document.addEventListener("visibilitychange", function() {
  console.log( document.visibilityState );
});

    
    
    
    


    
这是第一个标签页

    

window.onblur = () => {
            document.title = "你居然还切屏？？？--tab1"
        }

        window.onfocus = () => {
            document.title = "好吧，你回来了--tab1"
        }

	let isCut = false
        let lastTime;

	function recordTime() {
            isCut = true
            lastTime = Date.now()
        }

        function showTimeDiff() {
            if (isCut) {
                let timeDiff = (Date.now() - lastTime) / 1000;
                // alert(`你切屏出去${timeDiff}`)
                console.log(timeDiff);
                isCut = false
            }
        }

function countTimes() {
            let store = window.sessionStorage.getItem('leave-times')
            if( store === null) {
                window.sessionStorage.setItem('leave-times', 0)
                return
            }
            store ++;
            window.sessionStorage.setItem('leave-times' , store);
        }