Question

我尝试过的事情： 我包括一个range滑块。此范围滑块旨在更改数据过滤的方式（请参见transform）。（几乎与本示例https://vega.github.io/vega/examples/population-pyramid/类似）

问题：
当我更改滑块在图形上的位置时，图形的输入没有变化。

问题： 如何更改代码，以便通过用户与范围滑块的交互来更改我的输入参数？

{
      "$schema": "https://vega.github.io/schema/vega/v5.json",
      "width": 400,
      "height": 200,
      "padding": 20,
    
    "signals": [
        {
          "name": "tooltip",
          "value": {},
          "on": [
            {"events": "rect:mouseover", "update": "datum"},
            {"events": "rect:mouseout",  "update": "{}"}
          ]
        },
        {
          "name": "Y_Value",
          "bind":{"input": "range", "min": 0, "max": 100, "step": 1},
          "value": 100
        }
      ],
    
      "data": [
        {
          "name": "table",
          "values": [
            {"category": "A", "amount": 28},
            {"category": "B", "amount": 55},
            {"category": "C", "amount": 43},
            {"category": "D", "amount": 91},
            {"category": "E", "amount": 81},
            {"category": "F", "amount": 53},
            {"category": "G", "amount": 19},
            {"category": "H", "amount": 87}
          ]
        },
        {
          "name": "range",
          "source": "table",
          "transform": [
            {"type": "filter", "expr": "datum.amount <= Y_Value"}
          ]
        }
      ],
    
      
    
      "scales": [
        {
          "name": "xscale",
          "type": "band",
          "domain": {"data": "table", "field": "category"},
          "range": "width",
          "padding": 0.05,
          "round": true
        },
        {
          "name": "yscale",
          "domain": {"data": "table", "field": "amount"},
          "nice": true,
          "range": "height"
        }
      ],
    
      "axes": [
        { 
          "orient": "bottom",
          "scale": "xscale",
          "encode": {
            "labels": {
              "interactive": true,
              "update": {
                "tooltip": {"signal": "datum.label"}
              }
            }
          }
        },
        { "orient": "left", "scale": "yscale" }
      ],
    
      "marks": [
        {
          "type": "rect",
          "from": {"data":"table"},
          "encode": {
            "enter": {
              "x": {"scale": "xscale", "field": "category"},
              "width": {"scale": "xscale", "band": 1},
              "y": {"scale": "yscale", "field": "amount"},
              "y2": {"scale": "yscale", "value": 0}
              
            },
            "update": {
              "fill": {"value": "steelblue"}
    
            },
            "hover": {
              "fill": {"value": "red"}
            }
          }
        },
        {
          "type": "text",
          "encode": {
            "enter": {
              "align": {"value": "center"},
              "baseline": {"value": "bottom"},
              "fill": {"value": "#333"}
            },
            "update": {
              "x": {"scale": "xscale", "signal": "tooltip.category", "band": 0.5},
              "y": {"scale": "yscale", "signal": "tooltip.amount", "offset": -2},
              "text": {"signal": "tooltip.amount"},
              "fillOpacity": [
                {"test": "datum === tooltip", "value": 0},
                {"value": 1}
              ]
            }
          }
        }
      ]
    }

Answer 1

一段时间后，我想到了这一点：

{
      "$schema": "https://vega.github.io/schema/vega/v5.json",
      "width": 400,
      "height": 200,
      "padding": 20,
      "title": {"text":"A title", "anchor":"middle"},
    
    "signals": [
        {
          "name": "tooltip",
          "value": {},
          "on": [
            {"events": "rect:mouseover", "update": "datum"},
            {"events": "rect:mouseout",  "update": "{}"}
          ]
        },
        {
          "name": "Threshold",
          "bind":{"input": "range", "min": 0, "max": 100, "step": 1},
          "value": 0
        }
      ],
    
      "data": [
        {
          "name": "table",
          "values": [
            {"category": "Mon", "amount": 28},
            {"category": "Tue", "amount": 55},
            {"category": "wed", "amount": 43},
            {"category": "Thu", "amount": 91},
            {"category": "Fri", "amount": 81},
            {"category": "Sat", "amount": 53},
            {"category": "Sun", "amount": 19}   
          ]
        },
        {
          "name": "range",
          "source": "table",
          "transform": [
            {"type": "filter", "expr": "datum.amount >= Threshold"}
          ]
        }
      ],
    
      "scales": [
        {
          "name": "xscale",
          "type": "band",
          "domain": {"data": "table", "field": "category"},
          "range": "width",
          "padding": 0.05,
          "round": true
          
        },
        {
          "name": "yscale",
          "domain": {"data": "table", "field": "amount"},
          "nice": true,
          "range": "height"
        }
      ],
    
      "axes": [
        { 
          "orient": "bottom",
          "scale": "xscale",
          "encode": {
            "labels": {
              "interactive": true,
              "update": {
                "tooltip": {"signal": "datum.label"}
              }
            }
          }
        },
        { "orient": "left", "scale": "yscale", "title": "Y Title" }
      ],
    
      "marks": [
        {
          "type": "rect",
          "from": {"data":"range"},
          "encode": {
            "enter": {
              "x": {"scale": "xscale", "field": "category"},
              "width": {"scale": "xscale", "band": 1},
              "y": {"scale": "yscale", "field": "amount"},
              "y2": {"scale": "yscale", "value": 0}
            },
            "update": {
              "fill": {"value": "steelblue"}   
            },
            "hover": {
              "fill": {"value": "red"}
            }
          }
        },
        {
          "type": "text",
          "encode": {
            "enter": {
              "align": {"value": "center"},
              "baseline": {"value": "bottom"},
              "fill": {"value": "#333"}
            },
            "update": {
              "x": {"scale": "xscale", "signal": "tooltip.category", "band": 0.5},
              "y": {"scale": "yscale", "signal": "tooltip.amount", "offset": -2},
              "text": {"signal": "tooltip.amount"},
              "fillOpacity": [
                {"test": "datum === tooltip", "value": 0},
                {"value": 1}
              ],
              "align": {"value": "center"},
              "baseline": {"value": "bottom"},
              "fill": {"value": "#333"}
            }
          }
        }
      ]
    }

如何包括范围滑块以转换Vega中的数据？

1 个答案: