Android Question Help with accelerometer and imageview

Sub Process_Globals
    Dim Accelerometer As PhoneAccelerometer

End Sub

Sub Globals
    Dim can As Canvas
    Dim srect As Rect
    Dim drect As Rect

    Dim bm As Bitmap
End Sub

Sub Activity_Create(FirstTime As Boolean)

    can.Initialize(Activity)
    bm.Initialize(File.DirAssets,"PANO.jpg")
   
    Dim l As Int = (bm.Width/2)-Activity.Width/2 'left
    Dim r As Int = (bm.Width/2)+Activity.Width/2  'right

    Dim t As Int = (bm.height/2)-Activity.height/2 'top
    Dim b As Int = (bm.height/2)+Activity.height/2  'bottom
   
    'source middle of Panorama
    srect.Initialize(l,t,r,b)
   
    drect.Initialize(0,0, Activity.width, Activity.Height)
   
    can.DrawBitmap( bm, srect,drect)

End Sub

Sub Activity_Resume
    Accelerometer.StartListening("Accelerometer")
End Sub

Sub Activity_Pause (UserClosed As Boolean)
    Accelerometer.StopListening
End Sub

Sub Accelerometer_AccelerometerChanged (X As Float, Y As Float, Z As Float)
    Log (x & " " & Y & " " & Z)

    srect.Left = srect.Left - (y*100)
   
    'avoid negative values of left
    If srect.Left < 0 Then
        srect.Left = 0
        srect.right = Activity.width
        Return
    End If
    srect.right = srect.right -(y*100)
   
    'avoid values > imagewidth for right
    If srect.right > bm.width Then
        srect.Left = bm.width-Activity.Width
        srect.right = bm.width
        Return
    End If
       
    can.DrawBitmap( bm, srect,drect)
    Activity.Invalidate
   
End Sub