color value (e.g. "#FF00A7") as view label as well as text-box in edit mode
add a color box beside that shows a little square filled with the color
in edit mode a click on the color box will open a popup with a detailed color editor form.
The color editor form may be offered as reusable widget so it can also be used directly and outside the popup.
The color editor popup should offer RGB as well as HSB mode with the individual 3 values.
The color editor should offer a rectangle with the entire color scheme to select from.
The color editor may offer a vertical slice with the current color in a brightness range to select from.
The color editor may offer a palette with a number of predefined colors to select from. The user may even modify the predefined colors to his personal favor and store them in his client (in web via cookie).
We will create a datatype Color that is used as value to get and set. It should have getRed(), getGreen(), getBlue(), getHue(), getSaturation(), getBrightness(), etc.
We need to implement a color picker widget: