objective c - guide - UIScrollview obteniendo eventos táctiles

ios frameworks

Question

¿Cómo puedo detectar puntos de contacto en mi UIScrollView ? Los métodos delegados toques no están funcionando.

Answer 1

Configurar un reconocedor de gestos táctiles:

UITapGestureRecognizer *singleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(singleTapGestureCaptured:)];
[scrollView addGestureRecognizer:singleTap];    

y obtendrás los toques en:

- (void)singleTapGestureCaptured:(UITapGestureRecognizer *)gesture
{ 
    CGPoint touchPoint=[gesture locationInView:scrollView];
}

Answer 2

Puede crear su propia subclase UIScrollview y luego puede implementar lo siguiente:

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event 

{

NSLog(@"DEBUG: Touches began" );

UITouch *touch = [[event allTouches] anyObject];

    [super touchesBegan:touches withEvent:event];
}

- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event {

    NSLog(@"DEBUG: Touches cancelled");

    // Will be called if something happens - like the phone rings

    UITouch *touch = [[event allTouches] anyObject];

    [super touchesCancelled:touches withEvent:event];

}


- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {

    NSLog(@"DEBUG: Touches moved" );

    UITouch *touch = [[event allTouches] anyObject];

    [super touchesMoved:touches withEvent:event];

}

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
    NSLog(@"DEBUG: Touches ending" );
    //Get all the touches.
    NSSet *allTouches = [event allTouches];

    //Number of touches on the screen
    switch ([allTouches count])
    {
        case 1:
        {
            //Get the first touch.
            UITouch *touch = [[allTouches allObjects] objectAtIndex:0];

            switch([touch tapCount])
            {
                case 1://Single tap

                    break;
                case 2://Double tap.

                    break;
            }
        }
            break;
    }
    [super touchesEnded:touches withEvent:event];
}

Answer 3

Si estamos hablando de los puntos dentro de la vista de desplazamiento, entonces puedes enlazar con el método de delegado:

- (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView

y dentro del método, lea la propiedad:

@property(nonatomic) CGPoint contentOffset

desde scrollView para obtener la coordinación.