iOS UIScrollView與側滑手勢沖突解決

建立一個UIScrollView的分類，實作以下方法

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer {
    
    if ([self panBack:gestureRecognizer]) {
        return YES;
    }
    return NO;
    
}
//location_X可自己定義,其代表的是滑動傳回距左邊的有效長度
- (BOOL)panBack:(UIGestureRecognizer *)gestureRecognizer {
    
    //是滑動傳回距左邊的有效長度
    int location_X =40;
    
    if (gestureRecognizer ==self.panGestureRecognizer) {
        UIPanGestureRecognizer *pan = (UIPanGestureRecognizer *)gestureRecognizer;
        CGPoint point = [pan translationInView:self];
        UIGestureRecognizerState state = gestureRecognizer.state;
        if (UIGestureRecognizerStateBegan == state ||UIGestureRecognizerStatePossible == state) {
            CGPoint location = [gestureRecognizer locationInView:self];
            
            //這是允許每張圖檔都可實作滑動傳回
//            int temp1 = location.x;
//            int temp2 = KScreenW;
//            NSInteger X = temp1 % temp2;
//            if (point.x >0 && X < location_X) {
//                return YES;
//            }
            //下面的是隻允許在第一張時滑動傳回生效
            if (point.x > 0 && location.x < location_X && self.contentOffset.x <= 0) {
                return YES;
            }
        }
    }
    return NO;
    
}

- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer {
    
    if ([self panBack:gestureRecognizer]) {
        return NO;
    }
    return YES;
    
}