Common Properties

The set of radio button common properties includes:

TITLE

Radio buttons may have titles; the title typically appears to the right of the button. The TITLE phrase is used to specify the title. A key letter may be specified in the title. See Common Screen Options in the ACUCOBOL-GT Reference Manual for more information.

VALUE

Radio buttons have numeric values. A value of 0 indicates an unselected radio button. A value of 1 indicates a selected radio button.
Note: Radio buttons cannot have array elements in a VALUE or USING phrase. The compiler detects and disallows such usage, and an error message is displayed at compile time.

SIZE

The LINES and SIZE values describe the size of the radio button's title area. The LINES value describes the height of the title area, in lines. The SIZE value specifies the width of the title area, using the width of the 0 (zero) character as the base unit. Added to the title area is the overhead needed for the actual button. This usually adds several character positions to the width and may affect the height if the button is taller than the title's font.

When the program executes on a non-graphical system, the values specified in the CLINES and CSIZE phrases, if present, replace the values specified by the LINES and SIZE phrases.

The default value of LINES is 1. The default value of SIZE is computed by measuring the length of the title using the button's font and dividing by the width of the "0" character. Thus, the default width of a radio button exactly occupies the space its text takes up on the screen.

When used with the BITMAP style, the LINES and SIZE values have a different meaning. The values are the number of pixels in the height and width of the bitmap image.If omitted, the default values depend on the host system. Under Microsoft Windows, the default LINES value is 15 and the default SIZE value is 16. These values correspond to the size of buttons typically found on a toolbar. See Bitmap Buttons for details.

COLOR

Radio buttons use both the foreground and background colors specified. If either is omitted, the corresponding color of the button's owning subwindow is used.

Bitmap radio buttons don't use the specified colors. Instead, the colors are derived from the bitmap and the system defaults for push buttons.

EVENT-LIST, EXCLUDE-EVENT-LIST

EVENT-LIST is an exclusive list of events that are either sent to or withheld (blocked) from the program depending on the value of EXCLUDE-EVENT-LIST. See Common Screen Options for more information.

STYLES

BITMAP This style causes the radio button to be drawn with a bitmap instead of its usual appearance. See Bitmap Buttons for a complete description.
FRAMED This style is used only with bitmap buttons. It requests that a thin frame be drawn around the button. Typically this appears as a thin black line. Not all systems support frames, in which case the request is ignored. By default, buttons are framed under Windows NT/Windows 2000.
UNFRAMED This style is used only with bitmap buttons. It requests that the button be drawn without a frame. Not all systems support unframed buttons, in which case the request is ignored. By default, buttons are not framedunder Windows 98.
SQUARE This style is used only with framed bitmap buttons. It forces the button to have square corners. Without this style, the button will have slightly rounded corners.
SELF-ACT This style creates a self-activating radio button. The behavior of the SELF-ACT radio button is the same as that of the SELF-ACT push button. Self-activating radio buttons return control to the previously active control or window when they are clicked. Usually, you will want to use the NOTIFY style in conjunction with SELF-ACT so that your program is informed whenever the radio button is clicked. See Push Button for more information.
NOTIFY This style tells the runtime to generate a CMD-CLICKED event whenever the value of the radio button is changed by the user. This allows your program to respond immediately to the change. In essence, the radio button will now act like a combination radio button and push button. Without the NOTIFY style, the radio button remains active after it has been changed (exception: see SELF-ACT, above).
NO-GROUP-TAB Normally, radio buttons that belong to a button group treat the Tab and Backtab keys in a special fashion. Any time a radio button has a non-zero GROUP special property, it acts as if it also has the NO-TAB style unless it is the group leader. The group leader is the radio button that is currently "on," or the first radio button in the group if they are all "off." The effect is that when you tab to a radio button group, control passes to the button that is on, or to the first button in the group if none is on. Note that the NO-GROUP-TAB style suppresses this special handling.
LEFT-TEXT Radio buttons with this style display their text to the left of the box instead of to the right. Note that if you use this style and try to vertically align several radio buttons, the buttons may not align vertically. This is because the default behavior of the run-time is to place the right edge of the button at the minimum distance needed from its left edge to accommodate the control's text. This results in the buttons being placed in different columns, depending on the text of each control. Supplying a uniform width using the SIZE property overrides this behavior.
FLAT On Windows systems, this style creates a radio button without visible borders. On non-Windows systems, this style has no effect.
MULTILINE This style causes the radio button to have a multi-line title. When the MULTILINE style is applied, the radio button’s title text is automatically word wrapped to fit the radio button’s size. You can force a line break in the text by embedding an ASCII line feed character(h“0A”). The MULTILINE style is ignored in character-based environments.
VTOP This style causes the title text to be vertically aligned with the top of the control's area. By default, the title text is vertically aligned to the center of the control's area.
Parent topic: Radio Button