Randle]

Hi,

I have a requirement where I need to change the number of rows that are scrolled down/up when clicking on the vertical scrollbar for the SfDataGrid.

Currently, if I have, say 10 records in view, and I click the scrollbar under the slider, the SfDataGrid moves down 9 records. I want to move down 10 rows at a time so that each click shows 10 new records, rather than 9 new records and one from the previous set of records. I have tried the following code but it doesn't seem to have any effect...

        private void SfDataGrid_FilterItemsPopulated(object sender, Syncfusion.UI.Xaml.Grid.GridFilterItemsPopulatedEventArgs e)

        {

            ScrollViewer scrollViewer = sfDataGrid.GetVisualContainer().ScrollOwner;

            ScrollBar verticalScrollBar = scrollViewer.Template.FindName("PART_VerticalScrollBar", scrollViewer) as ScrollBar;

            verticalScrollBar.LargeChange = 240;

        }

Cheers,

James.

---

Just want to add that changing the value '240' to any other value makes no difference!

[James Randle]

Hi,

Any word on how to accomplish this requirement?

Cheers,

James.

[Shobika Palani]

Hi James, 

Thank you for contacting Syncfusion Support. 

We have analyzed your query to scroll multiple rows on clicking Up/Down in vertical scrollbar. You can achieve this requirement using VisualContainer.LineUp/VisualContainer.LineDown methods as like below code snippet 

private void AssociatedObject_Loaded(object sender, System.Windows.RoutedEventArgs e) 

        { 

            this.AssociatedObject.GetVisualContainer().ScrollOwner.PreviewMouseLeftButtonDown += ScrollOwner_PreviewMouseLeftButtonDown; 

        } 

 

        private void ScrollOwner_PreviewMouseLeftButtonDown(object sender, System.Windows.Input.MouseButtonEventArgs e) 

        { 

            RepeatButton repeatButton = null; 

            object value = null; 

            var source = e.OriginalSource; 

            while (repeatButton == null && source != null) 

            { 

                var parent = source.GetType().GetProperty("InternalVisualParent", BindingFlags.Instance | BindingFlags.NonPublic); 

                value = parent.GetValue(source); 

                source = value; 

                repeatButton = value as RepeatButton; 

            } 

 

            if (repeatButton != null) 

            { 

                var name = ((RoutedCommand)repeatButton.Command).Name; 

                if (name == "LineUp") 

                { 

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

                        this.AssociatedObject.GetVisualContainer().LineUp(); 

                } 

                else if (name == "LineDown") 

                { 

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

                        this.AssociatedObject.GetVisualContainer().LineDown(); 

                } 

            } 

        } 

Please find sample for the same from below link 

Sample Link: 

http://www.syncfusion.com/downloads/support/forum/140767/ze/SfDataGridDemo1554825726  

Please let us know if you need further assistance on this. 

Regards, 

Shobika. 

[James Randle]

Hi,

Thanks for your reply.

That works if i click the up and down arrow buttons, but I would also like to have the same functionality if i click the area between the scrollbar slider and the up/down arrow buttons (see attached file for explanatory image).

Cheers,

James.

Attachment: ClickScrollbar_7dd6799f.zip

[Jayaleshwari N]

Hi James,  

 

We have checked the query “To scroll multiple rows on clicking area between Up/Down arrows in vertical scrollbar”. You can achieve your requirement by calling VisualContainer.LineUp/VisualContainer.LineDown methods for PageUp and PageDown repeat button. 

  

private void ScrollOwner_PreviewMouseLeftButtonDown(object sender, System.Windows.Input.MouseButtonEventArgs e)  

        {  

            RepeatButton repeatButton = null;  

            object value = null;  

            var source = e.OriginalSource;  

            while (repeatButton == null && source != null)  

            {  

                var parent = source.GetType().GetProperty("InternalVisualParent", BindingFlags.Instance | BindingFlags.NonPublic);  

                value = parent.GetValue(source);  

                source = value;  

                repeatButton = value as RepeatButton;  

            }  

  

            if (repeatButton != null)  

            {  

                var name = ((RoutedCommand)repeatButton.Command).Name; 

               if (name == "LineUp" || name=="PageUp") 

                { 

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

                        this.AssociatedObject.GetVisualContainer().LineUp(); 

                    e.Handled = true; 

                } 

                else if (name == "LineDown" || name=="PageDown") 

                { 

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

                        this.AssociatedObject.GetVisualContainer().LineDown(); 

                    e.Handled = true; 

                }             

   }          

}  

 

We have attached the modified sample for your reference and you can download the same from the following location. 

 

Sample Link: http://www.syncfusion.com/downloads/support/forum/140797/ze/SfDataGrid_ScrollingDemo-1068433092  

 

Please let us know if you would require further assistance. 

 

Regards,  

Jayaleshwari N.