Optional Inputs with Defaults

The specification can provide default values for non-required inputs. In this example, the color input is optional and defaults to steelblue. In the dataset, we specify color:orange, thus the chart is orange.

Clicking the Clear Color button will remote color from the mappings, and then the default of steelblue will be used.

You can also provide a color (name or #RRGGBB) in the input box and use the Add Color button, which will add it to the mappings and update the chart.