.\"*************************************************************************** .\" Copyright 2018-2019,2020 Thomas E. Dickey * .\" Copyright 1998-2010,2017 Free Software Foundation, Inc. * .\" * .\" Permission is hereby granted, free of charge, to any person obtaining a * .\" copy of this software and associated documentation files (the * .\" "Software"), to deal in the Software without restriction, including * .\" without limitation the rights to use, copy, modify, merge, publish, * .\" distribute, distribute with modifications, sublicense, and/or sell * .\" copies of the Software, and to permit persons to whom the Software is * .\" furnished to do so, subject to the following conditions: * .\" * .\" The above copyright notice and this permission notice shall be included * .\" in all copies or substantial portions of the Software. * .\" * .\" THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS * .\" OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * .\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. * .\" IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, * .\" DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR * .\" OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR * .\" THE USE OR OTHER DEALINGS IN THE SOFTWARE. * .\" * .\" Except as contained in this notice, the name(s) of the above copyright * .\" holders shall not be used in advertising or otherwise to promote the * .\" sale, use or other dealings in this Software without prior written * .\" authorization. * .\"*************************************************************************** .\" .\" $Id: menu_driver.3x,v 1.28 2020/12/19 21:33:37 tom Exp $ .TH menu_driver 3X "" .de bP .ie n .IP \(bu 4 .el .IP \(bu 2 .. .SH NAME \fBmenu_driver\fR \- command-processing loop of the menu system .SH SYNOPSIS \fB#include \fR .sp \fBint menu_driver(MENU *\fP\fImenu\fP\fB, int \fP\fIc\fP\fB);\fP .br .SH DESCRIPTION Once a menu has been posted (displayed), you should funnel input events to it through \fBmenu_driver\fR. This routine has three major input cases: .bP The input is a form navigation request. Navigation request codes are constants defined in \fB\fP, which are distinct from the key- and character codes returned by \fBwgetch\fP(3X). .bP The input is a printable character. Printable characters (which must be positive, less than 256) are checked according to the program's locale settings. .bP The input is the KEY_MOUSE special key associated with an mouse event. .PP The menu driver requests are as follows: .TP 5 REQ_LEFT_ITEM Move left to an item. .TP 5 REQ_RIGHT_ITEM Move right to an item. .TP 5 REQ_UP_ITEM Move up to an item. .TP 5 REQ_DOWN_ITEM Move down to an item. .TP 5 REQ_SCR_ULINE Scroll up a line. .TP 5 REQ_SCR_DLINE Scroll down a line. .TP 5 REQ_SCR_DPAGE Scroll down a page. .TP 5 REQ_SCR_UPAGE Scroll up a page. .TP 5 REQ_FIRST_ITEM Move to the first item. .TP 5 REQ_LAST_ITEM Move to the last item. .TP 5 REQ_NEXT_ITEM Move to the next item. .TP 5 REQ_PREV_ITEM Move to the previous item. .TP 5 REQ_TOGGLE_ITEM Select/deselect an item. .TP 5 REQ_CLEAR_PATTERN Clear the menu pattern buffer. .TP 5 REQ_BACK_PATTERN Delete the previous character from the pattern buffer. .TP 5 REQ_NEXT_MATCH Move to the next item matching the pattern match. .TP 5 REQ_PREV_MATCH Move to the previous item matching the pattern match. .PP If the second argument is a printable character, the code appends it to the pattern buffer and attempts to move to the next item matching the new pattern. If there is no such match, \fBmenu_driver\fR returns \fBE_NO_MATCH\fR and deletes the appended character from the buffer. .PP If the second argument is one of the above pre-defined requests, the corresponding action is performed. .SS MOUSE HANDLING .PP If the second argument is the KEY_MOUSE special key, the associated mouse event is translated into one of the above pre-defined requests. Currently only clicks in the user window (e.g., inside the menu display area or the decoration window) are handled. .PP If you click above the display region of the menu: .bP a REQ_SCR_ULINE is generated for a single click, .bP a REQ_SCR_UPAGE is generated for a double-click and .bP a REQ_FIRST_ITEM is generated for a triple-click. .PP If you click below the display region of the menu: .bP a REQ_SCR_DLINE is generated for a single click, .bP a REQ_SCR_DPAGE is generated for a double-click and .bP a REQ_LAST_ITEM is generated for a triple-click. .PP If you click at an item inside the display area of the menu: .bP the menu cursor is positioned to that item. .bP If you double-click an item a REQ_TOGGLE_ITEM is generated and \fBE_UNKNOWN_COMMAND\fR is returned. This return value makes sense, because a double click usually means that an item-specific action should be returned. It is exactly the purpose of this return value to signal that an application specific command should be executed. .bP If a translation into a request was done, \fBmenu_driver\fR returns the result of this request. .PP If you clicked outside the user window or the mouse event could not be translated into a menu request an \fBE_REQUEST_DENIED\fR is returned. .SS APPLICATION-DEFINED COMMANDS .PP If the second argument is neither printable nor one of the above pre-defined menu requests or KEY_MOUSE, the drive assumes it is an application-specific command and returns \fBE_UNKNOWN_COMMAND\fR. Application-defined commands should be defined relative to \fBMAX_COMMAND\fR, the maximum value of these pre-defined requests. .SH RETURN VALUE \fBmenu_driver\fR return one of the following error codes: .TP 5 .B E_OK The routine succeeded. .TP 5 .B E_SYSTEM_ERROR System error occurred (see \fBerrno\fR(3)). .TP 5 .B E_BAD_ARGUMENT Routine detected an incorrect or out-of-range argument. .TP 5 .B E_BAD_STATE Routine was called from an initialization or termination function. .TP 5 .B E_NOT_POSTED The menu has not been posted. .TP 5 .B E_UNKNOWN_COMMAND The menu driver code saw an unknown request code. .TP 5 .B E_NO_MATCH Character failed to match. .TP 5 .B E_REQUEST_DENIED The menu driver could not process the request. .SH SEE ALSO \fBcurses\fR(3X), \fBgetch\fR(3X), \fBmenu\fR(3X). .SH NOTES The header file \fB\fR automatically includes the header files \fB\fR. .SH PORTABILITY These routines emulate the System V menu library. They were not supported on Version 7 or BSD versions. The support for mouse events is ncurses specific. .SH AUTHORS Juergen Pfeifer. Manual pages and adaptation for new curses by Eric S. Raymond.