1. JukeBox – transparency, flexibility, speed and comfort!
Brynjar Hasle, Chemistry as

2. Operational (business) requirements:
The client should be in charge of the server
Slick UI
Exceptional development speed (low, that is)
Transparency client-server / appserver
No extra setup required
Very small client footprint

3. Tools:
Dynamic 4GL (9.1d+)
Static 4GL
(Stateless AppServer (9.1d+))
(Aia client on webserver)
- Progress 8.x - 9.1/10.0a RDBMS

4. Basic Elements x.w y.w z.w UI_lib.p AS_lib.p
Client:
x.w
y.w
z.w
UI_lib.p
AS_lib.p
Server:
Get data: -gettemptablejoin.p
-getfieldlist.p
getfieldvalues.p (FIND)
-gettemptable (input <fill>.p) -checkcurrentchanged.p ..
Put data: -servertrans.p -runproc.p ..

5. Server, get data:
- gettemptablejoin.p: Input: - Buffers and fields Query criteria Startrow and number of rows to return
Hooks for calculated fields (input .p’s for logic)
Returns temp-table handle (and hence the data)
getfieldlist.p: Input: - Buffers and fields Query criteria Returns fieldlist (f.ex to populate drop-down)
- gettemptable.p (input .p, output temp-table handle)

6. Server, put data:
- servertrans.p: Input: - Trans header and trans values Temp-table struct
Dynamic FK validation
Hooks for custom validation / updates
Assign defaults
Returns completed temp-table (option)
Trans.header:
Buffer
Operation
Field list
Opt.val.proc
Trans.values:
- Field value list

7. AS_lib, main methods:
- GetTempTableJoin( Input: List of buffers and fields, rows-to-batch,startrow and query criteria).
Checks for appserver / client server and passes on the input parameters pluss sessionid to gettemptablejoin.p
- DoCreate(Input buffer,fields and values).
- DoUpdate(Input buffer,criteria,fields and values).
DoDelete(Input buffer,criteria).
Populate transaction temp-tables.
- DoCommit(true/false).
Checks for appserver and passes transaction temp-tables to servertrans.p. True/False: receive completed buffer back

8. UI_lib: Implements standard events
and methods. Keeps run-time state for UI objects.
”Objects”:
NewBrowse(..)
-NewQuery(..)
-NewFieldMap(..)
(browse buffer pluss add.
ttObject
ttEvent
ttObjectLink
ttAttribute
info on input/display fields)
-NewToolbar(..)
-NewBrowseDropDown(..)
-NewBrowseFillIn(..) -NewFilter(..) ..
Standard methods:
DisplayRecord, SaveRecord, OpenQuery,etc.

9. Additional handy stuff:
- ResizeLib.p
- Dynamic lookup
- src/adm2/dyntreeview.w (slightly altered)
- from smartpak/adm2/cal.w (altered)
- Microsoft OCX tab-folder -

10. Coding example:
Rectangles are used to represent screen objects that are created. In this example a toolbar and a browser. All relevant code for this simple window is in one procedure, InitWindow.
Only the libraries (AS,UI and Resize are supporting this .w file – no includes).

11. Procedure InitWindow:
DO WITH FRAME {&FRAME-NAME}:
hBrowse = DYNAMIC-FUNCTION("NewBrowse", /* Create a browse object (New!) */
rectBrowse:HANDLE, /* Rectangle to define coordinates for browse */
100, /* Rows to batch */
"", /* Browse properties, ie MULTIPLE,NUM-LOCKED-COLUMNS, etc */
"pccMemberShipType;MemberShipTypeName;MemberShipTypeCost",
/* Buffers and fields: <buffer1>;<field1>;<field2>..,<buffer2>;.. No fields gives all*/
"WHERE iCompanyId = " + STRING(DYNAMIC-FUNCTION("getCompanyId")),
"") /* Misc - for something I might need in next version.. */
hFieldMap = DYNAMIC-FUNCTION("NewFieldMap", /* A fieldmap object holds extra info for display and input fields (fill-ins)
and their corresponding buffer columns return handle equals the buffer handle */
hBrowse:QUERY,
FRAME {&FRAME-NAME}:HANDLE, /* Frame for the input/display fields (might not be the same frame as the browse) */
"MemberShipTypeName,MemberShipTypeCost", /* Update columns in buffer */
"MemberShipTypeName,MemberShipTypeCost", /* Corresponding input fields (fill-in..)*/
"","", /* Additional buffer and displ.fields - not updateable*/
"") /* Additional input fields (not in buffer) */
/* Assign foreign key values (not selected by the user): */
DYNAMIC-FUNCTION("setAttribute",hFieldMap,"bufferextrafields","iCompanyId").
DYNAMIC-FUNCTION("setAttribute",hFieldMap,"bufferextravalues",STRING(DYNAMIC-FUNCTION("getCompanyId"))).
DYNAMIC-FUNCTION("NewToolBar",
rectTBfile:HANDLE, /* Rectangle to define coordinates for toolbar */
"Fil", /* Corresponding menu label - no menu if blank */
"new;Ny,undo;Angre,delete;Slett,save;Lagre,excel;Eksporter til Excel",
/* Buttons / Menu items: action;label;tooltip;Method;image,action;label..
Any number of properties accepted (one ok - if predef. action) */
"maxborder") /* View and expand border rectangle to span frame */
DYNAMIC-FUNCTION("LinkAllObjects", /* Link all created objects. Linktype is type of "to" object,
f.ex link from browse to combo-box is combo-box link */
THIS-PROCEDURE:CURRENT-WINDOW, /* Link only objects created for current window */
TRUE, /* Replace any existing links */
"") /* Except these objects – list of handles */
DYNAMIC-FUNCTION("setCompanyHeader",THIS-PROCEDURE:CURRENT-WINDOW). /* The application should supports multiple companies */
DYNAMIC-FUNCTION("setNoResizeY", THIS-PROCEDURE:CURRENT-WINDOW, FRAME {&FRAME-NAME}:HANDLE, "rectTBfile").
DYNAMIC-FUNCTION("setOrgWinSize", THIS-PROCEDURE:CURRENT-WINDOW,200,250,0,250).
DYNAMIC-FUNCTION("initTranslation",THIS-PROCEDURE:CURRENT-WINDOW).
APPLY "value-changed" TO hBrowse. /* Since the query is opened we want to display the first record */
END.

12. Run the window:

13. Same window again:
..this time translated, resized and with different BG-color
Resize and color settings can be stored pr window pr user

14. What happened? InitWindow NewBrowse (.w)
NewBrowse (UI_lib): 1:Ask for data and def 2: Create browser
GetTT (AS_lib): - Check for appserver (reconnect if needed)
- Create and populate TT,
- Run additioaln. calc - Return TT-handle (get_tt.p)

15. Organizing server logic
Very few access points (in AS_lib) for server logic:
Generic GetTempTableJoin
Generic GetFieldList
Generic GetFieldValue(s) - FIND
RunProc, input ”mysimple.p” + custom params:
character string (for fields and values)
optional temp-table
GetTempTable (from anothersimple.p)
Always pass on the sessionid to all server routines!

16. Using runproc Update cred.limit for these customers (.w)
- List of customers
- Field/value
- ”customer_update_records.p”
RunProc (AS_lib): - Check for appserver (reconnect if needed)
Jbox_runproc.p
- Validate session - run .p
Customer_update_record.p