Whenever a check box is clicked by the user, the check box’s value is toggled and its callback procedure is invoked. A callback procedure is provided as an initialization argument when each check box is created.
constructor
[labellabel][parentparent][ [callbackcallback][stylestyle][valuevalue][fontfont][enabledenabled][vert-marginvert-margin][horiz-marginhoriz-margin][min-widthmin-width][min-heightmin-height][stretchable-widthstretchable-width][stretchable-heightstretchable-height]])
If & occurs in label (when label is a string), it is specially parsed as for button% .
The callback procedure is called (with the event type 'check-box) whenever the user clicks the check box.
If style includes 'deleted, then the check box is created as hidden, and it does not affect its parent’s geometry; the check box can be made active later by calling parent’s add-child method.
If value is true, it is passed to set-value so that the box is initially checked.
The font argument determines the font for the control. For information about the enabled argument, see window<%> . For information about the horiz-margin and vert-margin arguments, see subarea<%> . For information about the min-width, min-height, stretchable-width, and stretchable-height arguments, see area<%> .
Otherwise, sets the bitmap label for a bitmap check box. Since label is a bitmap, if the bitmap has a mask (see get-loaded-mask in bitmap% ) that is the same size as the bitmap, then the mask is used for the label. Modifying a bitmap while it is used as a label has an unspecified effect on the displayed label. The bitmap label is installed only if the control was originally created with a bitmap label.
The check box’s state can be changed by the user clicking the control, and such changes do not go through this method; use the control callback procedure (provided as an initialization argument) to monitor state changes.