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...Change Screen.Cursor without need to restore back?
Autor: KK Gian
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Tip Rating (13):  
     


// 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;

procedure....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;


 

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