title: How to position buttons inside a scrollview using kivy
body: <p>I have some buttons inside a gridlayout in a scrollView that move vertically. I have been trying to postion those buttons at different positions but they are not changing. Please how do I position those buttons at different x and y coordinate. I used floatlayout but it is not working for ScrollView(), why is that?</p>
  <pre><code>import kivy
  kivy.require('1.8.0')
  
  from kivy.app import App
  from kivy.uix.button import Button
  from kivy.uix.scrollview import ScrollView
  from kivy.uix.gridlayout import GridLayout
  
  
  class ScrollViewApp(App):
      def build(self):
  
          grid = GridLayout(cols=2, spacing=90, size_hint=(None,None))   
          grid.bind(minimum_height=grid.setter('height'))
     
  
              btn1=Button(text='1', size=(90,90), size_hint=(None,None), pos_hint={'center_x':.5, 'center_y': 6})
              btn2=Button(text='1', size=(90,90), size_hint=(None,None), pos_hint={'center_x':.5, 'center_y': 2})
              btn3=Button(text='1', size=(90,90), size_hint=(None,None), pos_hint={'center_x':.5, 'center_y':.9})
  
          grid.add_widget(btn1)
           grid.add_widget(btn2)
           grid.add_widget(btn3)
  
  # pos_hint={center_x and center_y} not working 
          scroll = ScrollView( size_hint=(1, 1), do_scroll_x=False, do_scroll_y=True, scroll_type=['content'])
          scroll.effect_cls= 'ScrollEffect'
          scroll.add_widget(grid)
  
          return scroll
  
  
  if __name__ == '__main__':
      ScrollViewApp().run()
  </code></pre>