Extending PageObject using PageFactory for WebElementFacade

[cbaquero-ar]

I'm trying to use PageFactory within a PageObject extending class, but I get a NullPointerException when trying to access a WebElementFacade. Is there any example with PageObjets that you can refer with the complete code of a working PageObject child class?
Here is mine:
`package pageobjects;

import exceptions.InvalidCredentialsLoginException;
import javafx.util.Duration;
import net.serenitybdd.core.annotations.findby.FindBy;
import net.serenitybdd.core.pages.PageObject;
import net.serenitybdd.core.pages.WebElementFacade;
import net.thucydides.core.annotations.At;
import net.thucydides.core.annotations.DefaultUrl;
import net.thucydides.core.annotations.WhenPageOpens;
import org.openqa.selenium.NoSuchElementException;
import org.openqa.selenium.support.PageFactory;

import java.time.temporal.ChronoUnit;
import java.time.temporal.TemporalUnit;
import java.util.concurrent.TimeUnit;

@DefaultUrl("http://automation.sgh-os.10.125.125.74.nip.io/auth/login")
@at(urls={"#HOST/auth/login"})
public class LoginPage extends PageObject {

@FindBy(xpath = ".//input[@formcontrolname='username']")
public WebElementFacade user;
@FindBy(xpath = ".//input[@formcontrolname='password']")
private WebElementFacade password;
@FindBy(xpath = ".//*[@translate='auth.login.form.SUBMIT']")
private WebElementFacade loginButton;

@FindBy(xpath = "//p[contains(@class,'ng-star-inserted')]")
private WebElementFacade errorMessage;

public LoginPage() {
    super();
    open();
}

@WhenPageOpens
public void waitUntilPageLoads() {
    setWaitForTimeout(30000);
    user.waitUntilVisible();
    element(password).waitUntilVisible();
    element(loginButton).waitUntilVisible();
}

}
`

The error I get is:
net.serenitybdd.core.pages.UnableToInvokeWhenPageOpensMethods: Could not execute @WhenPageOpens annotated method: null at net.serenitybdd.core.pages.PageObject.callWhenPageOpensMethods(PageObject.java:954) at net.serenitybdd.core.pages.PageObject.initializePage(PageObject.java:888) at net.serenitybdd.core.pages.PageObject.open(PageObject.java:883) at net.serenitybdd.core.pages.PageObject.open(PageObject.java:869) at pageobjects.LoginPage.<init>(LoginPage.java:34) at starter.cucumber.steps.LoginSteps.iLoginAs(LoginSteps.java:21) at ✽.I login as 'AUTOAdmin'(file:///C:/Users/baque/Documents/Trabajo/Lamansys/Proyectos/serenity-cucumber-poc/src/test/resources/features/Login.feature:4) Caused by: java.lang.NullPointerException at pageobjects.LoginPage.waitUntilPageLoads(LoginPage.java:40) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498)

[wakaleo]

Try removing the constructor.

[cbaquero-ar]

If I remove the constructor and the call to "open()" method, the browser doesn't start at all. I removed the constructor and moved the open() method outside, but again it gives me the error (NullPointerException when trying to use the WebElementFacade instance).
If I do not have a @WhenPageOpens method, but just call open() and then try to access the WebElementFacade instance, is the same issue.
Any other ideas?

[wakaleo]

You can call the open() method but don't do it in the constructor - that will interfere with the Serenity lifecycle.

[cbaquero-ar]

I found my error: I was calling LoginPage constructor on the Cucumber Step. Removed the constructor and the call to it, then directly used loginPage.open(). Now I can use both WebElement and WebElementFacade with the @FindBy annotation.

Thank you very much!