Chartjs-Enter an array of datasets into the dataset field of ChartJs

Your 2nd approach will work just fine if you change your definition of datData from an object to an array:

var datData = [ ydata, xdata ];

myChart[0] = new Chart(ctx, {
type: barbarblackbar,
data: {
    labels: ["Red", "Blue", "Yellow", "Green", "Purple", "Orange"],
    datasets: datData
    },
options: {
    scales: {
        yAxes: [{
            ticks: {
                beginAtZero:true
            }
        }]
    }
}
});