1st way:
it is not the problem to click any element using the same js. As you know how to get any option the last actions remaning is to perform a click.
This should work for you:
WebElement hiddenWebElement =driver.findElement(By(..selector of the element....));
((JavascriptExecutor)driver).executeScript("arguments[0].click()",hiddenWebElement);
2nd way:
String cssSelector= ...//i gave them in your previous question
JavascriptExecutor js = (JavascriptExecutor) driver;
StringBuilder stringBuilder = new StringBuilder();
stringBuilder.append("var x = $(\'"+cssSelector+"\');");
stringBuilder.append("x.click();");
js.executeScript(stringBuilder.toString());
3rd way:
using actions builder, advanced user actions API. You can read about it here
And code will be smth like that:
WebElement mnuElement;
WebElement submnuElement;
mnEle = driver.findElement(By.Id("mnEle")).click();
sbEle = driver.findElement(By.Id("sbEle")).click();
Actions builder = new Actions(driver);
// Move cursor to the Main Menu Element
builder.moveToElement(mnEle).Perform();
// Giving 5 Secs for submenu to be displayed
Thread.sleep(5000L);
// Clicking on the Hidden SubMenu
driver.findElement(By.Id("sbEle")).click();
You can also some additional info here
Hope this somehow helps you)