The method sendKeys appears (CharSequence []) use sendKey method in the type WebElement is not applicable for the arguments (String) error

. 1  Package SeleniumTestProject;
 2  
. 3  Import the java.util.Timer;
 . 4  Import org.openqa.selenium *. ;
 . 5  Import org.openqa.selenium.chrome.ChromeDriver;
 . 6  Import org.yaml.snakeyaml.events.Event.ID;
 . 7  
. 8  public  class to Test01 {
 . 9      protected String WebUrl = "https://caiyun.feixin.10086.cn/";    // store the URL 
10      public the WebDriver driver;                                        // define a field driver
 11      // initialize browser driver 
12     public void InitDriver() {
13         System.setProperty("webdriver.chrome.driver", "C:\\Users\\Administrator\\AppData\\Local\\Google\\Chrome\\Application\\chromedriver.exe");
14         driver = new ChromeDriver();
15         driver.get(WebURL);
16         driver.manage().window().maximize();
17         String title = driver.getTitle();
18         System.out.print(title);
19     }
20     public void InputBox() {
21         driver.findElement(By.id("account")).sendKeys("15875303116");
22     }
23     public static void main(String[] args){
24         Test01 t = new Test01();
25         t.InitDriver();
26         
27 
28     }
29 }

When using the default configuration of the eclipse to compile this code, 21 lines sendKeys error method, suggesting The method sendKeys (CharSequence []) in the type WebElement is not applicable for the arguments (String), later checked, the problem is the compiler right-package project, click Build Path inside the Configure Build Path , change the Java Compiler in the Compiler compliance level to 1.7 (shown below), click after the application can be solved