I created a line chart, and added a button whose click method make the line thicker (lineWidth 7pt). However, each time I mouse over the line or the legend, the line restore to its original width (which I believe is 2 pt). So I added the following plot options to disable the "hover" function:

    line: {
        states: {
            hover: {
                enabled: false,
            }
        }
    }, 

But it only resolves the issue partially -- after I set lineWidth to 7 pt using the button, the line width will still be reset to its original 2 pt after I mouse over the legend or move mouse across the plotting area.

I have shared my example here. Can anyone help me figure out how to prevent resetting the line width after changing its width to 7 pt?

Thanks in advance!

Alex.

You can use

 series.update({
            lineWidth:10
        });

http://jsfiddle.net/QNPYP/2/

http://api.highcharts.com/highcharts#Series.update()