page.login(OAuthProvider) not working on Android after building APK

[gt-diego-pizarro]

Question

Hi everyone,

I’m building a mobile app with Flet, using OAuthProvider for authentication (Auth0 as the provider).

When I run the app with flet run or flet run --ios, everything works perfectly — the login button triggers page.login(provider) and opens the browser to start the Auth0 flow.

However, after building the app with flet build apk and installing it on the Android emulator (through Android Studio), the login button doesn’t do anything. It looks like page.login(provider) isn’t working on Android — the browser window for Auth0 never opens.

Has anyone experienced this issue or found a workaround to make OAuth login work in the Android build?

Thanks in advance!

— Diego

Code sample

class AuthService:
   def _setup_provider(self):
        ...
        code_verifier, code_challenge = self._generate_pkce_pair()
        
        provider = OAuthProvider(
            client_id=AUTH0_CLIENT_ID,
            client_secret="",
            redirect_url=redirect_url,
            authorization_endpoint=f"https://{AUTH0_DOMAIN}/authorize",
            token_endpoint=f"https://{AUTH0_DOMAIN}/oauth/token",
            user_endpoint=f"https://{AUTH0_DOMAIN}/userinfo",
            user_id_fn=lambda u: u.get("sub"),
            scopes=["openid", "profile", "email"],
            code_challenge=code_challenge,
            code_challenge_method="S256",
            code_verifier=code_verifier,
        )
        return provider, logout_url

    def perform_login(self, complete_page_html):
        saved_token = self.get_saved_token()
        self.page.login(
            self.provider,
            saved_token=saved_token,
            complete_page_html=complete_page_html,
        )

# main.py
def main(page: ft.Page):
    page.adaptive = True
    page.theme_mode = settings.theme_mode

    auth = AuthService(page)

    def on_login_success():
        page.controls.clear()
        load_main_app_layout(page, auth)

    def on_logout_success():
        page.controls.clear()
        page.appbar = None
        page.navigation_bar = None
        login_screen = LoginScreen(auth)
        page.add(login_screen)
        page.update()

    auth.set_login_handler(on_login_success)
    auth.set_logout_handler(on_logout_success)

    if not auth.user_is_authenticated():
        page.appbar = None
        page.navigation_bar = None
        login_screen = LoginScreen(auth)
        page.add(login_screen)
    else:
        load_main_app_layout(page, auth)


ft.app(main, view=ft.AppView.WEB_BROWSER)

Error message

No response

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• I have searched for answers to my question both in the issues and in previous discussions.