click on a color button and after button click it will color entire row of cell you click

Try this.. this code will work without a button.. put the code in the sheet module..

Private Sub Worksheet_SelectionChange(ByVal Target As Range)
   Dim Low As Double
   Dim High As Double
   Low = 26     '< change as desired
   High = 47   '< change as desired

   'If the target cell is clear
   If Target.EntireRow.Interior.ColorIndex = xlNone Then

      'Then change the background to a random color
      Target.EntireRow.Interior.ColorIndex = Int((High - Low + 1) * Rnd() + Low)

      'But if the target cell is already the color
   ElseIf Target.EntireRow.Interior.ColorIndex <> xlNone Then

      'Then clear the background color
      Target.EntireRow.Interior.ColorIndex = xlNone

   End If

End Sub