Persistent Data with Javascript

Question

Hi,

I have an application that has a "parent" window. In the parent window there are menu items, like the following (using PHP here):

// sample link
echo "<li><a href=\"#\" onclick=openurl('covershift.php');>Shift Coverage</a></\
li>";

// logout link
echo "<li><a href=\"#\" onclick=openurl('logout');>Logout</a></li>";

Each link opens the appropriate page in a different "child" window. When the parent closes all of the child windows must close. I have implemented this functionality with Javascript, here is the function:

var childWindow = new Array();
var windowCount = 0;
function openurl(url)
{
  if(url != 'logout') {
    childWindow[windowCount]=window.open(url,'_blank','height=600,width=800,scr\
ollbars=1');
    windowCount++;
    if (window.focus) {
      childWindow.focus();
    }
  } else {
    var iCount;
    for (iCount=0; iCount < windowCount; iCount++) {
      if ((childWindow[iCount] != null) && !(childWindow[iCount].closed)) {
        childWindow[iCount].close();
      }
    }
    window.location='logout.php';
  }
}

Here is my problem, when a user reloads the parent window and then clicks logout, the child windows remain open. This makes sense as the childWindow array is lost when the parent reloads.

How can I make the childWindow array persistent through a reload?

Thanks!

Answer 1

I don't think you can make a JavaScript object persist through a window load. Instead, could you make an unload event handler that closes your pages?

window.onunload = myCloseFunction;
function myCloseFunction()
{
    // Just copying your code...
    var iCount;
    for (iCount=0; iCount < windowCount; iCount++) {
      if ((childWindow[iCount] != null) && !(childWindow[iCount].closed)) {
        childWindow[iCount].close();
      }
    }
}

Another option might be to have the child windows poll for the existence of the parent.

In the child window:

// Checks every 1 second for valid window.opener
var parentChecker = setInterval(function(){
    if(!opener){
        // Is this good practice?  I don't know!
        clearInterval(parentChecker);
        window.close();
    }
}, 1000);