workaround for kivy gridlayout problem

gloproblem.py

from kivy.uix.gridlayout import GridLayout
from kivy.uix.label import Label
from kivy.uix.image import Image

from kivy.app import Builder, App
from random import randint
from kivy.uix.stacklayout import StackLayout
from pygments.formatters import img

Builder.load_string("""
<GridLayout>:
    canvas:
        Color:
            rgba: 1,0,0,1
        Line:
            rectangle: self.x+1,self.y+1,self.width-1,self.height-1
<Image>:
    canvas:
        Color:
            rgba: (0,1,0,0.3)
        Rectangle:
            pos: self.pos
            size: self.size
            
<Label>:
    size_hint: None,None
    text_size: self.width, None
    height: self.texture_size[1]
    
""")


class ACListEntry(StackLayout):
    def __init__(self, **kwargs):
        super(ACListEntry, self).__init__(size_hint_y=None, **kwargs)
        self.bind(minimum_height = self.setter("height"))

        img = Image(size_hint = (None,None), size = (60,60), source = "")
        self.add_widget(img)

        lbl = Label(text="TEST layout problem fds af dfsad fsd asdfs adfsad fdsf "*randint(1,6))
        self.add_widget(lbl)
        
        #crappy workaround below
        self.img = img
        self.lbl = lbl
        self.bind(width = self.workaround) 
        
    def workaround(self,_,w):
        self.lbl.width = self.width-self.img.width
        
    #end of crappy workaround
        
class MyApp(App):
    def build(self):

        mainlayout = GridLayout(cols=1)
        
        for _ in xrange(5):
            mainlayout.add_widget(ACListEntry())
        
        return mainlayout


MyApp().run()