记录APP一次使用的累计时长

app.vue里，onShow onHide

//App.vue
<script>
export default {
globalData: {
secondCount: 0,
},
data() {
return {
timer: null, // 计时器
};
},
onLaunch() {
console.log('App Launch');
},
onShow() {
console.log('App Show');
this.timer = setInterval(() => {
this.globalData.secondCount++;
}, 1000);
},
onHide() {
clearInterval(this.timer);
this.timer = null;
console.log('App Hide');
},
beforeDestroy() {
clearInterval(this.timer);
this.timer = null;
},
methods: {
watch: function(method, istr) {
var obj = this.globalData;
Object.defineProperty(obj, istr, {
configurable: true,
enumerable: true,
value:second,
set: function(value) {
this.globalData.secondCount = value;
method(value);
},
get: function(value) {
return this.globalData.secondCount;
}
})
}
}
}
</script>

//index.vue
<template>
<view>
</view>
</template>
<script>

export default {  
    data() {  
        return {                  
        }  
    },        
    onLoad() {  
        const App = getApp();  
        console.log("globalData:"+JSON.stringify(getApp().globalData));           
        getApp().watch(this.getWatchCount,"secondCount")  //sumTime是globalData中定义的属性  

    },  
    methods: {  
        getWatchCount(val){  
                console.log('输出变化的值',JSON.stringify(val));  
                //当 sumTime>10 调用方法 handleSumTimeGreaterThan10  
        },  
        handleSumTimeGreaterThan10() {  
              // 处理 secondCount 大于10的情况  
              console.log('secondCount 大于10了！');  
              // 将全局变量sumTime设置0，重新计数  
        }  
    }  
}  

</script>

<style>
</style>

websocket主动发送信息给前端，定时器轮作判断，方案二用户登陆后记录记录当前的时间并且使用定时器每秒监听当前的时间变化并用当前时间减登陆时间是否大于30即可做出提示