Question

I’m new to Javascript and I’m trying to make the following code scan to see if a textbox with an id=”lessonNum” is active, if it is not i would like to send a .click to a submit button with an id=”A” when I press ‘a’ on the keyboard. Right now when I select the textbox I get an alert, but when I don’t have it selected it doesn’t pick up my keydown. Please Help!

function GetActive () {

    if (document.activeElement.id == 'lessonNum') {
        alert('lessonNum is active');
        var b1=new Boolean(1);

    } else {
       var b1=new Boolean(0);
    }
}

document.addEventListener("keydown", keyDownTextField, false);

function keyDownTextField(e) {
    var keyCode = e.keyCode;

    if(keyCode==65) {

        if(b1==0) {
            alert('a has been pressed');
            document.getElementById('A').click();
        } 
    }
}

Answer 1

In your code:

> function GetActive () {
>     if (document.activeElement.id == 'lessonNum') {
>         alert('lessonNum is active');
>         var b1 = new Boolean(1);

the above line creates a local variable called b1 and assigns a new boolean object. I think you just want a primitive, so:

    var b1 = true;

or the whole if..else statement can be replaced with:

    var b1 =  document.activeElement.id == 'lessonNum';
    if (b1) alert('lessonNum is active');

Note that getActive is never called so b1 is never set anyway.

In keyDownTextField you have:

> if(b1==0) {
>     alert('a has been pressed');

however b is local to GetActive so a reference error will be thrown. The simple solution is to make b global, a little more work but better though to hold it in a closure.

e.g.

(function(global) {
  var b1;
  var getActive = function () {
    b1 = document.activeElement && document.activeElement.id == 'lessonNum';

    if (b1) alert('lessonNum is active');
  }
  global.getActive = getActive;


  var keyDownTextField = function (e) {
    e = e || window.event;
    var keyCode = e.keyCode || e.which;

    if (keyCode == 65) {
        getActive();  // should it be called here?

        if (b1) {
            alert('a has been pressed'); 
            document.getElementById('A').click();
        }
    }
  }
  global.keyDownTextField = keyDownTextField;
}(this)); 

window.onload = function() {
  addEvent(document, 'keydown', keyDownTextField);
};

// Just a helper    
function addEvent(el, evt, fn){
  if (el.addEventListener) {
    el.addEventListener(evt, fn, false);
  } else if (el.attachEvent) {
    el.attachEvent('on' + evt, fn);
  }
}