Section 1.1: Implementing Custom Decorators

We can enhance our Vue class-based components by introducing custom decorators. For example, consider the following implementation:

<template>

<div>

<button @click="increment(2)">increment</button>

<p>{{ count }}</p>

</div>

</template>

<script>

import Vue from "vue";

import Component, { createDecorator } from "vue-class-component";

const Log = createDecorator((options, key) => {

const originalMethod = options.methods[key];

options.methods[key] = function wrapperMethod(...args) {

console.log(Invoked: ${key}(, ...args, ")");

originalMethod.apply(this, args);

};

});

@Component

export default class HelloWorld extends Vue {

count = 0;

@Log

increment(val) {

this.count += val;

}

}

</script>

In this example, we create a Log decorator using the createDecorator method. The decorator takes a callback that receives the options and key parameters, where options contains component properties, and key is the method's name. We can then redefine the method by assigning a new function that wraps the original, allowing us to execute additional logic before calling it.

Section 1.2: Creating a Superclass Component

One of the advantages of class-based components is the ability to define a superclass component that encapsulates common properties we want to share among other components. Here’s how we can achieve this:

<template>

<div>

<p>{{ superValue }}</p>

</div>

</template>

<script>

import Vue from "vue";

import Component from "vue-class-component";

@Component

class Super extends Vue {

superValue = "Hello";

}

@Component

export default class HelloWorld extends Super {}

</script>

In this snippet, the Super component defines a property named superValue. The HelloWorld component inherits this property, allowing us to use it seamlessly within its template.

Furthermore, we can access inherited properties within the child component's lifecycle hooks:

<template>

<div>

<p>{{ superValue }}</p>

</div>

</template>

<script>

import Vue from "vue";

import Component from "vue-class-component";

@Component

class Super extends Vue {

superValue = "Hello";

}

@Component

export default class HelloWorld extends Super {

created() {

console.log(this.superValue);

}

}

</script>

In this example, we utilize the created lifecycle hook to log the inherited superValue, which should display 'Hello' in the console.