System color support

System color support - automatic

You can set the color properties for the various window elements to use system colors. When you use this setting, Dexterity automatically assigns colors for window items based on the current operating system settings.

Color properties

You can choose System as a color choice when you specify the FontColor, BackColor or LineColor visual properties for objects. If system colors are not supported for a particular color property or operating system, a default color is used.

The following chart lists the color properties and shows the operating system color setting that will be used when the color property is set to System.

Property	Windows operating system color
FontColor	Window font color
BackColor (For editable fields)	Window color when editable; 3D Object color when not editable
BackColor (For static items)	3D Object color
LineColor	Based upon 3D Object color

To give your application the best appearance when using system colors, we recommend that you set the BackColor property for windows to True and choose System as the FontColor and BackColor for all editable fields. We also recommend that you set the line color to System for any separator lines or group boxes.

Window background color

System colors are also used for the window background color. In the Windows operating system, the window background color used is determined by the operating system’s 3D Object color setting.

If you use pictures or native pictures in your application, you may want the picture’s background to blend automatically with whatever window background color a user selects. For example, the lookup button shown in the following illustration uses native pictures for the up and down states. If the user changes the operating system’s background color to a color other than light gray, the lookup button won’t blend with the new background color.

To make the lookup button blend automatically with the background color, you must do the following:

Set the BackColor visual property for the push button to System.
Use a special color for the background of the pictures that appear on the push button. This special color is the light gray shade that appears in the 16-color palette for the Windows Paint application.

The RGB values for this color are Red=192, Green=192 and Blue=192 on a scale of 255. If you use a paint or draw application that specifies RGB colors as percentages, use the following percentages: Red=75.294%, Green=75.294% and Blue=75.294%.

When the BackColor property has been set to System, any part of the picture that uses the special light gray color will instead be displayed with the system’s background color. If the lookup button shown in the previous example was drawn using the special light gray color, and the BackColor property for the lookup button was set to System, the lookup button would blend with the window background color.

Any pictures or native pictures can be made to blend with the window background color by using the special shade of gray in the picture and setting the BackColor property for the picture or control to System.