Office of Digital Humanities

DigHT 310
Colors in LiveCode
Activity

Two types of color mixing: subtractive and additive

Nice overview of these concepts (YouTube)

In LiveCode, colors are defined in one of three ways:

• name - See the colorNames property (predefined colors)
  In the message box try this:

   put the colorNames

• RGB values - 3 integers, separated by commas in the range 0-255
• Hexidecimal values - A string preceded by # followed by three hex values

To change colors use the set command, followed by a valid color reference:

  set the backgroundcolor of graphic 1 to "Gray100" --color name
  set the backgroundColor of graphic 1 to 120,120,220 --RGB triplet
  set the backgroundColor of graphic 1 to "#1050AF" -- hex value

Objects have up to 8 color properties that can be set:

• the foregroundColor (synonym: the textColor)
• the backgroundColor
• the hiliteColor (the background color of highlighted text)
• the borderColor (only when the threeD property is false)
• the topColor (only when the threeD property is true)
• the bottomColor (only when the threeD property is true)
• the shadowColor (only when the shadow property is true)
• the focusColor (for focus border)

These can be set manually in the Colors & Patterns pane of the property inspector, or by script, as we have seen here.

Quick Color Stack activity

(To be turned in by next class period.)

1. Create a new stack
2. Create graphic named "tester"
3. Create button "setColor"
4. Create field "colorDef"
   
   Button script:

   on mouseUp
     set the backgroundColor of graphic "tester" to fld "colorDef"
   end mouseUp
   

   Try entering some valid color references in the field and test the result

Now create a list-style field that shows the named colors recognized by the system:

5. Drag a Scrolling list field from the Tools palette and name it "colorList"
6. Message box: put the colornames into field "colorList"
7. Script of list field:

   on mouseup
     set the backgroundColor of graphic "tester" to the selectedText of me
   end mouseup
   

How to display a standard system color picker:

8. Create button "chooseColor"

   Use the answer color command in the button script:

   on mouseUp
     answer color
     set the backgroundcolor of graphic "tester" to it
   end mouseUp