TList

[Properties (by Name)][Methods (by Name)][Events (by Name)]

Class to manage collections of pointers.

Declaration

Source position: classesh.inc line 296

Type
  TList = class (TObject, IFPObserved)
  private
    FList : TFPList;
    FObservers : TFPList;
    procedure CopyMove(aList: TList);
    procedure MergeMove(aList: TList);
    procedure DoCopy(ListA: TList; ListB: TList);
    procedure DoSrcUnique(ListA: TList; ListB: TList);
    procedure DoAnd(ListA: TList; ListB: TList);
    procedure DoDestUnique(ListA: TList; ListB: TList);
    procedure DoOr(ListA: TList; ListB: TList);
    procedure DoXOr(ListA: TList; ListB: TList);
  protected
    function Get(Index: Integer) : Pointer;
    procedure Grow;  Virtual;
    procedure Put(Index: Integer; Item: Pointer);
    procedure Notify(Ptr: Pointer; Action: TListNotification);  Virtual;
    procedure SetCapacity(NewCapacity: Integer);
    function GetCapacity : Integer;
    procedure SetCount(NewCount: Integer);
    function GetCount : Integer;
    function GetList : PPointerList;
  public
    constructor Create;
    destructor Destroy;  Override;
    procedure FPOAttachObserver(AObserver: TObject);
    procedure FPODetachObserver(AObserver: TObject);
    procedure FPONotifyObservers(ASender: TObject; 
                                AOperation: TFPObservedOperation; 
                                Data: Pointer);
    procedure AddList(AList: TList);
    function Add(Item: Pointer) : Integer;
    procedure Clear;  Virtual;
    procedure Delete(Index: Integer);
    class procedure Error(const Msg: string; Data: PtrInt);  Virtual;
    procedure Exchange(Index1: Integer; Index2: Integer);
    function Expand : TList;
    function Extract(item: Pointer) : Pointer;
    function First : Pointer;
    function GetEnumerator : TListEnumerator;
    function IndexOf(Item: Pointer) : Integer;
    procedure Insert(Index: Integer; Item: Pointer);
    function Last : Pointer;
    procedure Move(CurIndex: Integer; NewIndex: Integer);
    procedure Assign(ListA: TList; AOperator: TListAssignOp; ListB: TList);
    function Remove(Item: Pointer) : Integer;
    procedure Pack;
    procedure Sort(Compare: TListSortCompare);
    procedure Sort(Compare: TListSortCompare; 
                  SortingAlgorithm: PSortingAlgorithm);
    procedure Sort(Compare: TListSortComparer_Context; Context: Pointer);
    procedure Sort(Compare: TListSortComparer_Context; Context: Pointer; 
                  SortingAlgorithm: PSortingAlgorithm);
    Capacity : Integer;
    Count : Integer;
    Items[Index: Integer]: Pointer; default;
    List : PPointerList;
  end
  ;

Description

TList is a class that can be used to manage collections of pointers. It introduces methods and properties to store the pointers, search in the list of pointers, sort them. It manages its memory by itself, no intervention for that is needed. It has an event notification mechanism which allows to notify of list changes. This slows down some of TList mechanisms, and if no notification is used, TFPList may be used instead.

To manage collections of strings, it is better to use a TStrings descendant such as TStringList . To manage general objects, a TCollection class exists, from which a descendant can be made to manage collections of various kinds.

Members

Member Type Visibility Description
Add Method public Adds a new pointer to the list.
AddList Method public Add all pointers from another list
Assign Method public Copy the contents of other lists.
Capacity Property public Current capacity (i.e. number of pointers that can be stored) of the list.
Clear Method public Clears the pointer list.
CopyMove Method private
Count Property public Current number of pointers in the list.
Create Method public Class to manage collections of pointers.
Delete Method public Removes a pointer from the list.
Destroy Method public Destroys the list and releases the memory used to store the list elements.
DoAnd Method private
DoCopy Method private
DoDestUnique Method private
DoOr Method private
DoSrcUnique Method private
DoXOr Method private
Error Method public Raises an EListError exception.
Exchange Method public Exchanges two pointers in the list.
Expand Method public Increases the capacity of the list if needed.
Extract Method public Remove the first occurrence of a pointer from the list.
First Method public Returns the first non-nil pointer in the list.
FList Field private
FObservers Field private
FPOAttachObserver Method public Add an observer to the list of observers
FPODetachObserver Method public Remove an observer from the list of observers
FPONotifyObservers Method public Notify observers of changes in the list
Get Method protected
GetCapacity Method protected
GetCount Method protected
GetEnumerator Method public Create an IEnumerator instance
GetList Method protected
Grow Method protected
IndexOf Method public Returns the index of a given pointer.
Insert Method public Inserts a new pointer in the list at a given position.
Items Property public Provides access to the pointers in the list.
Last Method public Returns the last non-nil pointer in the list.
List Property public Memory array where pointers are stored.
MergeMove Method private
Move Method public Moves a pointer from one position in the list to another.
Notify Method protected
Pack Method public Removes Nil pointers from the list and frees unused memory.
Put Method protected
Remove Method public Removes a value from the list.
SetCapacity Method protected
SetCount Method protected
Sort Method public Sorts the pointers in the list.

Inheritance

Class Description
TList(IFPObserved) Class to manage collections of pointers.

See also

Name Description
Integer A signed 16-bits integer
Integer A signed 16-bits integer
TCollection Base class to manage collections of named objects.
TFPList Class to manage collections of pointers.
TFPList Class to manage collections of pointers.
TStrings Class to manage arrays or collections of strings