BB___BACKCOLOR

BACKCOLOR

Description

  • For use with graphics windows and graphicboxes, BACKCOLOR is used to set the color to fill shapes and the background of graphics text.


Syntax

  • Color commands are NOT case sensitive.
  1. #handle "backcolor color" - a graphics window
  2. #handle.ext "backcolor color" - a graphicbox
    Color can be specified using any one of the standard system colors or using the RGB pure color method. See colors. e.g.:
    #handle.ext "backcolor cyan"
    #handle.ext "backcolor 127 0 127"
    'using a variable for value of color
    color$="darkgray"
    rgb$="155 30 155"
    #handle.ext "color "; color$
    #handle.ext "color "; rgb$

Caution!

  • There is a 'quirk' when using the BACKCOLOR command with a graphicbox control. (This does not apply when using the command in a graphics window). The behavior is such that, when a window is resized or minimized and restored, the background of the graphicbox itself will be painted with the last color specified in a backcolor statement. This happens even though you fully expect the background to have no color and have not used a FILL command to apply a background color to the graphicbox control.

  • The way to prevent this unexpected behavior from occurring is to specify a fill color for the graphicbox. To keep a neutral background, use a fill color of white or buttonface.

Hints

  • Color set with color commands can be changed with each new graphic command. Run this example:
    nomainwin
 
    WindowWidth=400
    WindowHeight=300
 
    open "Change Colors Demo" for graphics as #g
    #g "trapclose [quit]"
    'put the pen down, give it a size and place it
    #g "down; size 2; place 50 50"
    'set the backcolor of first shape
    #g "backcolor red"
    'draw a filled circle
    #g "circlefilled 50"
    'set the backcolor of second shape and place it
    #g "backcolor yellow; place 100 100"
    'draw a filled circle with different pen color
    #g "color blue; circlefilled 50"
    'set the backcolor of third shape and place it
    #g "backcolor blue; place 150 150"
    'draw a filled circle with a different pen color
    #g "color pink; circlefilled 50"
 
    wait
 
[quit]
    close #g
    end

Example

An example of the command in a graphics window.
    nomainwin
 
    WindowWidth=400
    WindowHeight=300
 
    open "Backcolor Demo" for graphics as #g
    #g "trapclose [quit]"
    'put the pen down and place it in the center of the window
    #g "down; home"
    'set the backcolor
    #g "backcolor red"
    'draw a filled circle
    #g "circlefilled 50"
    'show text with red backcolor
    #g "place 20 200;\The circle is filled with the backcolor red."
    #g "place 20 230;\The color behind this text is the backcolor red."
    wait
 
[quit]
    close #g
    end

An example of the command in a graphicbox control.
    nomainwin
 
    WindowWidth=400
    WindowHeight=300
 
    graphicbox #g.gb 0, 0, 390, 270
    open "Backcolor Demo in Graphicbox" for graphics as #g
    #g "trapclose [quit]"
    'put the pen down and place it in the center of the window
    #g.gb "down; home"
    'set the backcolor
    #g.gb "backcolor blue"
    'draw a filled circle
    #g.gb "circlefilled 50"
    wait
 
[quit]
    close #g
    end

An example combining all three color commands in a graphics window.
    nomainwin
 
    WindowWidth=400
    WindowHeight=300
 
    open "All Color Demo" for graphics as #g
    #g "trapclose [quit]"
 
    'fill window with color
    #g "fill cyan"
    'set the pen color
    #g "color red"
    'set the backcolor
    #g "backcolor yellow"
    'put the pen down and place it in the center of the window
    #g "down; home"
    'draw a filled circle
    #g "circlefilled 40"
    'draw some text
    #g "place 20 20;\The cyan window color is set by FILL command."
    #g "\\The red text color and the red outline of the circle"
    #g "\is set with the COLOR command."
    #g "place 20 200;\The circle is filled with the BACKCOLOR yellow."
    #g "place 20 230;\The color behind the text is the BACKCOLOR yellow."
    #g "flush" 'make graphics stick
    wait
 
[quit]
    close #g
    end

Useful Functions

Place a useful function using this keyword here