Axis-triggered tooltip failed to display some series if x axis values are not 100% equal!

[buhichan]

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Issue Details

Axis-triggered tooltip failed to display some series if x axis values are not 100% equal!

Expected Behavior

Axis-triggered should always show the nearest data index of all series, like this:

series1: 5
series2: 5

Current Behavior

It always shows one of the series, but never both.

Online Example

http://jsfiddle.net/sh1acjqu/3/

This is my chart options:

{
            title: {
                text: 'ECharts 入门示例'
            },
            tooltip: {
                trigger: "axis"
            },
            legend: {
                data:['销量']
            },
            xAxis: {
                type: "time"
            },
            yAxis: {},
            series: [{
                name: 'series1',
                type: 'line',
                data: [[1544770701,5], [1544770703,20], [1544770805,36]]
            },{
                name: 'series2',
                type: 'line',
                data: [[1544770702,5], [1544770704,20], [1544770806,36]]
            }]
        }

The stated problem is caused by these lines: lib/component/axisPointer/axisTrigger.js#198-203, I don't know the purpose of these codes, but when i comment out line 198~203, the resulted behavior is what i want.

If you guys think this is a wanted behavior, then i request an option to do this.

 // if (dist < minDist || diff >= 0 && minDiff < 0) {
      //   minDist = dist;
      //   minDiff = diff;
      //   snapToValue = seriesNestestValue;
      //   payloadBatch.length = 0;
      // }

Topics

• Legend
• Tooltip
• Event
• Performance
• SVG
• Map
• ECharts GL
• Third-party libraries, e.g.: Vue.js, React

Anything Else We Need to Know

Environment

• ECharts version；ECharts 版本: 4.2.0-rc.2 / 3.7.2 (it happens in both version, you can try in js fiddle)

• It happens only on certain browsers or operating systems. 对于特定浏览器或操作系统才会出现的问题，请提供相应环境信息：{BROWSER_VERSION_OR_OS_INFORMATION_HERE}

[Ovilia]

Because the x value of the two series are not the same. The first one is 1544770701 and the second one is 1544770702. But I think this should be improved so that all series are shown in tooltip when trigger is set to be axis.

[100pah]

As @Ovilia mentioned, I think if you intent to display both series in a tooltip, the x value should be the same.

If we make all of the series displayed in tooltip mandatorily in this case,
when a axisPointer is on a X value and some series do not have Y value corresponding to that x value,
which data item should be selected to show on tooltip?
I think it is not reasonable enough to choose a closest item to show on tooltip, because it may miss leading the readers.

[buhichan]

I don't see it's a misleading.
The difference is only 1 second, it is ignorable.
It's very common when you have multiple sourced time series data and their sampling rate are not synchronized.
If I don't have the option to do this (show the closest point), I am forced to modify the x value so that they are at the same x, but that would be misleading the viewers.

[IkerZamora]

Any update on this?

[Ovilia]

I think it's reasonable to display the two series if x axis has snap setting to be true.
Let's see what we can do after we fix #7651.

[Wintermute79]

Maybe same as #15488 ?