1 /***************************************************************************
2  * Copyright (c) 2024 Microsoft Corporation
3  *
4  * This program and the accompanying materials are made available under the
5  * terms of the MIT License which is available at
6  * https://opensource.org/licenses/MIT.
7  *
8  * SPDX-License-Identifier: MIT
9  **************************************************************************/
10 
11 
12 /**************************************************************************/
13 /**************************************************************************/
14 /**                                                                       */
15 /** GUIX Component                                                        */
16 /**                                                                       */
17 /**   Screen Stack Management (Screen Stack)                              */
18 /**                                                                       */
19 /**************************************************************************/
20 
21 #define GX_SOURCE_CODE
22 
23 
24 /* Include necessary system files.  */
25 
26 #include "gx_api.h"
27 #include "gx_widget.h"
28 #include "gx_screen_stack.h"
29 
30 /**************************************************************************/
31 /*                                                                        */
32 /*  FUNCTION                                               RELEASE        */
33 /*                                                                        */
34 /*    _gx_screen_stack_pop                                PORTABLE C      */
35 /*                                                           6.1          */
36 /*  AUTHOR                                                                */
37 /*                                                                        */
38 /*    Kenneth Maxwell, Microsoft Corporation                              */
39 /*                                                                        */
40 /*  DESCRIPTION                                                           */
41 /*                                                                        */
42 /*    This function removes the topmost entry from the screen stack, and  */
43 /*    attaches the poped screen to its parent.                            */
44 /*                                                                        */
45 /*  INPUT                                                                 */
46 /*                                                                        */
47 /*    control                               Pointer of stack entry.       */
48 /*                                                                        */
49 /*  OUTPUT                                                                */
50 /*                                                                        */
51 /*    status                                Completion status             */
52 /*                                                                        */
53 /*  CALLS                                                                 */
54 /*                                                                        */
55 /*    None                                                                */
56 /*                                                                        */
57 /*  CALLED BY                                                             */
58 /*                                                                        */
59 /*    Application Code                                                    */
60 /*                                                                        */
61 /*  RELEASE HISTORY                                                       */
62 /*                                                                        */
63 /*    DATE              NAME                      DESCRIPTION             */
64 /*                                                                        */
65 /*  05-19-2020     Kenneth Maxwell          Initial Version 6.0           */
66 /*  09-30-2020     Kenneth Maxwell          Modified comment(s),          */
67 /*                                            resulting in version 6.1    */
68 /*                                                                        */
69 /**************************************************************************/
_gx_screen_stack_pop(GX_SCREEN_STACK_CONTROL * control)70 UINT  _gx_screen_stack_pop(GX_SCREEN_STACK_CONTROL *control)
71 {
72 INT        top;
73 GX_WIDGET *screen;
74 GX_WIDGET *parent;
75 
76     top = control -> gx_screen_stack_control_top;
77 
78     if (top >= 0)
79     {
80         top <<= 1;
81         screen = control -> gx_screen_stack_control_memory[top];
82         parent = control -> gx_screen_stack_control_memory[top + 1];
83 
84         /* Dettach the child widget of parent.  */
85         while (parent -> gx_widget_first_child)
86         {
87             _gx_widget_detach(parent -> gx_widget_first_child);
88         }
89 
90         /* Attach the popped screen to its parent. */
91         _gx_widget_attach(parent, screen);
92 
93         control -> gx_screen_stack_control_top--;
94 
95         return(GX_SUCCESS);
96     }
97     else
98     {
99         return(GX_FAILURE);
100     }
101 }
102 
103