[Bug] keyTimeFormat of tooltip not work

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1,800 stars (1,800 stars)

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Avg merge 3d 12h (Avg merge 3d 12h)15 merged PRs in 30d (15 merged PRs in 30d)

Description

const spec = {
  "type": "line",
  "data": {
    "values": [
      {
        "time": "1744859339559",
        "value": 8
      },
      {
        "time": "1744859349559",
        "value": 9
      },
      {
        "time": "1744859359559",
        "value": 11
      },
      {
        "time": "1744859369559",
        "value": 14
      },
      {
        "time": "1744859379559",
        "value": 16
      }
    ]
  },
  "xField": "time",
  "yField": "value",
  "axes": [
    {
      "orient": "bottom",
      "_alias_name": "xAxis",
      "label": {
        "formatMethod": function (label) { return new Date(Number(label)).toLocaleString(); }
      }
    }
  ],
  tooltip: {
    dimension: {
      content: [{
        keyTimeFormat: 'yyyy-MM-dd HH:mm:ss'
      }]
    }
  }
};

- OS:
- Browser:
- Framework:

Contributor guide

Research direction

Investigate the tooltip component code in VChart, specifically the keyTimeFormat property handling. Trace how the tooltip content is rendered and where keyTimeFormat is applied. Check if the format is being ignored or overwritten.

Tech stack

typescriptjavascript

Domain

frontenddata visualization

Issue type

Bug

DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.

2

Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.

1-3 hours

Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.

Active

ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.

Mostly clear

Prerequisites

TypeScriptGit

Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.

70