问另一个NSScrollView中的NSScrollView

EN

@interface PGEHorizontalScrollView : NSScrollView {
    BOOL currentScrollIsHorizontal;
}
@end

@implementation PGEHorizontalScrollView
-(void)scrollWheel:(NSEvent *)theEvent {
    /* Ensure that both scrollbars are flashed when the user taps trackpad with two fingers */
    if (theEvent.phase==NSEventPhaseMayBegin) {
        [super scrollWheel:theEvent];
        [[self nextResponder] scrollWheel:theEvent];
        return;
    }
    /* Check the scroll direction only at the beginning of a gesture for modern scrolling devices */
    /* Check every event for legacy scrolling devices */
    if (theEvent.phase == NSEventPhaseBegan || (theEvent.phase==NSEventPhaseNone && theEvent.momentumPhase==NSEventPhaseNone)) {
        currentScrollIsHorizontal = fabs(theEvent.scrollingDeltaX) > fabs(theEvent.scrollingDeltaY);
    }
    if ( currentScrollIsHorizontal ) {
        [super scrollWheel:theEvent];
    } else {
        [[self nextResponder] scrollWheel:theEvent];
    }
}
@end

#import <Cocoa/Cocoa.h>

@interface HorizontalScrollView : NSScrollView

@end

@implementation HorizontalScrollView

- (void)scrollWheel:(NSEvent *)theEvent {
    NSLog(@"%@", theEvent);
    if(theEvent.deltaX !=0)
        [super scrollWheel:theEvent];
    else
        [[self nextResponder] scrollWheel:theEvent];

}
@end

class ECGuidedScrollView: NSScrollView
{
    enum ScrollDirection {
        case vertical
        case horizontal
    }

    private var currentScrollMatches: Bool = false
    private var scrollDirection: ScrollDirection

    init(withDirection direction: ScrollDirection) {
        scrollDirection = direction
        super.init(frame: NSRect.zero)
    }

    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    override func scrollWheel(with event: NSEvent)
    {        
        // Ensure that both scrollbars are flashed when the user taps trackpad with two fingers
        if event.phase == .mayBegin {
            super.scrollWheel(with: event)
            nextResponder?.scrollWheel(with: event)
            return
        }

        /*
         Check the scroll direction only at the beginning of a gesture for modern scrolling devices
         Check every event for legacy scrolling devices
         */

        if event.phase == .began || (event.phase == [] && event.momentumPhase == [])
        {
            switch scrollDirection {
            case .vertical:
                currentScrollMatches = fabs(event.scrollingDeltaY) > fabs(event.scrollingDeltaX)
            case .horizontal:
                currentScrollMatches = fabs(event.scrollingDeltaX) > fabs(event.scrollingDeltaY)
            }
        }

        if currentScrollMatches {
            super.scrollWheel(with: event)
        } else {
            self.nextResponder?.scrollWheel(with: event)
        }
    }
}