typescript使用mixins报错了

15:59:02.935 [tsl] ERROR at pages\index\index.vue:25
15:59:02.936 TS2339:Property 'checkIsLogin' does not exist on type 'CombinedVueInstance<Vue, { title: string; isInit: boolean; }, unknown, unknown, Readonly<Record<never, any>>>'.
15:59:02.938 [tsl] ERROR at pages\index\index.vue:36
15:59:02.940 TS2339:Property 'checkIsLogin' does not exist on type 'CombinedVueInstance<Vue, { title: string; isInit: boolean; }, unknown, unknown, Readonly<Record<never, any>>>'.