app.onPageNotFound事件手机上不触发

我这边测试时发现app.js中的onPageNotFound事件在手机上没有触发，在工具有触发，但是在事件中执行wx.redirectTo没有反应，执行wx.switchTab可以跳转，会提示警告‘switchTab before pages are registered.’，而且跳转到首页并没有执行onload事件

onPageNotFound(res) {       console.log(res)       if (res.isEntryPage){           wx.redirectTo({               url: '/page/home/index/index',           })       }else{           let pages = getCurrentPages();           if (pages.length){               wx.showModal({                   content: '对不起，你访问的页面已消失',                   cancelText:'返回',                   confirmText:'去首页',                   success(res){                       if(res.confirm){                           wx.switchTab({                               url: '/page/home/index/index',                           })                       }else{                           wx.navigateBack()                       }                   }               })           }       }   }

还有一个问题是onPageNotFound事件触发是页面跳转之后还是跳转之前，来判断提示取消之后是否执行wx.navigateBack