How to register component in vue+ts correctly?

Question

I have this code:
App.vue

<template>
  <v-container>
    <div>
      <schedule-table
      v-if = "schedule.length > 0"
      :exercises="schedule[0].exercises"
      />
    </div>
  </v-container>
</template>
<script lang="ts">

import Vue from "vue";
import { Component } from "vue-property-decorator";
import ScheduleTable from '@/components/ScheduleTable.vue'

@Component({
  components: {
    ScheduleTable,
  }
})
</script>

ScheduleTable.vue

<template>
  <v-container>
    <schedule-week
    :exercises="exercises"
    />
  </v-container>
</template>
<script lang="ts">
import Vue from "vue";
import { Component, Prop } from "vue-property-decorator";
import { IExercise } from "@/interfaces"
import ScheduleWeek from '@/components/ScheduleWeek.vue'

@Component({
  name: 'ScheduleWeek',
  components: {
    ScheduleWeek,
  }
})

@Component
export default class ScheduleTable extends Vue {
  @Prop( {required: true, type: Array } ) readonly exercises!: IExercise;
}
</script>

ScheduleWeek.vue

<template>
  <v-container
  :ex="exercises"
  >
    here is tables (but this tables dosn't show and any other text dosn't show)
  </v-container>
</template>
<script lang="ts">
import Vue from "vue";
import { Component, Prop } from "vue-property-decorator";
import { IExercise } from "@/interfaces"


@Component
export default class ScheduleWeek extends Vue {
  @Prop( {required: true, type: Array } ) readonly exercises!: IExercise;
}
</script>

And have vue warn:

Unknown custom element: < schedule-week > - did you register the component correctly? For recursive components, make sure to provide the "name" option.

How to fix this problem? How to register component correctly?

Answer 1

There are multiple ways to declare a vue-component when you use typescript. The class-based SFC approach (the one you are using) needs to follow a slightly different syntax. You used the typescript decorator twice in your schedule-week component

App.vue

<v-container>
    <div>
      <schedule-table
      v-if = "schedule.length > 0"
      :exercises="schedule[0].exercises"
      />
    </div>
  </v-container>
</template>
<script lang="ts">

import { Component, Vue } from "vue-property-decorator"; // you can import vue here
import ScheduleTable from '@/components/ScheduleTable.vue'

@Component({
  components: {
    ScheduleTable,
  }
})
export default class App extends Vue {} // the @Component() decorator needs to be followed by the exported class

Correspondingly your other components:

ScheduleTable.vue

<template>
  <v-container>
    <schedule-week
    :exercises="exercises"
    />
  </v-container>
</template>
<script lang="ts">
import { Component, Vue, Prop } from "vue-property-decorator"; // see above
import { IExercise } from "@/interfaces"
import ScheduleWeek from '@/components/ScheduleWeek.vue'

@Component({
  name: 'ScheduleTable',
  components: {
    ScheduleWeek,
  }
}) // >>>don't use the decorator twice<<<
export default class ScheduleTable extends Vue {
  @Prop( {required: true, type: Array } ) readonly exercises!: IExercise;
}
</script>

ScheduleWeek.vue

<template>
  <v-container
  :ex="exercises"
  >
    here is tables (but this tables dosn't show and any other text dosn't show)
  </v-container>
</template>
<script lang="ts">
import { Component, Vue, Prop } from "vue-property-decorator"; // see above
import { IExercise } from "@/interfaces"


@Component
export default class ScheduleWeek extends Vue {
  @Prop( {required: true, type: Array } ) readonly exercises!: IExercise;
}
</script>

##EDIT:

From the officiel TypeScript Documentation:

With the introduction of Classes in TypeScript and ES6, there now exist certain scenarios that require additional features to support annotating or modifying classes and class members. Decorators provide a way to add both annotations and a meta-programming syntax for class declarations and members.

Decorators are basically TypeScript(JavaScript) functions which are used to add additional information to the following class (your component) or class members. This also means a decorator cannot stand alone. The @Component() decorator takes an Object as parameter which is 'as-is' translated into component-options.