Crossbrowser & lightweight way to check if user is looking at the page or interacting with it.
From npm
npm install ifvisible.js --save
From Bower
bower install ifvisible.js
For Meteor
mrt add ifvisible
meteor package is provided by @frozeman via Atmosphere
// If page is visible right now
if( ifvisible.now() ){
// Display pop-up
openPopUp();
}
// You can also check the page status
// using `now` method
if( !ifvisible.now('hidden') ){
// Display pop-up if page is not hidden
openPopUp();
}
// Possible statuses are:
// idle: when user has no interaction
// hidden: page is not visible
// active: page is visible and user is active
Handle tab switch or browser minimize states
ifvisible.on("blur", function(){
// example code here..
animations.pause();
});
ifvisible.on("focus", function(){
// resume all animations
animations.resume();
});
ifvisible.js can handle activity states too, such as being IDLE or ACTIVE on the page
ifvisible.on("idle", function(){
// Stop auto updating the live data
stream.pause();
});
ifvisible.on("wakeup", function(){
// go back updating data
stream.resume();
});
Default idle duration is 60 seconds but you can change it with setIdleDuration
method
ifvisible.setIdleDuration(120); // Page will become idle after 120 seconds
You can manually trigger status events by calling them directly or you can set events with their names by giving first argument as a callback
ifvisible.idle(); // will put page in a idle status
ifvisible.idle(function(){
// This code will work when page goes into idle status
});
// other methods are
ifvisible.blur(); // will trigger idle event as well
ifvisible.idle();
ifvisible.focus(); // Will trigger wakeup event as well
ifvisible.wakeup();
You can use ifvisible.off() to remove event triggers:
ifvisible.off('idle', triggeredFunction); // will remove only triggeredFunction from being tiggered on idle
ifvisible.off('idle'); // will remove all events triggered on idle
// works with other events:
ifvisible.off('blur');
ifvisible.off('wakeup');
ifvisible.off('focus');
You can set your smart intervals with ifvisible.js, if user is IDLE or not seeing the page the interval will automatically stop itself
// If page is visible run this function on every half seconds
ifvisible.onEvery(0.5, function(){
// Do an animation on the logo only when page is visible
animateLogo();
});
It's MIT, Go crazy.