Kbase P163986: How to create a combo-box displaying the list of values by pressing a button?
| Autor |
Progress Software Corporation - Progress |
| Acesso |
Público |
| Publicação |
16/04/2010 |
|
Status: Unverified
GOAL:
How to create a combo-box displaying the list of values by pressing a button?
GOAL:
How to display list of values of a combo-box without using the mouse?
GOAL:
How to create a combo-box displaying the list of values by pressing a button using Procedure Editor and AppBuilder?
FACT(s) (Environment):
Win32 API - CB_SHOWDROPDOWN message to drop the list
Windows
Progress 9.x
OpenEdge 10.x
FIX:
The following code demonstrates how to create a combo box and a button to display list of values using the Procedure Editor:
&SCOPED-DEFINE CB_SHOWDROPDOWN 335
DEF BUTTON b LABEL "Show list".
DEF VAR a AS CHAR VIEW-AS COMBO-BOX LIST-ITEMS "One", "Two".
DEF FRAME f b a.
ENABLE b a WITH FRAME f.
ON 'choose':U OF b
DO:
RUN SendMessageA(a:HWND, {&CB_SHOWDROPDOWN}, 1, 0).
RETURN.
END.
WAIT-FOR WINDOW-CLOSE OF CURRENT-WINDOW.
PROCEDURE SendMessageA EXTERNAL "user32.dll":
DEFINE INPUT PARAMETER hwnd AS LONG.
DEFINE INPUT PARAMETER umsg AS LONG.
DEFINE INPUT PARAMETER wparam AS LONG.
DEFINE INPUT PARAMETER lparam AS LONG.
END.
FIX:
The following code demonstrates how to create a combo box and a button to display list of values using the Application Builder:
&Scoped-define WINDOW-NAME C-Win
/*------------------------------------------------------------------------
File:
Description:
Input Parameters:
<none>
Output Parameters:
<none>
Author:
Created:
------------------------------------------------------------------------*/
/* This .W file was created with the Progress AppBuilder. */
/*----------------------------------------------------------------------*/
/* Create an unnamed pool to store all the widgets created
by this procedure. This is a good default which assures
that this procedure's triggers and internal procedures
will execute in this procedure's storage, and that proper
cleanup will occur on deletion of the procedure. */
CREATE WIDGET-POOL.
/* *************************** Definitions ************************** */
/* Parameters Definitions --- */
/* Local Variable Definitions --- */
/* ******************** Preprocessor Definitions ******************** */
&Scoped-define PROCEDURE-TYPE Window
&Scoped-define DB-AWARE no
/* Name of designated FRAME-NAME and/or first browse and/or first query */
&Scoped-define FRAME-NAME DEFAULT-FRAME
/* Standard List Definitions */
&Scoped-Define ENABLED-OBJECTS COMBO-BOX-1 BUTTON-1
&Scoped-Define DISPLAYED-OBJECTS COMBO-BOX-1
/* Custom List Definitions */
/* List-1,List-2,List-3,List-4,List-5,List-6 */
/* *********************** Control Definitions ********************** */
/* Define the widget handle for the window */
DEFINE VAR C-Win AS WIDGET-HANDLE NO-UNDO.
/* Definitions of the field level widgets */
DEFINE BUTTON BUTTON-1
LABEL "Button 1"
SIZE 15 BY 1.14.
DEFINE VARIABLE COMBO-BOX-1 AS CHARACTER FORMAT "X(256)":U
LABEL "Combo 1" > VIEW-AS COMBO-BOX INNER-LINES 5
LIST-ITEMS "Item 1","Item 2","Item 3"
DROP-DOWN-LIST
SIZE 16 BY 1 NO-UNDO.
/* ************************ Frame Definitions *********************** */
DEFINE FRAME DEFAULT-FRAME
COMBO-BOX-1 AT ROW 3.62 COL 23 COLON-ALIGNED WIDGET-ID 2
BUTTON-1 AT ROW 3.62 COL 51 WIDGET-ID 4
WITH 1 DOWN NO-BOX KEEP-TAB-ORDER OVERLAY
SIDE-LABELS NO-UNDERLINE THREE-D
AT COL 1 ROW 1
SIZE 80 BY 16 WIDGET-ID 100.
/* *********************** Procedure Settings ************************ */
/* Settings for THIS-PROCEDURE
Type: Window
Allow: Basic,Browse,DB-Fields,Window,Query
Other Settings: COMPILE
*/
/* ************************* Create Window ************************** */
IF SESSION:DISPLAY-TYPE = "GUI":U THEN
CREATE WINDOW C-Win ASSIGN
HIDDEN = YES
TITLE = "<insert window title>"
HEIGHT = 16
WIDTH = 80
MAX-HEIGHT = 16
MAX-WIDTH = 80
VIRTUAL-HEIGHT = 16
VIRTUAL-WIDTH = 80
RESIZE = yes
SCROLL-BARS = no
STATUS-AREA = no
BGCOLOR = ?
FGCOLOR = ?
KEEP-FRAME-Z-ORDER = yes
THREE-D = yes
MESSAGE-AREA = no
SENSITIVE = yes.
ELSE {&WINDOW-NAME} = CURRENT-WINDOW.
/* END WINDOW DEFINITION */
/* *********** Runtime Attributes and AppBuilder Settings *********** */
/* SETTINGS FOR WINDOW C-Win
VISIBLE,,RUN-PERSISTENT &n.bsp; */
/* SETTINGS FOR FRAME DEFAULT-FRAME
FRAME-NAME */
IF SESSION:DISPLAY-TYPE = "GUI":U AND VALID-HANDLE(C-Win)
THEN C-Win:HIDDEN = no.
/* ************************ Control Triggers ************************ */
&Scoped-define SELF-NAME C-Win
ON END-ERROR OF C-Win /* <insert window title> */
OR ENDKEY OF {&WINDOW-NAME} ANYWHERE DO:
/* This case occurs when the user presses the "Esc" key.
In a persistently run window, just ignore this. If we did not, the
application would exit. */
IF THIS-PROCEDURE:PERSISTENT THEN RETURN NO-APPLY.
END.
ON WINDOW-CLOSE OF C-Win /* <insert window title> */
DO:
/* This event will close the window and terminate the procedure. */
APPLY "CLOSE":U TO THIS-PROCEDURE.
RETURN NO-APPLY.
END.
&Scoped-define SELF-NAME BUTTON-1
ON CHOOSE OF BUTTON-1 IN FRAME DEFAULT-FRAME /* Button 1 */
DO:
&SCOPED-DEFINE CB_SHOWDROPDOWN 335
RUN SendMessageA(COMBO-BOX-1:HWND,{&CB_SHOWDROPDOWN}, 1, 0).
RETURN.
END.
&UNDEFINE SELF-NAME
/* *************************** Main Block *************************** */
/* Set CURRENT-WINDOW: this will parent dialog-boxes and frames. */
ASSIGN CURRENT-WINDOW = {&WINDOW-NAME}
THIS-PROCEDURE:CURRENT-WINDOW = {&WINDOW-NAME}.
/* The CLOSE event can be used from inside or outside the procedure to */
/* terminate it. */
ON CLOSE OF THIS-PROCEDURE
RUN disable_UI.
/* Best default for GUI applications is... */
PAUSE 0 BEFORE-HIDE.
/* Now enable the interface and wait for the exit condition. */
/* (NOTE: handle ERROR and END-KEY so cleanup code will always fire. */
MAIN-BLOCK:
DO ON ERROR UNDO MAIN-BLOCK, LEAVE MAIN-BLOCK
ON END-KEY UNDO MAIN-BLOCK, LEAVE MAIN-BLOCK:
RUN enable_UI.
PROCEDURE SendMessageA EXTERNAL "user32.dll":
DEFINE INPUT PARAMETER hwnd AS LONG.
DEFINE INPUT PARAMETER umsg AS LONG.
DEFINE INPUT PARAMETER wparam AS LONG.
DEFINE INPUT PARAMETER lparam AS LONG.
END.
IF NOT THIS-PROCEDURE:PERSISTENT THEN
WAIT-FOR CLOSE OF THIS-PROCEDURE.
END.
/* ********************** Internal Procedures *********************** */
PROCEDURE disable_UI :
/*------------------------------------------------------------------------------
Purpose: DISABLE the User Interface
Parameters.: <none>
Notes: Here we clean-up the user-interface by deleting
dynamic widgets we have created and/or hide
frames. This procedure is usually called when
we are ready to "clean-up" after running.
------------------------------------------------------------------------------*/
/* Delete the WINDOW we created */
IF SESSION:DISPLAY-TYPE = "GUI":U AND VALID-HANDLE(C-Win)
THEN DELETE WIDGET C-Win.
IF THIS-PROCEDURE:PERSISTENT THEN DELETE PROCEDURE THIS-PROCEDURE.
END PROCEDURE.
PROCEDURE enable_UI :
/*------------------------------------------------------------------------------
Purpose: ENABLE the User Interface
Parameters: <none>
Notes: Here we display/view/enable the widgets in the
user-interface. In addition, OPEN all queries
associated with each FRAME and BROWSE.
These statements here are based on the "Other
Settings" section of the widget Property Sheets.
------------------------------------------------------------------------------*/
DISPLAY COMBO-BOX-1
WITH FRAME DEFAULT-FRAME IN WINDOW C-Win.
ENABLE COMBO-BOX-1 BUTTON-1
WITH FRAME DEFAULT-FRAME IN WINDOW C-Win.
{&OPEN-BROWSERS-IN-QUERY-DEFAULT-FRAME}
VIEW C-Win.
END PROCEDURE.
PROCEDURE myProcedure :
/*------------------------------------------------------------------------------
Purpose:
Parameters: <none>
Notes:
------------------------------------------------------------------------------*/
END PROCEDURE.
.