javascript - Detecting tab visibility in Firefox - Stack Overflow

admin管理员组

文章数量:1386773

I'm writing a webapp that performs an action every minute or so which (very briefly) hangs the browser. I'd like to pause this action when the tab displaying the webapp is not shown, to minimize the annoyance. Is there any way to do this using Javascript, under the latest version of Firefox?

Edit: to clarify, I'm asking about how to determine the visibility of the tab that some JS code is running in - not how to pause/resume the action which hangs the browser.

I'm writing a webapp that performs an action every minute or so which (very briefly) hangs the browser. I'd like to pause this action when the tab displaying the webapp is not shown, to minimize the annoyance. Is there any way to do this using Javascript, under the latest version of Firefox?

Edit: to clarify, I'm asking about how to determine the visibility of the tab that some JS code is running in - not how to pause/resume the action which hangs the browser.

• javascript
• firefox
• tabs

Share Improve this question Follow edited Dec 3, 2009 at 16:51 Matt Ball asked Dec 3, 2009 at 16:39 Matt BallMatt Ball 360k102102 gold badges653653 silver badges720720 bronze badges

Add a ment  | 

3 Answers 3

Sorted by: Reset to default 7

var isFocused = true;

window.onblur=function(){
  if(isFocused==true){
    isFocused=false;
  }
}

window.onfocus = function(){
  isFocused = true;
}

Now, that action you perform, every minute or two, do it only when isFocused is true. That is when the tab of your page/webapp is focused.

Not tested, but how about this:

window.onblur() = function () { ... pause your script here }

I don't know if Firefox handles the window blur in tabs as separate windows.

I believe you will need to make do with the window.onblur event, because accessing the browser window from a script in a webpage is forbidden for security reasons (only allowed for privileged scripts).

What you want to do (access the browser window from within a child window or a webpage) is described in Mozilla Developer Center, but it does mention there that only a privileged script can do it, and you'll probably get a "Premission denied" error when you try.

本文标签： javascriptDetecting tab visibility in FirefoxStack Overflow