Can you kindly create sample project reproducing the issue you are facing and share it us over Google-Drive or One Drive so that we can understand your scenario better and help you out?
—-
Manoj Mohan
Team CanvasJS
rangeChanging event is fired when the range of the chart is about to be changed i.e. just before rendering of the chart with updated viewport values. While rangeChanged event is fired after the chart is rendered with updated viewport values. With help of dynamicUpdate in StockChart, you can control when to fire rangeChanged and rangeChanging events. If dynamicUpdate is set to true, then range of chart will be updated at every movement of handle and hence rangeChanging and rangeChanged will be fired on updated viewport values. When dynamicUpdate is set to false, the range of the chart will be not updated at every movement of handle but rather will be updated when you release the handle. So rangeChanged and rangeChanging will be fired only on release of handle.
—-
Manoj Mohan
Team CanvasJS
Sorry for the inconvenience caused. One of our team representative will get back to you over email.
—-
Manoj Mohan
Team CanvasJS
You can update the dataPoints using set method like stockChart.charts[0].data[0].set("dataPoints", subsetDataPoints)or update the stockchart options like stockChart.options.charts[0].data[0].dataPoints = subsetDataPoints. Please take a look at this updated JSFiddle for sample code.

—-
Manoj Mohan
Team CanvasJS
rangeChanging and rangeChanged are two different type of event handler which are fired before and after range is changed respectively. rangeChanging can be used to change chart options without any need to call render method to update the options in rangeChanging event handler. But in case of rangeChanged event, you need to call the render method again in order to reflect the change in chart options in the rangeChanged event handler. Please take a look at this JSFiddle for an example demonstrating the sequence in which rangeChanging and rangeChanged event handler is fired.

Furthermore, the “rangeChanged” event.type would seem to be over firing. I would have expected the “rangeChanging” event to fire during “onmousemove” as the user is dragging the slider and then the “rangeChanged” event.type would fire “onmouseup” as the user releases the slider. This would allow us to avoid unnecessary updates as the user is selecting their date range or update immediately depending on which event.type is fired.
You can set dynamicUpdate property of navigator to false to fire rangeChanged or rangeChanging event on mouseup in order to stop unneccessary updates while changing the range on mousemove. Please take a look at this updated JSFiddle for an example on the same.
—–
Manoj Mohan
Team CanvasJS
Glad that you figured it out. You can use connectNullData to connect adjacent non-null data with a straight line.
—-
Manoj Mohan
Team CanvasJS
Please take a look at this documentation page for step by step instruction for rendering multiple chart in a single page.

If you are still facing the issue, kindly create a sample project reproducing the issue you are facing and share it with us over Google-Drive or OneDrive so that we can look into the code, run it locally at our end to understand the scenario better and help you out.
—-
Manoj Mohan
Team CanvasJS
You can create a custom DOM for tooltip and show it on click of the dataPoint as shown in the code snippet below.
function showToolTipOnClick(e) {
isDataPointClicked = true;
if(dataPointShown !== e.dataPoint) {
clicked = true;
dataPointShown = e.dataPoint;
} else {
clicked = !clicked;
}
if(customToolTipDOM === null) {
customToolTipDOM = document.createElement("div");
e.chart.container.appendChild(customToolTipDOM);
customToolTipDOM.style.display = "none";
customToolTipDOM.style.position = "absolute";
customToolTipDOM.style.background = "#fff";
customToolTipDOM.style.border = "1px solid #dedede";
customToolTipDOM.style.borderRadius = "4px";
customToolTipDOM.style.padding = "8px";
customToolTipDOM.style.top = "0px";
customToolTipDOM.style.left = "0px";
}
if(clicked) {
left = Math.round(e.chart.axisX[0].convertValueToPixel(e.dataPoint.x)) + 30;
customToolTipDOM.style.left = "0px";
customToolTipDOM.style.top = Math.round(e.chart.axisY[0].convertValueToPixel(e.dataPoint.y)) + "px";
customToolTipDOM.innerHTML = e.dataPoint.toolTipData;
customToolTipDOM.style.display = "block";
if(left + customToolTipDOM.offsetWidth + 30 > e.chart.container.offsetWidth) {
left = left - customToolTipDOM.offsetWidth - 30;
}
customToolTipDOM.style.left = left + "px";
} else {
customToolTipDOM.style.display = "none";
}
}
chart.container.addEventListener("click", function() {
if(!isDataPointClicked && customToolTipDOM) {
customToolTipDOM.style.display = "none";
clicked = false;
}
isDataPointClicked = false;
});
Also, check out this updated JSFiddle for showing toolTip on click of the dataPoint.

—-
Manoj Mohan
Team CanvasJS
You can convert your laptime format string to milliseconds and pass it as y-values in the dataSeries. For axis labels, you format the milliseconds passed to your desired format (minutes:seconds:milliseconds) using labelFormatter & contentFormatter for tooltip. Please find the code-snippet below.
var dps = [
{ x: 1, y: "1:57:420" },
{ x: 2, y: "1:57:340" },
{ x: 3, y: "1:56:587" },
{ x: 4, y: "1:56:225" },
{ x: 5, y: "2:0:110" },
{ x: 6, y: "2:2:102" }
]
dps.forEach(dp => {
var splitString = dp.y.split(":");
dp.y = parseInt(splitString[0]) * 60 * 1000 + parseInt(splitString[1]) * 1000 + parseInt(splitString[2]);
})
function formatMilliSeconds(val) {
var minutes = parseInt(val / (60 * 1000));
var seconds = parseInt(val % (60 * 1000) / 1000);
var ms = parseInt(val % (60 * 1000) % 1000);
return minutes + ":" + seconds + ":" + ms;
}
var chart = new CanvasJS.Chart("chartContainer", {
.
.
.
axisY: {
labelFormatter: function(e) {
return formatMilliSeconds(e.value)
}
},
toolTip: {
contentFormatter: function(e) {
toolTipContent = "";
e.entries.forEach( (entry) => {
toolTipContent += "x -> " + entry.dataPoint.x + "<br/>y -> " + formatMilliSeconds(entry.dataPoint.y) + "<br/>"
})
return toolTipContent;
}
},
.
.
.
});
Also, check out this JSFiddle for complete working code.

—-
Manoj Mohan
Team CanvasJS
We are looking into your query and get back to you at the earliest.
—-
Manoj Mohan
Team CanvasJS
Are you trying to show laptime in y-axis?
And also, can you kindly create sample project with your requirement and share it us over Google-Drive or One Drive so that we can understand your requirement better and help you out?
—-
Manoj Mohan
Team CanvasJS
You can use tooltip’s showAtX method along with click event handler of dataSeries to show tooltip on clicking datapoint. Please check out the code snippet below.
var clicked = false;
var chart = new CanvasJS.Chart("chartContainer",
{
title:{
text: "Show toolTip on click of DataPoint"
},
toolTip: {
updated: function(e) {
// hide tooltip if datapoint is not clicked
if(!clicked)
e.chart.toolTip.hide();
}
},
data: [
{
click: showToolTipOnClick,
mouseout: hideToolTip,
dataPoints: [
{ x: 1, y: 297571, label: "Venezuela"},
{ x: 2, y: 267017, label: "Saudi"},
{ x: 3, y: 175200, label: "Canada"},
{ x: 4, y: 154580, label: "Iran"},
{ x: 5, y: 116000, label: "Russia"},
{ x: 6, y: 97800, label: "UAE"},
{ x: 7, y: 20682, label: "US"},
{ x: 8, y: 20350, label: "China"}
]
}
]
});
chart.render();
function showToolTipOnClick(e) {
clicked = !clicked;
clicked ? e.chart.toolTip.showAtX(e.dataPoint.x) : e.chart.toolTip.hide();
}
function hideToolTip(e) {
clicked = false;
e.chart.toolTip.hide()
}
Also, please take a look at this JSFiddle for complete working code.

—-
Manoj Mohan
Team CanvasJS
The problem is this does not redraw these horizontal lines when I toggle to the next graph(new options are set). Additionally, if I change the size of the browser window, open the inspect tab, or just toggle the zoom button in the toolbar(to the traverse curve option) the horizontal lines we drew disappear. How can I fix this behavior?
You can modify the react chart component to accept a function to redraw the line as prop which will be called whenever the chart options is changed. Also, in order to redraw the lines on toggling the zoom button and on resizing the browser window, you need to add a click event listener to the zoom button and resize event listener on window. Please take a look below for the code snippet on the same.
.
.
.
componentDidMount() {
if(typeof this.chart !== "undefined") {
this.calculateValuesInPixel(this.chart);
this.drawHorizontalLines(this.chart);
this.chart.container.querySelector(".canvasjs-chart-toolbar button:first-child").addEventListener('click', this.redrawLines)
window.addEventListener('resize', this.redrawLines );
}
}
componentDidUnMount() {
window.removeEventListener('resize', this.redrawLines );
}
selectChange = (e) => {
this.setState({optionIndex: e.target.value})
}
onChartUpdate = () => {
this.calculateValuesInPixel(this.chart);
this.drawHorizontalLines(this.chart);
}
.
.
.
Please check out this Stackblitz project for an example on drawing lines on chart and rendering it based on chart options selected from dropdown.

2) Ideally we would like the annotations to be entirely handled by CanvasJS. If we move forward and make a purchase, would it be possible to add x axes start and end points for Y axes striplines to the library?
It is not possible to add notation as an inbuilt feature as of now. On purchasing the developer license, you get the access for source code which you can modify as per your requirement.
—-
Manoj Mohan
Team CanvasJS
@rck,
CanvasJS exportChart method is used to export the chart in the client-side. In order to save the image on server, you need to use PhantomJS’s page.render method which renders the page and save it as an image on server.
—-
Manoj Mohan
Team CanvasJS