title: kivy scrollview inside gridlayout on label
body: <p>I trying to create a one screen app with one root rule set. by pressing a button i should see a scrollable text in the grid next to the button. In all the example solutions I see that scrollview is working in similar KV files that I have seen in other questions. Could someone please identify what I have missed in KV file.</p>
  
  <p>my .py file:</p>
  
  <pre><code>import kivy
  import string
  from kivy.app import App
  from kivy.uix.widget import Widget
  from kivy.uix.label import Label
  from kivy.uix.button import Button
  from kivy.uix.boxlayout import BoxLayout
  from kivy.uix.gridlayout import GridLayout
  from kivy.properties import ObjectProperty
  from kivy.properties import StringProperty
  from kivy.uix.scrollview import ScrollView
  from kivy.core.window import Window
  
  class RootContainer(BoxLayout):
      instance = ObjectProperty(None)
  
      def __init__(self, **kwargs):
          super(RootContainer, self).__init__(**kwargs)
  
      def clickAction1(self, instance):
          #identify the button pressed
          buttonText = instance.text
          self.lbl1.text = instance.text + " some text goes here ... "
          myresult = " this is scrolling text.\n " * 30
          self.lbl5.text = myresult
  
  class MBApp(App):
      def build(self):
          return RootContainer()
  
  
  if __name__ == '__main__':
      MBApp().run()
  </code></pre>
  
  <p>my KV file:</p>
  
  <pre><code>#:kivy 1.0.9
  &lt;RootContainer&gt;:
      id: theRoot
      lbl1: my_labelC
      lbl5: my_labelCS
  BoxLayout:
      orientation: 'vertical'
      spacing: 20
      padding: 20
      canvas: 
          Color: 
              rgb: 0, .33, 0 
          Rectangle: 
              pos: self.pos 
              size: self.size
      Button:
          text: "This is 1st button"
          text_size: self.size
          size_hint: (.5,1)
          on_press: theRoot.clickAction1(self)
      Button:
          text: "This is 2nd button"
          text_size: self.size
          size_hint: (.5,1)
          on_press: root.clickAction1(self)
  
  GridLayout:
      rows: 2
      cols: 1
      spacing: 10
      padding: 10
      canvas: 
          Color: 
              rgb: .7, .63, 0  
          Rectangle: 
              pos: self.pos 
              size: self.size
      Label:
          id: my_labelC
          canvas.before:
              Color:
                  rgb: 0,0,0
              Rectangle:
                  pos: self.pos
                  size: self.size
          text: "Header text for button clicked ......."
          text_size: self.size
      ScrollView:
          GridLayout:
              cols:1
              rows:1
              height: self.minimum_height
              Label:
                  id: my_labelCS
                  text: "Scrolling text goes here ....."
  </code></pre>
  
  <p>I hope this is not a duplicate. Any other suggestions to code are also welcome. Thank you.</p>