SAS/AF Filtered SCL List

Reader Comments

This class was developed to allow sophisticated filtering of listing models such as the Data Set List Model. As such, it can provide filtering on any model that supports the StaticStringList Interface (see sashelp.classes.staticstringlist.intrface)

The class functions as an intermediary between a model and a view, and thus, is a model to a viewer and a (non-visual) viewer of a model. The StaticStringList interface is both supported and required.

This class can be used in a SAS/AF frame by compiling the class definition and implementation and adding the class to the Components tab. To instantiate the class during build, drag the class from the components tab and drop it into a frame. Set a viewer's model attribute to the filteredlist and the filteredlist's model to the model that is being filtered for the viewer.

The class contains these attributes:

Data:
  itemsMatch - a SAS regular expression pattern.
               Only the source list items matching this pattern will be forwarded.

The itemsMatch attribute would typically be linked to a TextEntry.text attribute where the user can type in a pattern.

Installation

This class is designed to be installed as common.utility.filteredlist_c.class

Class definition

This scl code defines the class. Be sure to SAVECLASS it (don't need to compile it since there are no method implementations in the class definition.)
Note that the class both supports and requires the StaticStringList Interface. In order to support StaticStringList a class must implement four methods: _getItem(), getIndex(), _getItems(), _count()

common.utility.filteredlist_cclass.scl

Class COMMON.UTILITY.FILTEREDLIST_C.CLASS
      Extends SASHELP.FSP.OBJECT
      Supports SASHELP.CLASSES.STATICSTRINGLIST.INTRFACE
      Requires SASHELP.CLASSES.STATICSTRINGLIST.INTRFACE
      / ( Description="Filtered List")  ;

   /*--------------------------*/
   /* Attributes:              */
   /*--------------------------*/

   Public  Char description
      / (State="O",
         InitialValue="Filtered List")
      ;

   Public  Char itemsMatch
      / (SetCAM="setcamItemsMatch",
         Category="Data",
         Description="Regular expression items must match to pass through")
      ;

   Public  List items
      / (Editor="sashelp.classes.SimpleListEditor.frame",
         Category="Data")
      ;

   Public  Char contentsUpdatedAttributes
      / (State="O",
         InitialValue="triggerViewerUpdate")
      ;

   Public  Num triggerViewerUpdate
      / (InitialValue=0,
         Category="Model/View")
      ;

   /*--------------------------*/
   /* Methods:                 */
   /*--------------------------*/

   _getItem: Public Method
     index:Input:Num
     Return=Char
    / (SCL="common.utility.filteredlist_c.scl",
        Label="getItem",
        ArgDesc1="specifies the index number of the item to retrieve on the items list",
        ReturnDesc="returns the text of the specified list item index")
      ;

   _getIndex: Public Method
     text:Input:Char
     Return=Num
    / (SCL="common.utility.filteredlist_c.scl",
        Label="getIndex",
        ArgDesc1="specifies the text to search for on the items list",
        ReturnDesc="returns the index number of the specified text if found")
      ;

   _getItems: Public Method
     Return=List
    / (SCL="common.utility.filteredlist_c.scl",
        Label="getItems")
      ;

   _count: Public Method
     Return=Num
    / (SCL="common.utility.filteredlist_c.scl",
        Label="count")
      ;

   _onContentsUpdated: Public Method
     attributeName:Input:Char
    / (SCL="common.utility.filteredlist_c.scl",
        Label="onContentsUpdated",
        State="O",
        ArgDesc1="Name of attribute whose value changed to cause the event")
      ;

   _setcamModel: Public Method
     attributeValue:Update:Char
     RETURN=Num
    / (SCL="common.utility.filteredlist_c.scl",
        Label="setcamModel",
        State="O",
        ArgDesc1="contains the attribute value",
        ReturnDesc="returns 0 if successful,  >0 if error, <0 if warning")
      ;

   filterModelData: Public Method
     regexp:Input:Char
    / (SCL="common.utility.filteredlist_c.scl")
      ;

   setcamItemsMatch: Protected Method
     attributeValue:Update:Char
     RETURN=Num
    / (SCL="common.utility.filteredlist_c.scl",
        Description="Invoked when the itemsMatch attribute is changed",
        ArgDesc1="contains the attribute value",
        ReturnDesc="returns 0 if successful, >0 if error, <0 if warning")
      ;

EndClass  ;

Class implementation

Place this code in common.utility.filteredlist_c.scl, issue commands COMPILE, and END.

useclass common.utility.FilteredList_c.class;

count: public method
  return=num;

  return listlen (items);
endmethod;

getIndex: public method
  item:input:char
  return=num;

  return searchc (items, item);
endmethod;

getItem: public method
  index:input:num
  return=char;

  return getitemC (items, index);
endmethod;

* this method is invoked by viewer using this class as a model;
getItems: public method
  return=list;

  return(items);
endmethod;

onContentsUpdated: public method
  content:input:char;

  filterModelData(itemsMatch);
  triggerViewerUpdate = datetime();
endmethod;

setcamModel: protected method
  av:update:char
  return=num;

  _super(av);
  if av = ' ' then return 0;

  filterModelData(itemsMatch);
  triggerViewerUpdate = datetime();
endmethod;

filterModelData: public method
  regexp:input:char;

  declare num rc rx i ;

  if modelid < 1 then return;

  rc = clearlist (items);

  * use method defined for StaticStringList interface to get the models list of items;
  * do not presume the model class has list of items in an attribute named .items;

  declare list modelItems = modelid._getItems();

  if regexp ne ' ' then do;
    rx = rxparse(regexp);
    if rx > 0 then do;
      do i = 1 to listlen (modelItems) ;
        declare char item = getitemC (modelItems, i);
        if rxmatch (rx, item) then
          rc = insertC (items, item, -1);
      end;
      call rxfree (rx);
    end;
  end;
  else
    rc = copylist (modelItems, 'N', items);
endmethod;


setcamItemsMatch: protected method
  av:update:char
  return=num;

  filterModelData(av);
  triggerViewerUpdate = datetime();
endmethod;

enduseclass;