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The LIST control places a scrolling list of data items on the WINDOW, TOOLBAR, or REPORT at the position and size specified by its AT attribute. It is valid in Clarion Win32 Windows, and also for REPORT structures in both Clarion Win32 and Clarion#. The data items displayed in the LIST come from a QUEUE or STRING specified by the FROM attribute and are formatted by the parameters specified in the FORMAT attribute (which can include colors, icons, and tree control parameters).

The CHOICE procedure returns the QUEUE entry number (the value returned by POINTER(queue)) of the selected item when the EVENT:Accepted event has been generated by the LIST. The data displayed in the LIST is automatically refreshed every time through the ACCEPT loop, whether the AUTO attribute is present or not.

A LIST with the DROP attribute displays only the currently selected data item on screen until the control has focus and the user presses the down arrow key, or CLICKS ON the the icon to the right of the displayed data item. When either of these occurs, the selection list appears (“drops down”) to allow the user to select an item.

A LIST with the IMM attribute generates an event every time the user moves the highlight bar to another selection, or presses any key (all keys are implicitly ALRTed). This allows an opportunity for the source code to re-fill the display QUEUE, or get the currently highlighted record to display other fields from the record. If VSCROLL is also present, the vertical scroll bar is always displayed and when the end-user CLICKS on the scroll bar, events are generated but the list does not move (executable code should perform this action). You can interrogate the PROP:VscrollPos property to determine the scroll thumb's position from 0 (top) to 255 (bottom).

A LIST with the VCR attribute has scroll control buttons like a Video Cassette Recorder to the left of the horizontal scroll bar (if there is one). These buttons allow the user to use the mouse to scroll through the list.

A LIST with the DRAGID attribute can serve as a drag-and-drop host, providing information to be moved or copied to another control. A LIST with the DROPID attribute can serve as a drag-and-drop target, receiving information from another control. These attributes work together to specify drag-and-drop “signatures” that define a valid target for the operation. The DRAGID() and DROPID() procedures, along with the SETDROPID procedure, are used to perform the data exchange.

REPORT Usage

LIST is valid only in a DETAIL structure. Its purpose is to allow the report format to duplicate the screen appearance of the LIST's FORMAT setting. When the first instance of the DETAIL structure containing the LIST prints, any headers in the FORMAT attribute print along with the current FROM attribute entry. When the last DETAIL structure containing the LIST prints, the LIST footers print along with the current FROM attribute entry.

Events Generated:

Example:

Q    QUEUE
F1    STRING(1)
F2    STRING(4)
    END 
 
MDIChild WINDOW('Child One'),AT(0,0,320,200),MDI,MAX,HVSCROLL
         LIST,AT(0,0,20,20),USE(?L1),FROM(Que),IMM
         LIST,AT(20,0,20,20),USE(?L2),FROM(Que),KEY(F10Key)
         LIST,AT(40,0,20,20),USE(?L3),FROM(Que),MSG('Button 3')
         LIST,AT(60,0,20,20),USE(?L4),FROM(Que),HLP('Check4Help')
         LIST,AT(80,0,20,20),USE(?L5),FROM(Q),FORMAT('5C~List~15L~Box~'),COLUMN
         LIST,AT(100,0,20,20),USE(?L6),FROM(Que),FONT('Arial',12)
         LIST,AT(120,0,20,20),USE(?L7),FROM(Que),DROP(6)
         LIST,AT(140,0,20,20),USE(?L8),FROM(Que),HVSCROLL,VCR
         LIST,AT(180,0,20,20),USE(?L10),FROM(Que),CURSOR(CURSOR:Wait)
         LIST,AT(200,0,20,20),USE(?L11),FROM(Que),ALRT(F10Key)
         LIST,AT(220,0,20,20),USE(?L12),FROM(Que),LEFT
         LIST,AT(240,0,20,20),USE(?L13),FROM(Que),RIGHT
         LIST,AT(260,0,20,20),USE(?L14),FROM(Que),CENTER
         LIST,AT(280,0,20,20),USE(?L15),FROM(Que),VSCROLL,VCR
         LIST,AT(300,0,20,20),USE(?L16),FROM('Apples|Peaches|Pumpkin|Pie')
         LIST,AT(320,0,20,20),USE(?L17),FROM('TBA')
        END
 
 
CustRpt   REPORT,AT(1000,1000,6500,9000),THOUS
CustDetail DETAIL,AT(0,0,6500,1000)
           LIST,AT(80,0,20,20),USE(?L1),FROM(Q),FORMAT('5C~List~15L~Box~') 
          END
         END
   CODE
   OPEN(MDIChild)
    ?L1{PROP:From} = 'Live|Long|And|Prosper'   !Runtime FROM attribute assignment

See Also:

COMBO

DRAGID

DROPID

SETDROPID

FORMAT (Runtime Properties)

FORMAT (Style Properties)

FORMAT (Other Properties)

FORMAT (Mouse Click Properties)

FROM (LIST data sources)

PROPLIST (list of all properties available to be set at runtime)