允许和禁止在圆形滑块

Question

我正在使用 EVARoundSlider ，它具有带有起点和终点的滑块弧。这使得用户可以顺时针和逆时针旋转滑块。

在 touchesMoved 方法中，我可以在滑块视图中获得第一个角度，最后一个角度和当前角度位置。我希望用户在终点处理程序停止，当它达到360度并且启动点处理程序达到0度时。

// Working Code on circular Slider View
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
    UITouch *touch = [touches anyObject];
    CGPoint location = [touch locationInView:self];

    CGFloat fAngle = [self handleAngleByIndex:0];
    CGFloat lAngle = [self handleAngleByIndex:1];
    int a = AngleFromNorth(_centerPoint, location, SLIDER_FLIPPED);

    NSLog(@"First_Angle :%.02f",fAngle);
    NSLog(@"last_Angle :%.02f",lAngle);
    NSLog(@"Current_Angle :%d",a);

    [super touchesMoved:touches withEvent:event];

    _dragging = NO;

    if (!self.isDragging)
    {
        if ([self.delegate respondsToSelector:@selector(sliderDraggin:)])
        {
            [self.delegate sliderDraggin:self];
        }
        //return;
    }

    if ([self.delegate respondsToSelector:@selector(sliderDraggin:)])
    {
        [self.delegate sliderDraggin:self];
    }

    NSUInteger nearestHandleIndex = [self indexOfNearesPointForTouch:touch];
    _nearesHandle = (nearestHandleIndex != NSNotFound) ? _handles[@(nearestHandleIndex)] : nil;

    CGFloat d = [_math distanceBetweenPoint:_centerPoint andPoint:location];

    CGFloat inOff = _radius - _sliderWidth - _offset.inside;
    CGFloat outOff = _radius + _offset.outside;

    if (d < inOff || d > outOff)
    {
        if (self.isNeedToRevoke)
        {
            _dragging = YES;
            return;
        }
    }

    [self.delegate slider:self touchValue:YES atIndex:nearestHandleIndex];
    dispatch_async(dispatch_get_main_queue(), ^{
        int a = AngleFromNorth(_centerPoint, location, SLIDER_FLIPPED);
        [self moveView:_nearesHandle toAngle:a];
        [self drawArc];
    });
    [self informDelegateAboutHandles];
}

如果我尝试为StartAngle和End Angle设置一些条件。在某一点上。它被绞死了，没有什么可以进一步滑动。