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JavaScript

Posted by Sharik M
Sharik M
Courses Plus Student 2,217 Points

JavaScript: Need to Create a timer in Popup window which stops when the window is minimized.

Hello Everyone!! I need to create a timer box in a popup window which will run only when the window is active and will stop when the window is minimized/not active, can anyone please help me in doing the same.

2 Answers

Steven Parker
Steven Parker
242,796 Points
Steven Parker
Steven Parker
242,796 Points

You may be able to use the visibilitychange event.

I'm guessing you already know how to manage your timer and you only need to know when the window is minimized and restored.

You can create an event handler for the "visibilitychange" event on the document, and then test the boolean property document.hidden to see what kind of change occurred. But bear in mind that minimizing is not the only cause of being "hidden", switching browser tabs would do the same thing (but perhaps you want to react the same way them also).

Sharik M
Sharik M
Courses Plus Student 2,217 Points

Thanks Steve, i think this event should be able to resolve my issue, ill keep you guys posted...:-)Cheers!!

Sharik M
PLUS
Sharik M
Courses Plus Student 2,217 Points
Sharik M
Sharik M
Courses Plus Student 2,217 Points

Just an update,I resolved it by using window.onfocus() and window.blur() events which are already part of JavaScript event library.

Steven Parker
Steven Parker
242,796 Points
Steven Parker
Steven Parker
242,796 Points

That's great if it works for you, but that's not quite the same thing.

The blur event will fire anytime you click outside of the window, such as to another window even if it does not obscure the first one. And at that point it will not fire when you minimize the window. There are similar differences in the "focus" behavior.

I'm not sure what you mean by "already part of JavaScript event library", isn't "visibilitychange" also? But be sure to use it with addEventListener as the ononvisibilitychange property may not be widely browser-supported.