Expression Function

linearGradientImage()

This is the expression function that generates the PNG gradient image. It allows specification of many values to produce gradients that match your color schemes.

Returns: Document

hexColors (List of Text String): The list of colors in the gradient, as hexadecimal, e.g. { "#FFAA00", "#EE5500", "#EEEEEE" }

distribution (List of Number (Floating Point)): The distribution positions of the colors in the gradient change as a percentage (value between 0 and 1), e.g. { 0.0, 0.2, 1.0 }

width (Number (Integer)): The width of the image in pixels

height (Number (Integer)): The height of the image in pixels

horizontal (Boolean): If true, the gradient will be oriented horizontally instead of vertically

targetFolder (Folder): The Appian Folder to store (and cache) the image

Example

a!imageField(
  label: "Result",
  labelPosition: "ABOVE",
  images: {
    a!documentImage(
      document: linearGradientImage(
        hexColors: { "#cc3300", "#ff9966", "#ffcc00", "#99cc33", "#339900" },
        distribution: { 0, 0.25, 0.5, 0.75, 1 },
        width: 500,
        height: 200,
        horizontal: false,
        targetFolder: cons!GRAD_FOLDER_DEFAULT,
      )
    )
  },
  size: "LARGE",
  isThumbnail: false,
  style: "STANDARD"
)

This would produce an image named: linear_cc3300_ff9966_ffcc00_99cc33_339900_0.0_0.25_0.5_0.75_1.0_500_200_vertical.png

Expression example gradient

Note

The filename is a concatenation of the arguments to the expression function, producing a consistently named image for the same arguments. This is how the plugin finds and returns existing images instead of regenerating them each time. As such, if you move, rename, or delete the Document, the plugin will regenerate the image using this long filename again.