4D Doc Center : OBJECT SET RGB COLORS

4D v13.4

OBJECT SET RGB COLORS


OBJECT SET RGB COLORS ( {* ;} object ; foregroundColor ; backgroundColor {; altBackgrndColor} )

Parameter	Type	Description
*	Operator	If specified, Object is an Object Name (String) If omitted, Object is a Field or a Variable
object	Form object	Object Name (if * is specified), or Field or Variable (if * is omitted)
foregroundColor	Longint	RGB color value for Foreground color
backgroundColor	Longint	RGB color value for Background color
altBackgrndColor	Longint	RGB color value for Alternating background color

Description

The OBJECT SET RGB COLORS command changes the foreground and background colors of the objects specified by the object parameter and the optional * parameter. When the command is applied to a List box object, an additional parameter lets you modify the alternating color of the rows.

If you specify the optional * parameter, you indicate an object name (a string) in object. If you omit the optional * parameter, you indicate a field or a variable in object. In this case, you specify a field or variable reference (field or variable objects only) instead of a string. For more information about object names, see the section Object Properties.

The optional altBackgrndColor parameter lets you set an alternate background color for even-numbered rows. This parameter is only used when the object specified is a List box or a column of the List box. When this parameter is used, the backgroundColor parameter is only used for odd-numbered rows. Using alternating colors makes lists easier to read.

If object specifies a List box object, alternating colors are used for the entire List box. If object specifies a column of the List box, only the column will use the colors set.

You indicate RGB color values in foregroundColor, backgroundColor and altBackgrndColor. An RGB value is a 4-byte Long Integer whose format (0x00RRGGBB) is described in the following table (bytes are numbered from 0 to 3, from right to left):

Byte	Description
3	Must be zero if absolute RGB color
2	Red component of the color (0..255)
1	Green component of the color (0..255)
0	Blue component of the color (0..255)

The following table shows some examples of RGB color values:

Value	Description
0x00000000	Black
0x00FF0000	Bright Red
0x0000FF00	Bright Green
0x000000FF	Bright Blue
0x007F7F7F	Gray
0x00FFFF00	Bright Yellow
0x00FF7F7F	Red Pastel
0x00FFFFFF	White

Alternatively, you can specify one of the “system” colors used by 4D for drawing objects whose colors are set automatically. The following predefined constants are provided by 4D:

Constant	Type	Value
Background color	Longint	-2
Dark shadow color	Longint	-3
Disable highlight item color	Longint	-11
Foreground color	Longint	-1
Highlight menu background color	Longint	-9
Highlight menu text color	Longint	-10
Highlight text background color	Longint	-7
Highlight text color	Longint	-8
Light shadow color	Longint	-4

These colors (on a standard system) are shown here:

WARNING: These automatic colors are system dependent. If you change your system colors, 4D will adjust its automatic colors accordingly. Use the automatic color values for setting objects to the system colors, not for setting them to the example colors shown above.

Example 1

This form contains the two non-enterable variables vsColorValue and vsColor as well as the three thermometers: thRed, thGreen, and thBlue.

Here are the methods for these objects:

  ` vsColorValue non-enterable Object Method

 Case of

    :(Form event=On Load)

       vsColorValue:="0x00000000"

 End case

  ` vsColor non-enterable variable Object Method

 Case of

    :(Form event=On Load)

       vsColor:=""

       OBJECT SET RGB COLORS(vsColor;0x00FFFFFF;0x0000)

 End case

 

  ` thRed Thermometer Object Method

 CLICK IN COLOR THERMOMETER

 

  ` thGreen Thermometer Object Method

 CLICK IN COLOR THERMOMETER

 

  ` thBlue Thermometer Object Method

 CLICK IN COLOR THERMOMETER

The project method called by the three thermometers is:

  ` CLICK IN COLOR THERMOMETER Project Method

 OBJECT SET RGB COLORS(vsColor;0x00FFFFFF;(thRed<<16)+(thGreen<<8)+thBlue)

 vsColorValue:=String((thRed<<16)+(thGreen<<8)+thBlue;"&x")

 If(thRed=0)

    vsColorValue:=Substring(vsColorValue;1;2)+"0000"+Substring(vsColorValue;3)

 End if

Note the use of the Bitwise Operators for calculating the color value from the thermometer values.

When executed, the form looks like this:

Example 2

Changing to transparent background with a light font color:

OBJECT SET RGB COLORS(*;"myVar";Light shadow color;Background color none)