图例鼠标移动上去，如何给具体某一图例出现自定义提示 #4956

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plot.on('legend-item:mouseover', ev => { const target = ev.target; const delegateObject = target.get('delegateObject'); const item = delegateObject.item; // 图例选项 // 如何将获得图例item出现tooltip });

Checklist

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• npm test passes
• benchmarks are included
• commit message follows commit guidelines
• documents are updated

Description of change

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