drag object vertically

i like to drag this object vertically instead of horizontally, which is doin it now:

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
    UITouch *touch = [[event allTouches] anyObject];
    CGPoint location = [touch locationInView:touch.view];
  开发者_运维技巧  if (CGRectContainsPoint(myObject.frame, location)){
    CGPoint xLocation = CGPointMake(location.x, myObject.center.y);
    myObject.center = xLocation;
    }
}

CGPoint yLocation = CGPointMake(myObject.center.x, location.y);
myObject.center = yLocation;