how to get smartphone like scrolling for a winforms touchscreen app ( scrolling panel )

Question

After scouring the articles online I have come up with this design for a winforms based touchscreen app that needs smartphone like scrolling. The app itself will run on a ta

Answer 1

This solution seems to be the best one out there and the most commonly accepted one - however, if you scroll to the bottom and touch a the actual flowcontrol behind the buttons (I tried to make this so that there would be empty space), you then have to double tap-and-hold the button for the scrolling to resume. Restarting the application restores the phone-like scrolling functionality. I am wondering if anyone else has seen this or figured it out - try it with your apps and see if it is the case as well. I modified the snippet above so that you can start a new project, copy and paste this into form1's code, and hit run.

   Public Class Form1
        Dim FlowPanel As New FlowLayoutPanel
        Private Function GenerateButton(ByVal pName As String) As Button
            Dim mResult As New Button
            With mResult
                .Name = pName
                .Text = pName
                .Width = 128
                .Height = 128
                .Margin = New Padding(0)
                .Padding = New Padding(0)
                .BackColor = Color.CornflowerBlue
                AddHandler .MouseDown, AddressOf Button_MouseDown
                AddHandler .MouseMove, AddressOf Button_MouseMove
            End With

            Return mResult
        End Function



        Private Sub Form1_Load(ByVal sender As Object, ByVal e As EventArgs) Handles MyBase.Load

            Me.Width = 806
            Me.Height = 480
            FlowPanel.Padding = New Padding(0)
            FlowPanel.Margin = New Padding(0)
            ' FlowPanel.ColumnCount = Me.Width / (128 + 6)
            FlowPanel.Dock = DockStyle.Fill
            FlowPanel.AutoScroll = True
            Me.Controls.Add(FlowPanel)
            Dim i As Integer
            For i = 1 To 98
                FlowPanel.Controls.Add(GenerateButton("btn" & i.ToString))
            Next
        End Sub

        Dim myMouseDownPoint As Point
        Dim myCurrAutoSMouseDown As Point
        Private Sub Button_MouseDown(ByVal sender As Object, ByVal e As MouseEventArgs)
            myMouseDownPoint = PointToClient(Cursor.Position)
            myCurrAutoSMouseDown = FlowPanel.AutoScrollPosition
        End Sub

        Private Sub Button_MouseMove(ByVal sender As Object, ByVal e As MouseEventArgs)
            If e.Button = Windows.Forms.MouseButtons.Left Then
                Dim mLocation As Point = PointToClient(Cursor.Position)
                If myMouseDownPoint <> mLocation Then
                    Dim mCurrAutoS As Point
                    Dim mDeslocation As Point = myMouseDownPoint - mLocation
                    mCurrAutoS.X = Math.Abs(myCurrAutoSMouseDown.X) + mDeslocation.X
                    mCurrAutoS.Y = Math.Abs(myCurrAutoSMouseDown.Y) + mDeslocation.Y

                    FlowPanel.AutoScrollPosition = mCurrAutoS

                End If
            End If
        End Sub
    End Class