Изменить экранный курсор без необходимости возвращать предыдущий

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Изменить экранный курсор без необходимости возвращать предыдущий[править | править код]

// By implementing Interface we can set the cursor without restore it in the end.
// Example: In convensional way...
var
  Cur: TCursor;
begin
  Cur := Screen.Cursor;
  Screen.Cursor := crSQLWait;
  // do coding here
  // What happend is that if your code did not finish, the screen cursor will
  // remain as crSQLWait.. even with try..finally block (sometimes)
  Screen.Cursor := Cur;
end;

// By using interface, we can implement as follows
type
  ImyCursor = interface
    [(GUID - Ctrl - Shift - G)]
  end;

  TmyCursor = class(TInterfacedObjects, ImyCursor);
  private
    FCursor: TCursor;
  public
    constructor Create;
    destructor Destroy; override;
  end;

implementation

TmyCursor.Create;
begin
  FCursor := Screen.Cursor;
end;

TmyCursor.Destroy;
begin
  Screen.Cursor := FCursor;
  inherited;
end;

var
  C: ImyCursor;
begin
  C := TmyCursor.Create;
  Screen.Curosr := crSQLWait; // whatever cursor you like
  // Do coding here without worring to free it.
  // Screen Cursor will restore when the TMyCursor object get out of scope.
end;


Source: http://delphiworld.narod.ru/
ID: 02334