I created an app with a NavigationDrawer and everything work correctely, but the problem is to return to the first screen. I want to go back to the first screen (the Screen with name: 'Screen_*principal') when I click in the arrow-left in the MDTopAppBar in Login_*screen but nothing that I did worked.
KV file:
#: import RiseInTransition kivy.uix.screenmanager.RiseInTransition
#: import SlideTransition kivy.uix.screenmanager.SlideTransition
<CustomizeScreen@MDBoxLayout>
orientation: 'vertical'
text: ''
padding: 100
MDLabel:
text: root.text
halign: 'center'
pos_hint: {'center_x': .5}
MDFillRoundFlatButton:
text: 'Regresar'
pos_hint: {'center_x': .5}
on_release:
app.root.current = 'screen_principal'
app.root.transition = SlideTransition(direction= 'left' )
<DrawerClickableItem@MDNavigationDrawerItem>
focus_color: "#e7e4c0"
text_color: "#4a4939"
icon_color: "#4a4939"
ripple_color: "#c5bdd2"
selected_color: "#0c6c4d"
<DrawerLabelItem@MDNavigationDrawerItem>
text_color: "#4a4939"
icon_color: "#4a4939"
focus_behavior: False
selected_color: "#4a4939"
_no_ripple_effect: True
<Screen_principal>:
MDNavigationLayout:
MDScreen:
MDTopAppBar:
title: "Navigation Drawer"
elevation: 4
pos_hint: {"top": 1}
md_bg_color: "#e7e4c0"
specific_text_color: "#4a4939"
left_action_items: [["menu", lambda x: nav_drawer.set_state("open")]]
MDNavigationDrawer:
id: nav_drawer
radius: (0, 16, 16, 0)
MDNavigationDrawerMenu:
MDNavigationDrawerHeader:
title: "LOCATE YOU"
source: "icono.png"
spacing: "4dp"
padding: "12dp", 0, 0, "56dp"
DrawerClickableItem:
icon: "login"
text_right_color: "#4a4939"
text: "Iniciar Sesion"
on_press:
root.manager.current = "Login_screen"
DrawerClickableItem:
icon: "new-box"
text: "Registrarse"
text_right_color: "#4a4939"
on_press:
root.current = "screen_register"
DrawerClickableItem:
icon: "information-outline"
text: "Informacion"
text_right_color: "#4a4939"
on_press:
root.current = "scr1"
DrawerClickableItem:
icon: "microsoft-teams"
text: "Equipo"
text_right_color: "#4a4939"
on_press:
root.current = "scr1"
<Login_screen>:
MDBoxLayout:
orientation: 'vertical'
MDTopAppBar:
title: "Login"
md_bg_color: "#e7e4c0"
left_action_items: [["arrow-left", lambda *args : setattr(screen_manager, "current", "Screen_principal")]]
MDBoxLayout:
orientation: 'vertical'
size_hint_y: 0.3
Image:
source: 'usuario.png'
pos_hint: {'center_x': 0.5}
MDLabel:
text: 'Iniciar Sesion'
halign: 'center'
color: '#FF5A1E'
font_size: '35dp'
bold: True
pos_hint: {'center_y': .5}
MDBoxLayout:
orientation: 'vertical'
size_hint_y: 0.3
spacing: '12dp'
MDTextField:
id: user
hint_text: "Nombre de usuario"
icon_right: "account"
font_size: '25dp'
icon_right_color: '#FF5A1E'
pos_hint: {'center_x': 0.5}
MDTextField:
id: password
password:True
icon_right: "key-variant"
font_size: '25dp'
icon_right_color: '#FF5A1E'
hint_text: "Contrasena"
pos_hint: {'center_x': 0.5}
MDLabel:
id: signal_login
text: ''
halign: 'center'
color: '#FF5A1E'
font_size: '15dp'
MDBoxLayout:
orientation: 'vertical'
size_hint_y:0.4
spacing: '25dp'
MDFillRoundFlatButton:
id: bt_ingresar
text: 'Ingresar'
pos_hint: {'center_x':0.5}
on_release:
x = app.login_data()
root.current = 'open_screen' if x == True else None
MDFillRoundFlatButton:
md_bg_color: 1,1,1,1
Python file:
from kivymd.app import MDApp
from kivy.uix.screenmanager import ScreenManager
from kivy.lang import Builder
from kivy.uix.gridlayout import GridLayout
from kivy.core.window import Window
import requests
from kivy.uix.screenmanager import Screen, ScreenManager
from kivy.properties import BooleanProperty, ObjectProperty
Builder.load_file('diseno.kv')
class Screen_principal(Screen):
pass
class Login_screen(Screen):
pass
class TestApp(MDApp):
def build(self):
# Create the screen manager
sm = ScreenManager()
sm.add_widget(Screen_principal(name='Screen_principal'))
sm.add_widget(Login_screen(name='Login_screen'))
return sm
if __name__ == '__main__':
TestApp().run()
I tried a lot of things but nothing work, if someone could fix it I would be very grateful
In your kv, change:
left_action_items: [["arrow-left", lambda *args : setattr(screen_manager, "current", "Screen_principal")]]
to:
left_action_items: [["arrow-left", lambda *args : setattr(root.manager, "current", "Screen_principal")]]
This change accesses the ScreenManager by referencing root.manager, and the root in that context is the Login_screen.