TList¶

Class to manage collections of pointers.

Declaration¶

Source position: classesh.inc line 585

type

  TList = class(TObject, IFPObserved)
  public
    constructor Create;
    destructor Destroy;
    procedure FPOAttachObserver;
    procedure FPODetachObserver;
    procedure FPONotifyObservers;
    procedure AddList;
    function Add : Integer;
    procedure Clear;
    procedure Delete;
    class procedure Error;
    procedure Exchange;
    function Expand : TList;
    function Extract : Pointer;
    function First : Pointer;
    function GetEnumerator : TListEnumerator;
    function Contains : Boolean;
    function IndexOf : Integer;
    procedure Insert;
    function Last : Pointer;
    procedure Move;
    procedure Assign;
    function Remove : 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);
    property Capacity: Integer; {rw}
    property Count: Integer; {rw}
    property Items[Index : Integer]: Pointer; {rw}
    property List: PPointerList; {r}
  end;

Inheritance¶

Implements: IFPObserved

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.

Properties¶

Member	Visibility	Description
Capacity	public	Current capacity (i.e. number of pointers that can be stored) of the list.
Count	public	Current number of pointers in the list.
Items	public	Provides access to the pointers in the list.
List read only	public	Memory array where pointers are stored.

See all Properties

Methods¶

Member	Visibility	Description
Add	public	Adds a new pointer to the list.
AddList	public	Add all pointers from another list.
Assign	public	Copy the contents of other lists.
Clear	public	Clears the pointer list.
Contains	public
Create	public	Class to manage collections of pointers.
Delete	public	Removes a pointer from the list.
Destroy	public	Destroys the list and releases the memory used to store the list elements.
Error	public	Raises an EListError exception.
Exchange	public	Exchanges two pointers in the list.
Expand	public	Increases the capacity of the list if needed.
Extract	public	Remove the first occurrence of a pointer from the list.
First	public	Returns the first non-nil pointer in the list.
FPOAttachObserver	public	Add an observer to the list of observers.
FPODetachObserver	public	Remove an observer from the list of observers.
FPONotifyObservers	public	Notify observers of changes in the list.
GetEnumerator	public	Create an IEnumerator instance.
IndexOf	public	Returns the index of a given pointer.
Insert	public	Inserts a new pointer in the list at a given position.
Last	public	Returns the last non-nil pointer in the list.
Move	public	Moves a pointer from one position in the list to another.
Pack	public	Removes Nil pointers from the list and frees unused memory.
Remove	public	Removes a value from the list.
Sort	public	Sorts the pointers in the list.

See all Methods

Name	Description
TStrings	Class to manage arrays or collections of strings.
TCollection	Base class to manage collections of named objects.