Добавление следующего должно скрыть легенду (я надеюсь, под цветовой рамкой заголовка вы подразумеваете легенду):
legend:
{
display: false
}
var canvas = document.getElementById('myChart');
var data = {
labels: ["January", "February", "March", "April", "May", "June", "July"],
datasets: [{
label: "My First dataset",
fill: false,
lineTension: 0.1,
backgroundColor: "rgba(75,192,192,0.4)",
borderColor: "rgba(75,192,192,1)",
borderCapStyle: 'butt',
borderDash: [],
borderDashOffset: 0.0,
borderJoinStyle: 'miter',
pointBorderColor: "rgba(75,192,192,1)",
pointBackgroundColor: "#fff",
pointBorderWidth: 1,
pointHoverRadius: 5,
pointHoverBackgroundColor: "rgba(75,192,192,1)",
pointHoverBorderColor: "rgba(220,220,220,1)",
pointHoverBorderWidth: 2,
pointRadius: 5,
pointHitRadius: 10,
data: [65, 59, 80, 0, 56, 55, 40],
}]
};
function adddata() {
myLineChart.data.datasets[0].data[7] = 60;
myLineChart.data.labels[7] = "Newly Added";
myLineChart.update();
}
var option = {
showLines: true,
legend: {
display: false
}
};
var myLineChart = Chart.Line(canvas, {
data: data,
options: option
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.1.3/Chart.min.js"></script>
<canvas id="myChart" width="400" height="250"></canvas>
<input type="button" value="Add Data" onclick="adddata()">