tooltip not working on using scroller in vegaLite

Question

I am trying to add scroller in vegalite chart by just using vconcat composition, issue is that tooltip not visible/shown of vconcat[0] (main chart) but tooltip is completely visible in vconcat[1] (for scroller) ,why making tooltip true is not working in vconcat[0] (main chart) I want by making tooltip true in mark show tooltip on hover in chart without external defining toottip in encoding.

Editor link-https://vega.github.io/editor/#/url/vega-lite/N4IgJAzgxgFgpgWwIYgFwhgF0wBwqgegIDc4BzJAOjIEtMYBXAI0poHsDp5kTykBaADZ04JAKyUAVhDYA7EABoQAEySYUqUAwBOgtCrVJOOMQAZTlKBGIgAvkuJQ5UNWgDaoAO41l9NABYADlMlZG0AazRQTABPHDh9JiRtRRBMNjZBTBocNExtBjh7EDhZJ2UaWTIokAAPGoAzGjhBZX1VTASlWPj9ToQcNm0kPSVoEYTNFTZkSpqcZKQERIKIGDtipFqaCBrszEFJkA2lGMbm1v0cbRooLrS4o4BHBiRZfbUaUg37Lx8-VBBEIYOA0MhYNAANmBYUiUx6RySKW6GSyOTyBSKSgWwwQu1QHhAsiWiNW6zGLTgUEwe0e+kqnW0xBGqVK5UqZHxbjqIAAurZbLylGy2BUqjV6lMmi02ugOvcEX1EINhnpimcpRdZSBrrcFXT0C83h9st8lFsdntbuEAMJsBjvNAAZiUZBusoaIwgRQFgtsQA

I want by making tooltip true in mark show tooltip on hover in chart without external defining toottip in encoding.

Answer 1

Turn interactive to true.

{
  "$schema": "https://vega.github.io/schema/vega/v5.json",
  "background": "white",
  "padding": 5,
  "width": 480,
  "data": [
    {"name": "brush_store"},
    {
      "name": "source_0",
      "url": "data/sp500.csv",
      "format": {"type": "csv", "parse": {"date": "date"}, "delimiter": ","}
    },
    {
      "name": "data_0",
      "source": "source_0",
      "transform": [
        {
          "type": "stack",
          "groupby": ["date"],
          "field": "price",
          "sort": {"field": [], "order": []},
          "as": ["price_start", "price_end"],
          "offset": "zero"
        },
        {
          "type": "filter",
          "expr": "(isDate(datum[\"date\"]) || (isValid(datum[\"date\"]) && isFinite(+datum[\"date\"]))) && isValid(datum[\"price\"]) && isFinite(+datum[\"price\"])"
        }
      ]
    },
    {
      "name": "data_1",
      "source": "source_0",
      "transform": [
        {
          "type": "stack",
          "groupby": ["date"],
          "field": "price",
          "sort": {"field": [], "order": []},
          "as": ["price_start", "price_end"],
          "offset": "zero"
        },
        {
          "type": "filter",
          "expr": "(isDate(datum[\"date\"]) || (isValid(datum[\"date\"]) && isFinite(+datum[\"date\"]))) && isValid(datum[\"price\"]) && isFinite(+datum[\"price\"])"
        }
      ]
    }
  ],
  "signals": [
    {"name": "concat_0_height", "value": 200},
    {"name": "concat_1_height", "value": 60},
    {
      "name": "unit",
      "value": {},
      "on": [
        {"events": "pointermove", "update": "isTuple(group()) ? group() : unit"}
      ]
    },
    {
      "name": "brush",
      "update": "vlSelectionResolve(\"brush_store\", \"union\")"
    }
  ],
  "layout": {"padding": 20, "columns": 1, "bounds": "full", "align": "each"},
  "marks": [
    {
      "type": "group",
      "name": "concat_0_group",
      "style": "cell",
      "encode": {
        "update": {
          "width": {"signal": "width"},
          "height": {"signal": "concat_0_height"}
        }
      },
      "marks": [
        {
          "name": "concat_0_marks",
          "type": "rect",
          "clip": true,
          "style": ["bar"],
          "interactive": true,
          "from": {"data": "data_0"},
          "encode": {
            "update": {
              "tooltip": {
                "signal": "{\"date\": timeFormat(datum[\"date\"], '%b %d, %Y'), \"price\": format(datum[\"price\"], \"\")}"
              },
              "fill": {"value": "#4c78a8"},
              "ariaRoleDescription": {"value": "bar"},
              "description": {
                "signal": "\"date: \" + (timeFormat(datum[\"date\"], '%b %d, %Y')) + \"; price: \" + (format(datum[\"price\"], \"\"))"
              },
              "xc": {"scale": "concat_0_x", "field": "date"},
              "width": {"value": 5},
              "y": {"scale": "concat_0_y", "field": "price_end"},
              "y2": {"scale": "concat_0_y", "field": "price_start"}
            }
          }
        }
      ],
      "axes": [
        {
          "scale": "concat_0_x",
          "orient": "bottom",
          "gridScale": "concat_0_y",
          "grid": true,
          "tickCount": {"signal": "ceil(width/40)"},
          "domain": false,
          "labels": false,
          "aria": false,
          "maxExtent": 0,
          "minExtent": 0,
          "ticks": false,
          "zindex": 0
        },
        {
          "scale": "concat_0_y",
          "orient": "left",
          "gridScale": "concat_0_x",
          "grid": true,
          "tickCount": {"signal": "ceil(concat_0_height/40)"},
          "domain": false,
          "labels": false,
          "aria": false,
          "maxExtent": 0,
          "minExtent": 0,
          "ticks": false,
          "zindex": 0
        },
        {
          "scale": "concat_0_x",
          "orient": "bottom",
          "grid": false,
          "labelFlush": true,
          "labelOverlap": true,
          "tickCount": {"signal": "ceil(width/40)"},
          "zindex": 0
        },
        {
          "scale": "concat_0_y",
          "orient": "left",
          "grid": false,
          "title": "price",
          "labelOverlap": true,
          "tickCount": {"signal": "ceil(concat_0_height/40)"},
          "zindex": 0
        }
      ]
    },
    {
      "type": "group",
      "name": "concat_1_group",
      "style": "cell",
      "encode": {
        "update": {
          "width": {"signal": "width"},
          "height": {"signal": "concat_1_height"}
        }
      },
      "signals": [
        {
          "name": "brush_x",
          "value": [],
          "on": [
            {
              "events": {
                "source": "scope",
                "type": "pointerdown",
                "filter": [
                  "!event.item || event.item.mark.name !== \"brush_brush\""
                ]
              },
              "update": "[x(unit), x(unit)]"
            },
            {
              "events": {
                "source": "window",
                "type": "pointermove",
                "consume": true,
                "between": [
                  {
                    "source": "scope",
                    "type": "pointerdown",
                    "filter": [
                      "!event.item || event.item.mark.name !== \"brush_brush\""
                    ]
                  },
                  {"source": "window", "type": "pointerup"}
                ]
              },
              "update": "[brush_x[0], clamp(x(unit), 0, width)]"
            },
            {
              "events": {"signal": "brush_scale_trigger"},
              "update": "[scale(\"concat_1_x\", brush_date[0]), scale(\"concat_1_x\", brush_date[1])]"
            },
            {
              "events": [{"source": "view", "type": "dblclick"}],
              "update": "[0, 0]"
            },
            {
              "events": {"signal": "brush_translate_delta"},
              "update": "clampRange(panLinear(brush_translate_anchor.extent_x, brush_translate_delta.x / span(brush_translate_anchor.extent_x)), 0, width)"
            },
            {
              "events": {"signal": "brush_zoom_delta"},
              "update": "clampRange(zoomLinear(brush_x, brush_zoom_anchor.x, brush_zoom_delta), 0, width)"
            }
          ]
        },
        {
          "name": "brush_date",
          "on": [
            {
              "events": {"signal": "brush_x"},
              "update": "brush_x[0] === brush_x[1] ? null : invert(\"concat_1_x\", brush_x)"
            }
          ]
        },
        {
          "name": "brush_scale_trigger",
          "value": {},
          "on": [
            {
              "events": [{"scale": "concat_1_x"}],
              "update": "(!isArray(brush_date) || (+invert(\"concat_1_x\", brush_x)[0] === +brush_date[0] && +invert(\"concat_1_x\", brush_x)[1] === +brush_date[1])) ? brush_scale_trigger : {}"
            }
          ]
        },
        {
          "name": "brush_tuple",
          "on": [
            {
              "events": [{"signal": "brush_date"}],
              "update": "brush_date ? {unit: \"concat_1\", fields: brush_tuple_fields, values: [brush_date]} : null"
            }
          ]
        },
        {
          "name": "brush_tuple_fields",
          "value": [{"field": "date", "channel": "x", "type": "R"}]
        },
        {
          "name": "brush_translate_anchor",
          "value": {},
          "on": [
            {
              "events": [
                {
                  "source": "scope",
                  "type": "pointerdown",
                  "markname": "brush_brush"
                }
              ],
              "update": "{x: x(unit), y: y(unit), extent_x: slice(brush_x)}"
            }
          ]
        },
        {
          "name": "brush_translate_delta",
          "value": {},
          "on": [
            {
              "events": [
                {
                  "source": "window",
                  "type": "pointermove",
                  "consume": true,
                  "between": [
                    {
                      "source": "scope",
                      "type": "pointerdown",
                      "markname": "brush_brush"
                    },
                    {"source": "window", "type": "pointerup"}
                  ]
                }
              ],
              "update": "{x: brush_translate_anchor.x - x(unit), y: brush_translate_anchor.y - y(unit)}"
            }
          ]
        },
        {
          "name": "brush_zoom_anchor",
          "on": [
            {
              "events": [
                {
                  "source": "scope",
                  "type": "wheel",
                  "consume": true,
                  "markname": "brush_brush"
                }
              ],
              "update": "{x: x(unit), y: y(unit)}"
            }
          ]
        },
        {
          "name": "brush_zoom_delta",
          "on": [
            {
              "events": [
                {
                  "source": "scope",
                  "type": "wheel",
                  "consume": true,
                  "markname": "brush_brush"
                }
              ],
              "force": true,
              "update": "pow(1.001, event.deltaY * pow(16, event.deltaMode))"
            }
          ]
        },
        {
          "name": "brush_modify",
          "on": [
            {
              "events": {"signal": "brush_tuple"},
              "update": "modify(\"brush_store\", brush_tuple, true)"
            }
          ]
        }
      ],
      "marks": [
        {
          "name": "brush_brush_bg",
          "type": "rect",
          "clip": true,
          "encode": {
            "enter": {
              "fill": {"value": "#333"},
              "fillOpacity": {"value": 0.125}
            },
            "update": {
              "x": [
                {
                  "test": "data(\"brush_store\").length && data(\"brush_store\")[0].unit === \"concat_1\"",
                  "signal": "brush_x[0]"
                },
                {"value": 0}
              ],
              "y": [
                {
                  "test": "data(\"brush_store\").length && data(\"brush_store\")[0].unit === \"concat_1\"",
                  "value": 0
                },
                {"value": 0}
              ],
              "x2": [
                {
                  "test": "data(\"brush_store\").length && data(\"brush_store\")[0].unit === \"concat_1\"",
                  "signal": "brush_x[1]"
                },
                {"value": 0}
              ],
              "y2": [
                {
                  "test": "data(\"brush_store\").length && data(\"brush_store\")[0].unit === \"concat_1\"",
                  "field": {"group": "height"}
                },
                {"value": 0}
              ]
            }
          }
        },
        {
          "name": "concat_1_marks",
          "type": "rect",
          "style": ["bar"],
          "interactive": true,
          "from": {"data": "data_1"},
          "encode": {
            "update": {
              "tooltip": {
                "signal": "{\"date\": timeFormat(datum[\"date\"], '%b %d, %Y'), \"price\": format(datum[\"price\"], \"\")}"
              },
              "fill": {"value": "#4c78a8"},
              "ariaRoleDescription": {"value": "bar"},
              "description": {
                "signal": "\"date: \" + (timeFormat(datum[\"date\"], '%b %d, %Y')) + \"; price: \" + (format(datum[\"price\"], \"\"))"
              },
              "xc": {"scale": "concat_1_x", "field": "date"},
              "width": {"value": 5},
              "y": {"scale": "concat_1_y", "field": "price_end"},
              "y2": {"scale": "concat_1_y", "field": "price_start"}
            }
          }
        },
        {
          "name": "brush_brush",
          "type": "rect",
          "clip": true,
          "encode": {
            "enter": {"fill": {"value": "transparent"}},
            "update": {
              "x": [
                {
                  "test": "data(\"brush_store\").length && data(\"brush_store\")[0].unit === \"concat_1\"",
                  "signal": "brush_x[0]"
                },
                {"value": 0}
              ],
              "y": [
                {
                  "test": "data(\"brush_store\").length && data(\"brush_store\")[0].unit === \"concat_1\"",
                  "value": 0
                },
                {"value": 0}
              ],
              "x2": [
                {
                  "test": "data(\"brush_store\").length && data(\"brush_store\")[0].unit === \"concat_1\"",
                  "signal": "brush_x[1]"
                },
                {"value": 0}
              ],
              "y2": [
                {
                  "test": "data(\"brush_store\").length && data(\"brush_store\")[0].unit === \"concat_1\"",
                  "field": {"group": "height"}
                },
                {"value": 0}
              ],
              "stroke": [
                {"test": "brush_x[0] !== brush_x[1]", "value": "white"},
                {"value": null}
              ]
            }
          }
        }
      ],
      "axes": [
        {
          "scale": "concat_1_x",
          "orient": "bottom",
          "gridScale": "concat_1_y",
          "grid": true,
          "tickCount": {"signal": "ceil(width/40)"},
          "domain": false,
          "labels": false,
          "aria": false,
          "maxExtent": 0,
          "minExtent": 0,
          "ticks": false,
          "zindex": 0
        },
        {
          "scale": "concat_1_x",
          "orient": "bottom",
          "grid": false,
          "title": "date",
          "labelFlush": true,
          "labelOverlap": true,
          "tickCount": {"signal": "ceil(width/40)"},
          "zindex": 0
        },
        {
          "scale": "concat_1_y",
          "orient": "left",
          "grid": false,
          "title": "price",
          "tickCount": 3,
          "labelOverlap": true,
          "zindex": 0
        }
      ]
    }
  ],
  "scales": [
    {
      "name": "concat_0_x",
      "type": "time",
      "domain": {"data": "data_0", "field": "date"},
      "domainRaw": {"signal": "brush[\"date\"]"},
      "range": [0, {"signal": "width"}],
      "padding": 5
    },
    {
      "name": "concat_0_y",
      "type": "linear",
      "domain": {"data": "data_0", "fields": ["price_start", "price_end"]},
      "range": [{"signal": "concat_0_height"}, 0],
      "nice": true,
      "zero": true
    },
    {
      "name": "concat_1_x",
      "type": "time",
      "domain": {"data": "data_1", "field": "date"},
      "range": [0, {"signal": "width"}],
      "padding": 5
    },
    {
      "name": "concat_1_y",
      "type": "linear",
      "domain": {"data": "data_1", "fields": ["price_start", "price_end"]},
      "range": [{"signal": "concat_1_height"}, 0],
      "nice": true,
      "zero": true
    }
  ]
}