Getting index of a data in an array in VUE js

Question

I want to change the status of Tasks when a particular method is called. But The problem is I cannot get the index of the particular item of the array to change its status. This is my HTML:

<div class="main" id="my-vue-app">
    <ul>
        <li v-for="task in completeTask">
            {{ task.description }} <button @click="markIncomplete">Mark as Incomplete</button>
        </li>

    </ul>
    <ul>
        <li v-for="task in incompleteTask">
            {{ task.description }} <button @click="markComplete">Mark as Complete</button>

        </li>
    </ul>
</div>

And this is my Vue:

<script>
    new Vue(
        {
            el: '#my-vue-app',
            data:
            {
                tasks: [
                {description:'go to market', status: true},
                {description:'buy book', status: true}, 
                {description:'eat biriani', status: true}, 
                {description:'walk half kilo', status: false}, 
                {description:'eat icecream', status: false}, 
                {description:'return to home', status: false}
                ]
            },
            computed: 
            {
                incompleteTask()
                {
                    return this.tasks.filter(task => ! task.status);
                },
                completeTask()
                {
                    return this.tasks.filter(task => task.status);
                }
            },
            methods: 
            {
                markComplete()
                {
                    return this.task.status = true;

                },
                markIncomplete()
                {
                    return this.task.status = false;
                }
            }
        }
    )
</script>

I need make use of markComplete() and markIncomplete() but the problem is I couldn't find the way to get the index of current element to change its status.

Answer 1

You could get the index by declaring a second argument at the v-for:

<li v-for="(task, index) in incompleteTask">
    {{ task.description }} <button @click="markComplete(index)">Mark as Complete</button>
</li>

    methods: 
    {
        markComplete(index)
        {
            return this.tasks[index].status = true;

        },

But a, maybe simpler, alternative is to simply **pass the `task` as argument**:

<li v-for="task in incompleteTask">
    {{ task.description }} <button @click="markComplete(task)">Mark as Complete</button>
</li>

    methods: 
    {
        markComplete(task)
        {
            return task.status = true;

        },