Powerbi Report CLI

Conditional Formatting Patterns - Part 7

Contents

• Type 6: Field-Driven Color

  • Contract

  • Aggregation Function values

  • Selector

  • Applies to tables and matrices

  • Chart field-value color

• Type 7: Image Field Values

• Totals, subtotals, and the matrix total slot

• Column width — not conditionally formattable

• Chart color inheritance

  • Line, marker, legend, and series-label consistency

  • Category consistency across visuals

  • Line segment limitation

Continuation of conditional-formatting.md. Open this file directly from the skill reference index.

Type 6: Field-Driven Color

Colors a property using hex values stored in a data column. There is no special fieldValue property — this is a pattern of placing an Aggregation expression (referencing a color column) inside any standard color property slot (backColor, fontColor, foreColor, etc.).

Contract

{
  "properties": {
    "backColor": {
      "solid": {
        "color": {
          "expr": {
            "Aggregation": {
              "Expression": {
                "Column": {
                  "Expression": { "SourceRef": { "Entity": "Colors" } },
                  "Property": "Color"
                }
              },
              "Function": 3
            }
          }
        }
      }
    }
  },
  "selector": {
    "data": [{ "dataViewWildcard": { "matchingOption": 1 } }],
    "metadata": "Sum(OrderBreakdown.Sales)"
  }
}

Aggregation Function values

A color source column is wrapped in Aggregation with Min (3) or Max (4) — a text/color column has no numeric Sum/Average:

See Aggregation: columns vs. measures for the full Function enum and the measure-vs-column rule (a color-returning measure is referenced directly, with no Aggregation wrapper).

Selector

The metadata queryRef targets the column being colored (the measure or column whose cells receive the color), not the color source column.

Applies to tables and matrices

Works with backColor and fontColor. The color source column must contain valid color strings such as #FF6B35 — see Color value results (hex) for the accepted forms and the #RRGGBBAA caveat.

Chart field-value color

For charts, place a color-returning Measure or aggregated text Column expression in the supported chart color property. Choose the instance, category-role, or series-role selector that matches what the color repeats over; do not default every chart to one wildcard shape.

For a single-series non-combo line chart whose markers should vary by category, use this pattern and do not also set lineStyles.markerColor:

"dataPoint": [
  {
    "properties": {
      "fill": {
        "solid": {
          "color": {
            "expr": {
              "Measure": {
                "Expression": {
                  "SourceRef": { "Entity": "Sales" }
                },
                "Property": "Marker Color"
              }
            }
          }
        }
      }
    },
    "selector": {
      "data": [{ "roles": ["Category"] }]
    }
  }
]

When only markers should vary, add a static lineStyles.strokeColor. When segments and markers should match, apply the same conditional source to lineStyles.strokeColor and dataPoint.fill.

The measure must return a supported color value: hex, CSS color name, RGB/RGBA, HSL/HSLA, or a report-theme color name. Prefer a text-typed DAX measure. Calculation groups or mixed return types can make the measure variant typed and prevent field-value formatting from rendering.

For a color column, use an Aggregation expression with Function: 3 (Min) or Function: 4 (Max), matching the table/matrix pattern. Replace dataPoint.fill with another supported direct target from the chart capability matrix as needed.

Type 7: Image Field Values

Renders images inside table/matrix cells from a field of image URLs — the "Field value" style of conditional formatting (the output is driven by the data, like Type 6: Field-Driven Color). Unlike color/icon CF, there is no objects rule to author: image rendering is enabled by the field's Data Category. Any field whose Data Category is "Image URL" (TMDL dataCategory: ImageUrl) is rendered as an <img> in every data cell. Two supporting objects refine the result — grid (size) and accessibility.altTextColumns (alt text).

For standalone image visuals (an image on the canvas, not a cell) see image.md (see image.md).

Prerequisite — the field must be Image URL data-category. Inspect the TMDL first:

• Field has dataCategory: ImageUrl → place it in the visual; cells render as images automatically.

• Field lacks the category → cells render the raw URL text. Warn the user; offer to use an ImageUrl field or set the category on a column/measure holding valid image URLs.

• URLs must be valid, publicly reachable image URLs (HTTPS preferred). Invalid URLs render blank / broken.

Column vs measure placement:

• In a table (tableEx), an ImageUrl column goes in Values. Its grand-total cell is blank (no image) — a column has no value at the total grain. The word "Total" appears only in the visual's first / left-most (row-label) column, not in the image column itself.

• In a matrix (pivotTable), Values is a measure-only role: a raw column there fails validation (PBIR_ROLE_KIND_MISMATCH, "use Measure or Aggregation"). To show a column's images in matrix Values, wrap it in an Aggregation (e.g. Function: 3 = Min) or expose it as a measure; the raw column may otherwise be placed in matrix Rows / Columns (grouping roles).

• An ImageUrl measure is a value, not a grouping field — it must go in Values only. Placing a measure in Rows / Columns fails validation (PBIR_ROLE_KIND_MISMATCH, grouping-only role).

• Total-cell rule: anything that returns a URL in every context — a measure, or an Aggregation-wrapped column in matrix Values — renders the image in its total cell. A plain column (table Values, or matrix Rows / Columns) renders no image at the total: its own total cell is blank, and the word "Total" shows only in the visual's first / row-label column, because a column has no value at the total grain.

Image size — grid.imageHeight / grid.imageWidth (shared by all image columns in the visual):

"grid": [{
  "properties": {
    "imageHeight": { "expr": { "Literal": { "Value": "75D" } } },
    "imageWidth": { "expr": { "Literal": { "Value": "120D" } } }
  }
}]

Alt text — accessibility.altTextColumns. Bind a text field or measure per image column (same field-value shape as Type 6: Field-Driven Color), metadata = the image field's projection queryRef, matchingOption: 0 (InstancesAndTotals). The queryRef matches how the image is projected: a plain column → Table.Column; an Aggregation-wrapped column in matrix Values → Min(Table.Column); a measure → Table.Measure. Alt text works for image fields bound to Rows / Columns / Values:

{
  "properties": {
    "altTextColumns": {
      "expr": {
        "Aggregation": {
          "Expression": { "Column": { "Expression": { "SourceRef": { "Entity": "Products" } }, "Property": "ProductName" } },
          "Function": 3
        }
      }
    }
  },
  "selector": {
    "data": [{ "dataViewWildcard": { "matchingOption": 0 } }],
    "metadata": "Products.ImageUrl"
  }
}

Clickable images. Pair an image column with a webURL rule (Type 5) or place it in a Web URL data-category column to make the rendered image a link. A Web URL data-category value on the same cell is not double-linked (phishing guard).

Image diagnostics:

Totals, subtotals, and the matrix total slot

The data selector's dataViewWildcard.matchingOption controls which cells a value rule (backColor, fontColor, icon, webURL) targets:

• Use matchingOption: 1 (the default) for ordinary cell formatting; use 0 or 2 to extend or restrict a rule to totals — honored only on the tableEx / pivotTable visuals.

• A value rule with matchingOption: 1 does not color totals; add a second rule (or switch to 0) if totals must match.

• On a matrix, the total object's fontColor is itself a CF slot (behaves like values.fontColor). Static total colors use rowTotal / columnTotal (and subTotals) — see table.md § Table/Matrix Formatting Regions (see table.md, section tablematrix-formatting-regions).

Column width — not conditionally formattable

Power BI has no conditional/measure-driven column width. Width is a static layout value, not a CF target — there is no fx ("Format by field value" / rules / gradient) entry for width on tableEx or pivotTable, and it does not belong with the seven CF types above. powerbi-report-author validate rejects a data-bound expression placed in columnWidth.value.

For the supported static per-column width shape and alternatives, see table.md § Column width (static) (see table.md, section column-width-static). To convey magnitude inside a fixed-width column, use a data bar.

Chart color inheritance

Do not duplicate a conditional expression when the visual can inherit the conditionally formatted series color.

Line, marker, legend, and series-label consistency

For line/area charts:

• dataPoint.fill is the direct full-series line-color target.

• With a Category-role selector on a single-series non-combo chart, dataPoint.fill is also the per-category marker-color target. It supports gradients, rules, and field-value colors. Set lineStyles.strokeColor independently when the line must remain static.

• lineStyles.strokeColor is the per-category line-segment target for a single non-combo line series.

• lineStyles.markerColor supports static marker styling. Omit it when using per-category marker colors through dataPoint.fill.

• If markers should follow one conditionally formatted full-series line color, omit separate marker formatting and use the visual's match/inherit behavior.

• legend.matchLineColor: true makes the legend symbol follow the line rather than the marker.

• seriesLabels.seriesMatchColor: true makes end-of-line series labels follow the series color.

• lineStyles.areaMatchStrokeColor: true makes shaded area follow the conditionally formatted line.

Avoid:

• Do not place per-category marker conditional formatting in lineStyles.markerColor; use Category-scoped dataPoint.fill.

• Do not set lineStyles.markerColor alongside Category-scoped dataPoint.fill, because the explicit marker color overrides the per-category colors.

• Do not use dataViewWildcard for per-category markers; use { "data": [{ "roles": ["Category"] }] }.

• Do not apply the per-category marker pattern to combo charts, multiple Y measures, or charts with a categorical legend.

"legend": [
  {
    "properties": {
      "matchLineColor": {
        "expr": { "Literal": { "Value": "true" } }
      }
    }
  }
],
"seriesLabels": [
  {
    "properties": {
      "seriesMatchColor": {
        "expr": { "Literal": { "Value": "true" } }
      }
    }
  }
],
"lineStyles": [
  {
    "properties": {
      "areaMatchStrokeColor": {
        "expr": { "Literal": { "Value": "true" } }
      }
    }
  }
]

The legend's labelColor property controls legend text, not category identity. Do not apply a second conditional rule to legend.labelColor to synchronize categories.

Category consistency across visuals

To keep the same category color across bar/column, line, pie/donut, and treemap visuals:

1. Create one text measure or column that returns a color for the current category.

2. Apply that same field-value expression to each visual's direct color target.

3. Keep the category/legend field consistent across visuals.

4. Let each visual's legend symbol inherit the resulting data or series color.

This is data-driven category consistency. Static per-measure colors use metadata selectors instead; see color-strategy.md (see color-strategy.md, section pattern-cross-visual-measure-color-consistency).

Line segment limitation

Conditional line-segment coloring applies to a single line series and uses a category-role selector:

"selector": {
  "data": [{ "roles": ["Category"] }]
}

Adding a categorical legend creates multiple line series and disables segment formatting. With multiple series, author full-series color on dataPoint.fill with the series-role selector:

"selector": {
  "data": [{ "roles": ["Series"] }],
  "hierarchyMatching": 1
}