how to bind a custom widget defined in .kv from python

[emsoss]

i need help binding a button widget that was created in .kv. my program worked before but because i was unable to create the lay iout i wanted in python, i had to do it in my .kv file. now i am have a problem binding to it in python. 

here is the .kv file

<widgets>: 

    Button:

        #on_release:print self.ids.name.text

        pos: self.parent.pos

        size: self.parent.size

        StackLayout:

        

            pos: self.parent.pos

            size: self.parent.size

            orientation: 'lr-tb'

            Label:

                id:location

                size_hint: .3,.5

                text: 'self.location'

                text_size:self.size

                halign:'left'

                valign:'middle'

            Label:

                id:name

                size_hint: .5,.5

                text_size:self.size

                text: 'self.text'

                halign:'left'

                valign:'middle'

            Label:

                id:time

                size_hint: .2,.5

                text: 'self.time'

                text_size:self.size

                halign:'left'

                valign:'middle'

            Label:

                id:message

                size_hint:1,.5

                text_size:self.size

                text:'self.message'

                halign:'left'

                valign:'middle'

.py file 

class widgets(Widget):

    pass

class ScreenManagement(ScreenManager,):

      def display(self):

                self.btn=widgets(id=btn_id,background_color=coleur,background_normal='')

                self.btn.ids.time.text=str(self.tim)

                self.btn.ids.name.text=name

                #self.btn.ids.

                self.btn.ids.location.text=room

                self.btn.ids.message.text=own_message

              

                self.btn.bind(on_release=partial(self.btn_pressed,self.btn.id)) # when a user button is pressed call the btn_pressed function

                self.btn.bind(on_release=self.change_screen)

                self.ids.grid.add_widget(self.btn)

                print 'here'

in the above code, replacing     self.btn=widgets(id=btn_id,background_color=coleur,background_normal='')  by self.btn=Button()  makes the binding work.

what i'm missing

[ZenCODE]

Okay, these is too much missing here to try and run it. One thing. Your widget classname should be capitalized. i.e.

    class Widgets(Widget):

Then try making the code runnable and explain exactly what you want to happen.

[emsoss]

here is a runnable code. when the button is pressed, i would like to call a function which changes the screen. now it seem like the binding is not working.

.py file

from kivy.app import App

from kivy.lang import Builder

from kivy.uix.floatlayout import FloatLayout

from kivy.uix.stacklayout import StackLayout

from kivy.uix.button import Button

from kivy.uix.label import Label

from kivy.properties import ObjectProperty

from kivy.factory import Factory

from kivy.app import App

from kivy.uix.scrollview import ScrollView

from kivy.uix.gridlayout import GridLayout

from kivy.uix.button import Button

from kivy.uix.screenmanager import ScreenManager

from kivy.uix.boxlayout import BoxLayout

import redis

from kivy.graphics import Color

from kivy.uix.widget import Widget

class widgets(Widget):

    pass

class ScreenManagement(ScreenManager):

    def change_screen(self,*args):                                    #need to understand this

        App.get_running_app().root.current = 'choice'

    

    def add_btn(self):

        for i in range(10):

            self.btn=widgets(id=str(i))

            self.btn.ids.time.text=str(i)

            self.btn.ids.name.text=str(i)

            self.btn.ids.location.text=str(i)

            self.btn.ids.message.text=str(i)

            #.btn.bind(on_release=partial(self.btn_pressed,self.btn.id)) # when a user button is pressed call the btn_pressed function

            self.btn.bind(on_release=self.change_screen)

            self.ids.grid.add_widget(self.btn)

                

class yourApp(App):

    pass

if __name__ == '__main__':

    yourApp().run()

         

.kv file

<Widgets>: 

    Button:

        pos: self.parent.pos

        size: self.parent.size

        StackLayout:

            padding:(5,5,5,5)

ScreenManagement:   

    Screen:

        BoxLayout:

            orientation:'vertical'

            ScrollView:

                GridLayout:

                    size_hint_y:None

                    row_default_height:100

                    id:grid

                    cols:1

                    Button:

                        on_press:root.add_btn()

        

    Screen:

        name: 'choice'

        canvas:

            Color:

                rgb:0.5,.8,1

            Rectangle:

                pos: self.pos

                size: self.size

        BoxLayout:

        

[emsoss]

i found a way around by doing this in .kv file:   on_press: root.call_back() wherre call_back() is a fx defined in python. i'm still interested in how i could have done the binding in python. 

[ZenCODE]

I get a blank screen when I run your code. Probably because you app does not have a build method?

Anyway, everything you can do it kv you can do in Python. Your python probably did not work because a Widget does not define an 'on_release' event: only a button does. SO inheriting from Widget will not give you an 'on_release' event. You could test that by making your (capitalized) Widgets class inherit from Button, not Widget? But in your code, the Widgets contains a bunch of other widgets, so should rather be layout.

But anyway, you got it working. Play on :-)