Webdriver中PageFactory的正确用法

以博客园登录、退出为例：

下面是LoginPage的源码：

public class LoginPage {
    private WebDriver driver;

    @FindBy(how = How.ID, id = "input1")
    private WebElement userName;
    @FindBy(how = How.ID, id = "input2")
    private WebElement passWord;
    @FindBy(how = How.ID, id = "signin")
    private WebElement loginButton;

    public  LoginPage(WebDriver driver)
    {
        this.driver = driver;
        PageFactory.initElements(driver,this);       PageFactory.initElements一般放在自己的构造函数中，这样别的类调用的时候能保证每次都调用成功。
    }

    public void login(String username, String password)
    {
        userName.clear();
        passWord.clear();
        userName.sendKeys(username);
        passWord.sendKeys(password);
        loginButton.click();
        driver.manage().timeouts().implicitlyWait(3, TimeUnit.SECONDS);
    }

}

下面是Mainpage的代码：

public class MainPage {
    private WebDriver driver;

    @FindBy(how = How.LINK_TEXT, linkText = "登录")
    WebElement loginLink;

    @FindBy(how = How.LINK_TEXT, linkText = "退出")
    WebElement logoutLink;

    public MainPage(WebDriver driver)
    {
        this.driver = driver;
        PageFactory.initElements(driver,this);  
    }

    public void openMainPage(String url)
    {
        driver.get(url);
        //loginLink = driver.findElement(By.linkText("登录"));
        //logoutLink = driver.findElement(By.linkText("退出"));
    }

    public void login(String userName, String passWord)
    {
        loginLink.click();
        WebDriverWait wait = new WebDriverWait(driver,300);
        wait.until(ExpectedConditions.visibilityOfElementLocated(By.id("input1")));

        LoginPage loginPage = new LoginPage(driver);
        loginPage.login(userName,passWord);
    }

    public void logout()
    {
        logoutLink.click();

        LogoutPage logoutPage = new LogoutPage(driver);
        logoutPage.logout();
    }
}

下面是测试用的TestPage的代码：

public class TestPage {

    WebDriver driver;

    @BeforeTest
    public void setUp()
    {
        ChromeOptions options = new ChromeOptions();
        options.addArguments("--start-maximized", "allow-running-insecure-content", "--test-type");
        options.addArguments("--user-data-dir="+System.getenv("USERPROFILE")+"/AppData/Local/Google/Chrome/User Data/Default");
        System.setProperty("webdriver.chrome.driver", "C:\\Selenium\\chromedriver.exe"); //先设置这个
        driver = new ChromeDriver(options);//再选择浏览器
    }
    @Test
    public void testMainPage() throws Exception
    {
        //MainPage mainPage = PageFactory.initElements(driver,MainPage.class);
        MainPage mainPage =new MainPage(driver);    有些人把PageFactory放在这里调用，其实是不合理的，这样容易漏掉LoginPage里的PageFactory
        mainPage.openMainPage("http://www.cnblogs.com");
        mainPage.login("WebdriverTest","Password123!");
        mainPage.logout();
    }
}