DataDescriptor

The object for providing the data type, data formatting, and label for a field in a table.

Declaration

object DataDescriptor

Properties

Name	Type	Description
`dataType` Required	string	The data type. Valid values: `string`. Short text values, shorter than a typical sentence. Column widths are calculated differently for `string` and `text` data. `string` supports data values that are provided as strings or as FormattedText. `text`. Long text values, as long as a typical sentence or longer. Column widths are calculated differently for `string` and `text` data. `text` supports data values that are provided as strings or as FormattedText. `image`. Image URLs, starting with `bundle://` for an image provided in the same location as `article.json`, or starting with `http://` or `https://` for remote images. The images are displayed in the table. See Preparing Image, Video, Audio, Music, and ARKit Assets. To control image size, use a ImageDataFormat object as the value of the `format` property. `number`. Numerical values where the more specific data type is not known. `integer`. Integer values. `float`. Floating-point values. To format the value, use a FloatDataFormat in the `format` property.
`key` Required	string	The name of this data descriptor. In a data record, you use this name as the key in a key-value pair, where the value is the data itself. This key must be unique across data descriptors in this data record store. See RecordStore.
`label` Required	(`FormattedText` \| string)	The text to appear in the table header for this data category. This text can be provided as a string or a FormattedText object.
`format`	`DataFormat`	The object that sets some additional formatting preferences if you are using the `float` or `image` data type. For example, use a FloatDataFormat object in this property to control rounding, or use an ImageDataFormat to control image size.
`identifier`	string	A unique identifier for this data descriptor. If used, identifiers must be unique across descriptors in this data record store. An identifier is required if you want to sort your table by any order other than the order in which the records are provided.

Mentioned in

Defining and Using Table Styles

Discussion

A DataDescriptor object defines the data in a table by including basic information such as data type, data format, and a name for this set of data that identifies the kind of information it is. For example, the name could be “product number” or “release year”. An array of all the data descriptors for a table is located in the table’s RecordStore.

Example

{
  "components": [
    {
      "role": "datatable",
      "showDescriptorLabels": true,
      "sortBy": [
        {
          "descriptor": "id-name",
          "direction": "descending"
        }
      ],
      "data": {
        "descriptors": [
          {
            "identifier": "id-image",
            "key": "image",
            "label": {
              "type": "formatted_text",
              "text": "Image"
            },
            "format": {
              "type": "image",
              "maximumWidth": "50pt"
            },
            "dataType": "image"
          },
          {
            "identifier": "id-name",
            "key": "name",
            "label": {
              "type": "formatted_text",
              "text": "Name"
            },
            "dataType": "string"
          },
          {
            "identifier": "id-occupation",
            "key": "occupation",
            "label": "Occupation",
            "dataType": "string"
          }
        ],
        "records": [
          {
            "image": "bundle://image-1.jpg",
            "name": "Amelia Earhart",
            "occupation": "Pilot"
          },
          {
            "image": "bundle://image-2.jpg",
            "name": "Grace Hopper",
            "occupation": "Computer Scientist"
          }
        ]
      }
    }
  ]
}