Android Question Java Code not working

#If Java
import android.widget.ListView;
import android.view.View;
    public static int topLv(ListView mListView) {
        int index = mListView.getFirstVisiblePosition();
        View v = mListView.getChildAt(0);
        int top = (v == null) ? 0 : (v.getTop());
        return top;
    }
#End If

mListView.getChildAt(index);

#Region  Project Attributes
    #ApplicationLabel: B4A Example
    #VersionCode: 1
    #VersionName:
    'SupportedOrientations possible values: unspecified, landscape or portrait.
    #SupportedOrientations: unspecified
    #CanInstallToExternalStorage: False
#End Region

#Region  Activity Attributes
    #FullScreen: False
    #IncludeTitle: True
#End Region

Sub Process_Globals
    'These global variables will be declared once when the application starts.
    'These variables can be accessed from all modules.

End Sub

Sub Globals
    'These global variables will be redeclared each time the activity is created.
    'These variables can only be accessed from this module.
Private lv As ListView
Private selectedItemPos As Int = -1
Private selectedItemValue As Object
Private lasttoucheditem As Int

End Sub

Sub Activity_Create(FirstTime As Boolean)
    'Do not forget to load the layout file created with the visual designer. For example:
    'Activity.LoadLayout("Layout1")
    lv.Initialize("lv")
    Activity.AddView(lv,0,0,100%x,100%y)
 
    For i = 0 To 100
        lv.AddSingleLine("item : " & i)
    Next
 
    Dim ref As Reflector
    ref.Target = lv
    ref.SetOnTouchListener("lv_Touch")
End Sub

Sub lv_ItemLongClick (Position As Int, Value As Object)
    selectedItemPos = Position
    selectedItemValue = Value
End Sub

Private Sub lv_Touch (o As Object, ACTION As Int, x As Float, y As Float, motion As Object) As Boolean
    If ACTION = 0 Then
        lasttoucheditem = Floor(y/lv.SingleLineLayout.ItemHeight)
    Else if ACTION = 2 Then
        If selectedItemPos > -1 Then
            If Floor(y/lv.SingleLineLayout.ItemHeight) <> lasttoucheditem Then
                lasttoucheditem = Floor((y+getfirstitemtop)/lv.SingleLineLayout.ItemHeight)
                updateLV(lasttoucheditem)          
            End If
        End If
    else if ACTION = 1 Then
        selectedItemPos = -1
    End If
    Return False
End Sub

Sub getfirstitemtop As Int
     Dim jo As JavaObject
     jo.InitializeContext
     Dim pos As Int = jo.RunMethod("topLv",Array(lv))
     Log(pos)
     Return Abs(pos)
End Sub
'
#If Java
import android.widget.ListView;
import android.view.View;
    public static int topLv(ListView mListView) {
        View v = mListView.getChildAt(0);
        int top = (v == null) ? 0 : (v.getTop());
        return top;
    }
#End If

Sub updateLV(pos As Int)
    Dim l As List
    l.Initialize
    For i = 0 To lv.Size-1
        Dim item As Object = lv.GetItem(i)
        l.Add(item)
    Next
    lv.Clear
 
    l.RemoveAt(selectedItemPos)
    l.InsertAt(pos+getfirstvisibleItem,selectedItemValue)
    selectedItemPos = pos+getfirstvisibleItem
 
    For j = 0 To l.Size-1
        lv.AddSingleLine(l.Get(j))
    Next
End Sub

Sub getfirstvisibleItem As Int
    Try
        Dim ref As Reflector
        ref.Target = lv  
        Return(ref.RunMethod("getFirstVisiblePosition"))
    Catch
        Return(0)
    End Try
End Sub

Sub Activity_Resume

End Sub

Sub Activity_Pause (UserClosed As Boolean)

End Sub