Topic       : TOS - The Operating System
Author      : 
Version     : tos.hyp (December 19, 2008)
Subject     : Programmieren/Atari
Nodes       : 3010
Index Size  : 93790
HCP-Version : 5
Compiled on : Atari
@charset    : atarist
@lang       : 
@default    : Title
@help       : 
@options    : +g -i -s +x +zz -t4
@width      : 70
View Ref-File8.11.14  xfrm_popup                                                TOS

 Name:         »XForm popup« - Manage a popup menu (extended MagiC 
               version).

 Opcode:       135

 Syntax:       int16_t xfrm_popup( OBJECT *tree, int16_t x, int16_t y, 
               int16_t firstscrlob, int16_t lastscrlob, int16_t 
               nlines, void cdecl (*init)(OBJECT *tree, int16_t 
               scrollpos, int16_t nlines, void *param), void *param, 
               int16_t *lastscrlpos )

 Description:  The call xfrm_popup displays a popup menu on the 
               screen, and takes on its management. The followiong 
               apply:

                Parameter  Meaning

                tree       Address of the object tree
                x          X-coordinate, and
                y          Y-coordinate around which the box is to be 
                           centered
                firstscrlob Object index of the first scrollable 
                           object
                lastscrlob Object index of the last scrollable object
                nlines     Number of lines actually present
                init       Callback routine for translating the 
                           objects. tree, param and nlines are the 
                           parameters that were passed in xfrm_popup. 
                           scrollpos specifies the current scroll 
                           position. It lies at: 0..(nlines- 
                           (lastscrlob-firstscrlob+1). If the popup 
                           should not scroll, init == NULL must be 
                           passed.
                param      User-defined parameter
                lastscrlpos Last scroll position

               Note: If the parameters x and y have the value 0, then 
               the corresponding values from the object structure will 
               be respected, and the centering is abandoned. At all 
               times the function ensures that the complete popup is 
               displayed on the screen.

               Selectable objects must have the status SELECTABLE and 
               non-selectable objects the status DISABLED assigned. 
               The object with the index 0 in the object tree should 
               be of the type G_BOX or G_IBOX.

                 1. The object tree is initialized automatically by a 
                    call of the init routine before the first drawing 
                    action.

                 2. The variable scrollpos need not be initialized, as 
                    the system always start at scrollpos 0.

                 3. The init routine is responsible for initializing 
                    the first and/or last scroll object with an arrow.

                 4. The scrollable objects are firstscrlob ... 
                    lastscrlob. The object indices must be consecutive 
                    numbers. The objects must lie directly below each 
                    other and all must have the same size.

 Return value: The function returns the index of the selected object 
               from the popup menu, else the value -1.

 Availability: The function is available as of MagiC 5.03.

 Group:        Form library

 See Also:     Binding   OBJECT   form_popup