I got the following two components:
Parent:
<template>
<v-container>
<v-row class="text-center">
<v-col cols="12" class="parent">
<p>Ich bin der Parent component</p>
<button @click="changeDetail" :name.sync="name">Change Details</button>
<Child v-bind:name="name"></Child>
</v-col>
</v-row>
</v-container>
</template>
<script>
import Child from "./Child";
export default {
name: "Parent",
data: () => ({
name: "test"
}),
methods: {
changeDetail() {
this.name = "Updated from Parent";
}
},
components: {
Child
}
};
</script>
Child:
<template>
<v-container>
<v-row class="text-center">
<v-col cols="12">
<p>My name is: {{ name}}</p>
<button @click="resetname">Reset the name</button>
</v-col>
</v-row>
</v-container>
</template>
<script>
export default {
// props: ["name"],
props: {
name: {
type: String,
required: true
}
},
data: () => ({
newname: "Updated from Child"
}),
methods: {
resetname() {
this.$emit("update:name", this.newname);
}
}
};
</script>
As far as I read here: https://v2.vuejs.org/v2/guide/components-custom-events.html#sync-Modifier, I should use update and sync to pass props from the child back to the parent. However it does not work. I don´t understand what´s wrong here. What am I missing?
It is usually best to not bind your template to the prop but a computed property instead to ensure the data is accessed and modified externally. It will also simplify your code a bit so that you don't have to trigger updates.
<template>
<v-container>
<v-row class="text-center">
<v-col cols="12" class="parent">
<p>Ich bin der Parent component</p>
<button @click="changeDetail">Change Details</button>
<Child v-bind:name.sync="name"></Child>
</v-col>
</v-row>
</v-container>
</template>
<script>
import Child from "./Child";
export default {
name: "Parent",
data: () => ({
name: "test"
}),
methods: {
changeDetail() {
this.name = "Updated from Parent";
}
},
components: {
Child
}
};
</script>
<template>
<v-container>
<v-row class="text-center">
<v-col cols="12">
<p>My name is: {{ currentName }}</p>
<button @click="resetname">Reset the name</button>
</v-col>
</v-row>
</v-container>
</template>
<script>
export default {
// props: ["name"],
props: {
name: {
type: String,
required: true
}
},
data: () => ({
//Be careful with fat arrow functions for data
//Because the value of *this* isn't the component,
//but rather the parent scope.
}),
computed: {
currentName: {
get() { return this.name },
set(value) { this.$emit("update:name", value); }
}
},
methods: {
resetname() {
this.currentName = "updated from child";
}
}
};
</script>