window.blur - Alert box keeps showing

Question

I want to show an alert box when browser loses focus. So here is my code:

$(window).blur(function(e) {
    alert("Your browser lost focus");
    e.stopPropagation();
});

However, the alert box keep pop up, say when I use Alt+Tab to switch to another window. Can anyone help telling me what is wrong?

are you looking for `e.preventDefault()?` to prevent default action — guradio, Mar 20 '17 at 06:03
Check this out http://stackoverflow.com/questions/5963669/whats-the-difference-between-event-stoppropagation-and-event-preventdefault — shubham agrawal, Mar 20 '17 at 06:08

Koby Douek · Answer 1 · 2017-03-20T06:25:24.213

4

Using $(window).blur - Once an alert window pops, the alert box itself is causing you to lose focus on your browser. This is highly unrecommended.

If you only want to test lose focus, you should use:

 console.log("Your browser lost focus");

Otherwise, do not expose this to the site users - it will cause an infinite loop of alert windows.

edited Mar 20 '17 at 06:25

answered Mar 20 '17 at 06:03

Koby Douek

16,156
19
74
103

2

ProTip: Get out of the habit of using `alert()` for debugging. You'll find `console.log()` and `console.error()` will make your life much better. https://developer.mozilla.org/en-US/docs/Web/API/Console – cloudworks Mar 20 '17 at 06:08

score 0 · Answer 2 · edited Mar 20 '17 at 07:47

0

Try this instead

$('selector').on(eventType, function (event) {
  alert(('cancelable' in event));   //will return true
  alert(event.cancelable);      //will return true if event can be cancelled
  //NOTE: Firefox mistakenly always returns true
});

edited Mar 20 '17 at 07:47

Ankit Kumar Gupta

1,256
1
10
23

answered Mar 20 '17 at 06:05

T-don Terry

1
2

score 0 · Answer 3 · answered Mar 20 '17 at 06:11

0

TRY THIS DEMO, ALERT ON LOST FOCUS, WHEN LOST FOCUS TRIGGER OR CALL ANY ACTION

TRY THIS FIDDLE

answered Mar 20 '17 at 06:11

Alfin Paul

1,543
14
26

window.blur - Alert box keeps showing

3 Answers3