如何通过原子设计模式中的发射，从vuetify选择中得到改变的值？

Question

我试图通过使用vuetify v-select获得更改后的$emit值，但它不起作用。我通过应用原子设计模式(原子(子组件而不是与存储连接)、生物体(父组件)和vuex存储来划分组件。我认为$emit数据是可以的，但是在这个过程之后，任何东西都不能工作。

这是一个使用vue, vuex, vuetify,原子设计连接到API服务器的管理页面的新应用程序。

组件

子组件- in原子文件夹

<template>
  <v-select
    :items="list"
    :label="label"
    v-model="selected"
    item-value="id"
    item-text="name"
    return-object
    @change="changeSelected"
  ></v-select>
</template>

<script>
export default {
  props: ["list", "label", "defaultSelected"],
  data() {
    return {
      selected: this.defaultSelected
    };
  },
  methods: {
    changeSelected(newValue) {
      console.log(newValue);    // display changed new data
      this.$emit("changeSelected", newValue);
    }
  }
};
</script>

父组件- in有机物文件夹

<template>
  <v-select-child
    :select-label="label"
    :select-list="list"
    :default-selected="selected"
    @change-selected="changeSelected"    // problem issue?
  >
  </v-select-child>
</template>
<script>
import { mapState } from "vuex";
export default {
  data() {
    ...
  },
  computed: {
    ...mapState({
      list: state => state.list
    })
  },
  methods: {
    changeSelected() {
      console.log("changeSelected");    // doesn't work
      this.$store.dispatch("setSelected", { payload: this.selected });
    }
  }
};
</script>

vuex商店

index.js

export default new Vuex.Store({
  modules: {
    xxx
  },
  state: {
    list: [
      {
        name: "aaaaa",
        id: "001"
      },
      {
        name: "bbbbb",
        id: "002"
      }
    ]
  },
  getters: {},
  mutations: {},
  actions: {}
});

xxx.js

export default {
    selected: { id: "001" }
  },

  getters: {
    //
  },

  mutations: {
    updateSelected(state, payload) {
      console.log("payload");    // doesn't work
      console.log(payload);
      state.selected = payload;
      console.log(state.selected);
    }
  },

  actions: {
    setSelected({ commit }, payload) {
      console.log("Action");    // doesn't work
      commit("updateSelected", payload);
    }
  }
};

它不会在changeSelected函数之后打印任何控制台日志。

Answer 1

在文档中

与组件和道具不同，事件名称不提供任何自动案例转换。相反，发出的事件的名称必须与用于侦听该事件的名称完全匹配。

这意味着如果您发出像$emit('changeSelected')这样的事件，那么您需要使用@changeSelected。@change-selected将无法工作。

 <v-select-child
    :select-label="label"
    :select-list="list"
    :default-selected="selected"
    @changeSelected="changeSelected" 
  >
</v-select-child>

Answer 2

我找到了以下解决方案：

子组件

<template>
  <v-select
    :label="label"
    :items="list"
    v-model="selected"
    item-value="id"
    item-text="name"
    return-object
  ></v-select>
</template>

<script>
export default {
  props: ["list", "label", "defaultSelected"],
  computed: {
    selected: {
      get() {
        return this.defaultSelected;
      },
      set(newVal) {
        if (this.selected !== newVal) {
          this.$emit("changeSelected", newVal);
        }
      }
    }
  }
};
</script>

父组件

<template>
  <v-select-child
   :label="label"
   :list="list"
   :defaultSelected="selected"
   @changeSelected="changeSelected"  // fix the property using camelCase
  ></v-select-child>
</template>

<script>
import { mapState } from "vuex";
export default {
  data() {
    ...
  },
  computed: {
    ...mapState({
      list: state => state.list
    })
  },
  methods: {
    changeSelected(val) {   // val: changed object value
      this.$store.dispatch("setSelected", { id:val.id });
    }
  }
};
</script>

Answer 3

你也可以用手表；

  <v-select
    :label="label"
    :items="list"
    v-model="selected"
    item-value="id"
    item-text="name"
  ></v-select>
</template>

...
watch:{
   selected(){
      this.$emit('changeValue', this.selected.id');
   }
}
...

来自父母；

<child @changeValue="id = $event" .. />