使用 h5 新特性，轻松监听任何 App 自带返回键

var
 hiddenProperty =
'hidden'

in
 document ?
'hidden'
 :    

'webkitHidden'

in
 document ?
'webkitHidden'
 :    

'mozHidden'

in
 document ?
'mozHidden'
 :    

null
;

var
 visibilityChangeEvent = hiddenProperty.replace(
/hidden/
i,
'visibilitychange'
);

var
 onVisibilityChange =
function
(){

if
 (document[hiddenProperty]) {    

            console.log(
'页面非激活'
);

        }
else
{

            console.log(
'页面激活'
)

        }

    }

    document.addEventListener(visibilityChangeEvent, onVisibilityChange);