[错误] 抛出了 TypeError: 不能设置 undefined 的属性 (设置 'dataIndex')

*util.GraphData {Nodes: []GitHub.com/go-echarts/go-echarts/v2/opts.GraphNode len: 2, cap: 2, opts.GraphNode {Name: "test", X: 0, Y: 0, Value: 0, Fixed: *bool nil, Category: interface {}(string) "User", Symbol: "path://M399 384.2C376.9 345.8 335.4 320 288 320l-64 0c-47.4 0-88.9 25.8-111 64.2c35.2 39.2 86.2 63.8 143 63.8s107.8-24.7 143-63.8zM0 256a256 256 0 1 1 512 0A256 256 0 1 1 0 256zm256 16a72 72 0 1 0 0-144 72 72 0 1 0 0 144z", SymbolSize: interface {}(int) 40, ItemStyle: *GitHub.com/go-echarts/go-echarts/v2/opts.ItemStyle {Color: "#cddffa", Color0: "", BorderColor: "#f70200", BorderColor0: "", BorderColorSaturation: 0, BorderWidth: 1, GapWidth: 0, Opacity: 0, ShadowBlur: 5, ShadowColor: "rgba(0, 0, 0, 0.3)", ShadowOffsetX: 0, ShadowOffsetY: 0 }, opts.GraphNode {Name: "test", X: 0, Y: 0, Value: 0, Fixed: *bool nil, Category: interface {}(string) "Device", Symbol: "path://M256 512A256 256 0 1 0 256 0a256 256 0 1 0 0 512zM184 128l72 0c70.7 0 128 57.3 128 128s-57.3 128-128 128l-72 0c-13.3 0-24-10.7-24-24l0-208c0-13.3 10.7-24 24-24zm72 208c44.2 0 80-35.8 80-80s-35.8-80-80-80l-48 0 0 160 48 0z", SymbolSize: interface {}(int) 40, ItemStyle: *GitHub.com/go-echarts/go-echarts/v2/opts.ItemStyle {Color: "#CEF1EE", Color0: "", BorderColor: "#000000", BorderColor0: "", BorderColorSaturation: 0, BorderWidth: 1, GapWidth: 0, Opacity: 0, ShadowBlur: 5, ShadowColor: "rgba(0, 0, 0, 0.3)", ShadowOffsetX: 0, ShadowOffsetY: 0 }, ], opts.GraphLink {Source: interface {}(string) "test", Target: interface {}(string) "test", Value: 0, Label: *GitHub.com/go-echarts/go-echarts/v2/opts.EdgeLabel nil, LineStyle: *GitHub.com/go-echarts/go-echarts/v2/opts.LineStyle nil }, Categories: []*GitHub.com/go-echarts/go-echarts/v2/opts.GraphCategory len: 2, cap: 2, [*opts.GraphCategory {Name: "User", ItemStyle: *GitHub.com/go-echarts/go-echarts/v2/opts.ItemStyle {Color: "#cddffa", Color0: "", BorderColor: "", BorderColor0: "", BorderColorSaturation: 0, BorderWidth: 0, GapWidth: 0, Opacity: 0, …