Color picker

ui.ColorWell creates a swatch of a *ui.Color that opens a color picker below it, as AppKit's color well: a click, Enter or Space opens it, and Escape or a click outside closes it. Changed reports a new color.

ui.Field(c, "Tint", func() {
	ui.ColorWell(c, &app.tint)
})

ui.ColorPicker is the picker itself, to show in a panel of your own, as AppKit's color panel: a square choosing the saturation, across, and the brightness, up, of the hue its slider chooses below it, a slider of opacity, the color in hex, which the user edits, and swatches of common colors. The arrows move across the square while it has the focus, Up and Down changing the brightness and Left and Right the saturation.

ui.ColorPicker(c, &app.background)

Accessibility

Assistive technology sees a color well whose value is the color in hex, named by its Label or its field. In the picker, it sees a slider of the saturation and brightness, sliders of the hue and the opacity, a text field named "Hex", and buttons named by the swatches' colors.