question: public boolean nextTile ( ) throws ModelControlException { boolean movedToRow = super . nextTile ( ) ; if ( movedToRow ) { curTile = getTileIndex ( ) ; curCallback = callbacks [ curTile ] ; setDisplayFieldValue ( TXT_INDEX , Integer . toString ( curTile ) ) ; if ( curCallback instanceof HiddenValueCallback ) { setHiddenValueCallbackInfo ( ( HiddenValueCallback ) curCallback ) ; } else if ( curCallback instanceof NameCallback ) { setNameCallbackInfo ( ( NameCallback ) curCallback ) ; } else if ( curCallback instanceof PasswordCallback ) { setPasswordCallbackInfo ( ( PasswordCallback ) curCallback ) ; } else if ( curCallback instanceof ChoiceCallback ) { setChoiceCallbackInfo ( ( ChoiceCallback ) curCallback ) ; } else if ( curCallback instanceof TextOutputCallback ) { setTextOutputCallbackInfo ( ( TextOutputCallback ) curCallback ) ; } else { setDisplayFieldValue ( TXT_PROMPT , "" ) ; setDisplayFieldValue ( TXT_VALUE , "" ) ; setDisplayFieldValue ( TXT_INFO , "" ) ; setDisplayFieldValue ( SCRIPT_CONTENT , "" ) ; setDisplayFieldValue ( TEXT_CONTENT , "" ) ; setDisplayFieldValue ( MESSAGE_TYPE , "" ) ; CallBackChoiceTiledView tView = ( CallBackChoiceTiledView ) getChild ( TILED_CHOICE ) ; tView . setChoices ( curTile , null , 0 ) ; } } return movedToRow ; }
target:  moves the current tile position to the next available tile.