Gesture to scroll on a RadPageView

[OD]

Hi, 

I currently develop an application on Windows 10 on a tactile device uses a RadPageView (explorerBar mode).

I want to use gesture to control the scroll, i set the enableGesture to Pan.

And in PanGesture event, i have the code :

   

If CType(CType(sender, RadPageView).GetChildAt(0).GetChildAt(3), Telerik.WinControls.UI.RadScrollBarElement).Visibility = ElementVisibility.Visible Then
          If CType(CType(sender, RadPageView).GetChildAt(0).GetChildAt(3), Telerik.WinControls.UI.RadScrollBarElement).Value + e.Offset.Height >= CType(sender, RadPageView).VerticalScroll.Minimum And _
             CType(CType(sender, RadPageView).GetChildAt(0).GetChildAt(3), Telerik.WinControls.UI.RadScrollBarElement).Value + e.Offset.Height <= CType(sender, RadPageView).VerticalScroll.Maximum Then
              CType(sender, RadPageView).VerticalScroll.Value = CType(CType(sender, RadPageView).GetChildAt(0).GetChildAt(3), Telerik.WinControls.UI.RadScrollBarElement).Value + e.Offset.Height
          End If
          CType(CType(sender, RadPageView).GetChildAt(0).GetChildAt(3), Telerik.WinControls.UI.RadScrollBarElement).Value += e.Offset.Height
      End If

Only the scroll bar moves, not the control

 Thanks for your help :)

NB : I'm using Q1-2015

[Dimitar]

Hi ,

Thank you for writing.

You need to call the InvalidateMeasure method in order to properly update the view after the scroll value is set:

Private Sub radPageView1_PanGesture(ByVal sender As Object, ByVal e As Telerik.WinControls.PanGestureEventArgs)
    Dim el As RadPageViewExplorerBarElement = TryCast(Me.radPageView1.ViewElement, RadPageViewExplorerBarElement)

    If el.Scrollbar.IsElementVisible Then
        e.Handled = True
        If e.Offset.Height > 0 AndAlso el.Scrollbar.Value + 10 < el.Scrollbar.Maximum Then
            el.Scrollbar.Value += 10
            el.InvalidateMeasure()
        End If
        If e.Offset.Height < 0 AndAlso el.Scrollbar.Value - 10 >= 0 Then
            el.Scrollbar.Value -= 10
            el.InvalidateMeasure()
        End If
    End If
End Sub

Please let me know if there is something else I can help you with. 

 

Regards,
Dimitar
Telerik

[OD]

Many thanks, works like a charm :)

[Fahmi]

Hi Dimitar,

Could you please provide me the same functionality in C# ( Telerik winforms ).
Thanks,

Fahmi

[Dess | Tech Support Engineer, Principal]

Hello, Fahmi,

You can find below the code in C#:

        private void RadPageView1_PanGesture(object sender, PanGestureEventArgs e)
        { 
            RadPageViewExplorerBarElement el = this.radPageView1.ViewElement as RadPageViewExplorerBarElement;

            if (el.Scrollbar.IsElementVisible)
            {
                e.Handled = true;
                if (e.Offset.Height > 0 && el.Scrollbar.Value + 10 < el.Scrollbar.Maximum)
                {
                    el.Scrollbar.Value += 10;
                    el.InvalidateMeasure();
                }
                if (e.Offset.Height < 0 && el.Scrollbar.Value - 10 >= 0)
                {
                    el.Scrollbar.Value -= 10;
                    el.InvalidateMeasure();
                }
            }
        }

Feel free to use the free Telerik Code Converter if you need any further code converting: https://converter.telerik.com/ 

I hope this information helps.

Regards,
Dess | Tech Support Engineer, Sr.
Progress Telerik