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**The BrowseClass is a ViewManager with a user interface for navigating through the result set of the underlying VIEW.**

**BrowseClass Concepts**

The BrowseClass uses several related classes to provide standard browse functionality--that is, file-loaded or page-loaded lists with automatic scrolling, searching, ranging, filtering, resets, conditional colors, conditional icons, etc. These classes can be used to build other components and functionality as well.

Added to this standard functionality, is Edit-In-Place--that is, you can update the VIEW's primary file by typing directly into the browse list. No separate update procedure is required, and the updates are appropriately autoincremented, referentially constrained, and field validated.

Following are the classes that provide this browse functionality. The classes and their respective roles are:

| BrowseClass | Browse list "supervisor" class |  |
| StepClass | Scrollbar/Progress Bar base class |  |
|  | LongStepClass | Numeric Runtime distribution |
|  | RealStepClass | Numeric Runtime distribution |
|  | StringStepClass | Alpha/Lastname distribution |
|  | CustomStepClass | Custom distribution |
| LocatorClass | Locator base class |  |
|  | StepLocatorClass | Step Locator |
|  | EntryLocatorClass | Entry Locator |
|  | IncrementalLocatorClass | Incremental Locator |
|  | FilterLocatorClass | Filter Locator |
| EditClass | Edit-In-Place |  |

The BrowseClass is fully documented in the remainder of this chapter. Each related class is documented in its own chapter.

**BrowseClass Relationship to Other Application Builder Classes**

The BrowseClass is closely integrated with several other ABC Library objects--in particular the WindowManager and ToolbarClass objects. These objects register their presence with each other, set each other's properties, and call each other's methods as needed to accomplish their respective tasks.

The BrowseClass is derived from the ViewManager, plus it relies on many of the other Application Builder Classes (RelationManager, FieldPairsClass, ToolbarClass, PopupClass, etc.) to accomplish its tasks. Therefore, if your program instantiates the BrowseClass, it must also instantiate these other classes. Much of this is automatic when you INCLUDE the BrowseClass header (ABBROWSE.INC) in your program's data section. See the //Conceptual Example//.

**BrowseClass ABC Template Implementation**

The ABC Templates automatically include all the classes and generate all the code necessary to support the functionality specified in your application's Browse Procedure and BrowseBox Control templates.

The templates //derive //a class from the BrowseClass for //each //BrowseBox in the application. By default, the derived class is called BRW# where //#// is the BrowseBox control template instance number. This derived class object supports all the functionality specified in the BrowseBox template.

The derived BrowseClass is local to the procedure, is specific to a single BrowseBox and relies on the global file-specific RelationManager and FileManager objects for the browsed files. The templates provide the derived class so you can customize the BrowseBox behavior on a per-instance basis. See //Control Templates--BrowseBox// for more information.

**BrowseClass Source Files**

The BrowseClass source code is installed by default to the Clarion \LIBSRC folder. The specific BrowseClass source code and their respective components are contained in:

| ABBROWSE.INC | BrowseClass declarations |
| ABBROWSE.CLW | BrowseClass method definitions |
| ABBROWSE.TRN | BrowseClass translation strings |

**BrowseClass Conceptual Example**

The following example shows a typical sequence of statements to declare, instantiate, initialize, use, and terminate a BrowseClass object and related objects. The example initializes and page-loads a LIST, then handles a number of associated events, including searching, scrolling, and updating. When they are initialized properly, the BrowseClass and WindowManager objects do most of the work (default event handling) internally.

**   PROGRAM**

**   INCLUDE('ABWINDOW.INC')               !declare WindowManager class**

**   INCLUDE('ABBROWSE.INC')               !declare BrowseClass**

**   MAP**

**   END**

**State        FILE,DRIVER('TOPSPEED'),PRE(ST),THREAD**

**StateCodeKey  KEY(ST:STATECODE),NOCASE,OPT**

**Record        RECORD,PRE()**

**STATECODE      STRING(2)**

**STATENAME      STRING(20)**

**              END**

**             END**

**StView    VIEW(State)               !declare VIEW for BrowseSt**

**          END**

**StateQ       QUEUE                  !declare Q for LIST**

**ST:STATECODE  LIKE(ST:STATECODE) **

**ST:STATENAME  LIKE(ST:STATENAME)  **

**ViewPosition  STRING(512) **

**             END**

**GlobalErrors ErrorClass             !declare GlobalErrors object**

**Access:State CLASS(FileManager)     !declare Access:State object**

**Init          PROCEDURE**

**             END**

**Relate:State CLASS(RelationManager) !declare Relate:State object**

**Init          PROCEDURE**

**             END**

**VCRRequest  LONG(0),THREAD**

**ThisWindow CLASS(WindowManager)     !declare ThisWindow object**

**Init        PROCEDURE(),BYTE,PROC,VIRTUAL**

**Kill        PROCEDURE(),BYTE,PROC,VIRTUAL**

**           END**

**BrowseSt  CLASS(BrowseClass)        !declare BrowseSt object**

**Q          &StateQ**

**          END**

**StLocator StepLocatorClass          !declare StLocator object**

**StStep    StepStringClass           !declare StStep object**

**StWindow WINDOW('Browse States'),AT(,,123,152),IMM,SYSTEM,GRAY**

**          LIST,AT(8,5,108,124),USE(?StList),IMM,HVSCROLL,FROM(StateQ),|**

**          FORMAT('27L(2)|M~CODE~@s2@80L(2)|M~STATENAME~@s20@')**

**          BUTTON('&Insert'),AT(8,133),USE(?Insert)**

**          BUTTON('&Change'),AT(43,133),USE(?Change),DEFAULT**

**          BUTTON('&Delete'),AT(83,133),USE(?Delete)**

**         END**

** CODE**

** ThisWindow.Run()                        !run the window procedure**

**ThisWindow.Init  PROCEDURE()             !initialize things**

**ReturnValue    BYTE,AUTO**

** CODE**

** ReturnValue = PARENT.Init()             !call base class init**

** IF ReturnValue THEN RETURN ReturnValue. **

** GlobalErrors.Init                       !initialize GlobalErrors object**

** Relate:State.Init                       !initialize Relate:State object**

** SELF.FirstField = ?StList               !set FirstField for ThisWindow**

** SELF.VCRRequest &= VCRRequest           !VCRRequest not used**

** SELF.Errors &= GlobalErrors             !set error handler for ThisWindow**

** Relate:State.Open                       !open State and related files**

** !Init BrowseSt object by naming its LIST,VIEW,Q,RelationManager & WindowManager**

** BrowseSt.Init(?StList,StateQ.ViewPosition,StView,StateQ,Relate:State,SELF)**

** OPEN(StWindow)**

** SELF.Opened=True**

** BrowseSt.Q &= StateQ                    !reference the browse QUEUE**

** StStep.Init(+ScrollSort:AllowAlpha,ScrollBy:Runtime)!initialize the StStep object**

** BrowseSt.AddSortOrder(StStep,ST:StateCodeKey)       !set the browse sort order**

** BrowseSt.AddLocator(StLocator)          !plug in the browse locator**

** StLocator.Init(,ST:STATECODE,1,BrowseSt)!initialize the locator**

**BrowseSt.AddField(ST:STATECODE,BrowseSt.Q.ST:STATECODE) !set column to browse**

** BrowseSt.AddField(ST:STATENAME,BrowseSt.Q.ST:STATENAME) !set column to browse**

** BrowseSt.InsertControl=?Insert          !set the control to add records**

** BrowseSt.ChangeControl=?Change          !set the control to change records**

** BrowseSt.DeleteControl=?Delete          !set the control to delete records**

** SELF.SetAlerts()                        !alert any keys for ThisWindow**

** RETURN ReturnValue**

**ThisWindow.Kill  PROCEDURE()             !shut down things**

**ReturnValue    BYTE,AUTO**

** CODE**

** ReturnValue = PARENT.Kill()             !call base class shut down**

** IF ReturnValue THEN RETURN ReturnValue.**

** Relate:State.Close                 !close State and related files**

** Relate:State.Kill                  !shut down Relate:State object**

** GlobalErrors.Kill                  !shut down GlobalErrors object**

** RETURN ReturnValue**

**Access:State.Init PROCEDURE**

** CODE**

** PARENT.Init(State,GlobalErrors)**

** SELF.FileNameValue = 'State'**

** SELF.Buffer &= ST:Record**

** SELF.AddKey(ST:StateCodeKey,'ST:StateCodeKey',0)**

**Relate:State.Init PROCEDURE**

** CODE**

** Access:State.Init**

** PARENT.Init(Access:State,1)**