Use a computed property for the chart data. And instead of calling this.renderChart on watch wrap it in a method and reuse that method on mounted and in watch.
Vue.component("line-chart", {
extends: VueChartJs.Line,
props: ["data", "options"],
mounted() {
this.renderLineChart();
},
computed: {
chartData: function() {
return this.data;
}
},
methods: {
renderLineChart: function() {
this.renderChart(
{
labels: [
"January",
"February",
"March",
"April",
"May",
"June",
"July"
],
datasets: [
{
label: "Data One",
backgroundColor: "#f87979",
data: this.chartData
}
]
},
{ responsive: true, maintainAspectRatio: false }
);
}
},
watch: {
data: function() {
this._chart.destroy();
//this.renderChart(this.data, this.options);
this.renderLineChart();
}
}
});
var vm = new Vue({
el: ".app",
data: {
message: "Hello World",
dataChart: [10, 39, 10, 40, 39, 0, 0],
test: [4, 4, 4, 4, 4, 4]
},
methods: {
changeData: function() {
this.dataChart = [6, 6, 3, 5, 5, 6];
}
}
});<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width">
<title>Vue.jS Chart</title>
</head>
<body>
<div class="app">
{{ dataChart }}
<button v-on:click="changeData">Change data</button>
<line-chart :data="dataChart" :options="{responsive: true, maintainAspectRatio: false}"></line-chart>
</div>
<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.2.6/vue.min.js"></script>
<script src="https://unpkg.com/vue-chartjs@2.5.7-rc3/dist/vue-chartjs.full.min.js"></script>
</body>
</html>You could also make the options a computed property, and if option not going to change much you can setup default props. https://v2.vuejs.org/v2/guide/components.html#Prop-Validation
Here is a working codepen https://codepen.io/azs06/pen/KmqyaN?editors=1010