Question

我正试图一个接一个地连接两个手势。 UILongPressGestureRecognizer，然后是UIPanGestureRecognizer。

我想检测长按，然后允许识别平移手势。

我已经将UIPanGestureRecognizer转包并添加了一个panEnabled Bool iVar。在initWith框架中，我将panEnabled设置为NO。

在触摸中移动我检查它是否已启用，然后调用Super touchesMoved（如果已启用）。

在我的LongPress手势处理程序中，我循环查看手势，直到找到我的Subclassed Gesture，然后setPanEnabled为YES。

它似乎正在工作，虽然它像原始的平移手势识别器不能正常工作而没有设置正确的状态。我知道如果你对UIGestureRecognizer进行Subclass，你需要自己维护状态，但我认为如果你是UIPanGestureRecognizer的子类，并且对于调用super的所有触摸方法，它将在那里设置状态。

这是我的子类.h文件

#import <UIKit/UIKit.h>
#import <UIKit/UIGestureRecognizerSubclass.h>

@interface IoUISEListPanGestureRecognizer : UIPanGestureRecognizer {
    int IoUISEdebug;
    BOOL panEnabled;    
}
- (id)initWithTarget:(id)target action:(SEL)action;
@property(nonatomic, assign) int IoUISEdebug;
@property(nonatomic, assign) BOOL panEnabled;

@end

这是子类.m文件

#import "IoUISEListPanGestureRecognizer.h"

@implementation IoUISEListPanGestureRecognizer
@synthesize IoUISEdebug;
@synthesize panEnabled;

- (id)initWithTarget:(id)target action:(SEL)action {
    [super initWithTarget:target action:action];
    panEnabled = NO;
    return self;
}

- (void)ignoreTouch:(UITouch*)touch forEvent:(UIEvent*)event {
    [super ignoreTouch:touch forEvent:event];
}

-(void)reset {
    [super reset];
    panEnabled = NO;
}

- (BOOL)canPreventGestureRecognizer:(UIGestureRecognizer *)preventedGestureRecognizer {  
    return [super canPreventGestureRecognizer:preventedGestureRecognizer];
}

- (BOOL)canBePreventedByGestureRecognizer:(UIGestureRecognizer *)preventingGestureRecognizer{
    return [super canBePreventedByGestureRecognizer:preventingGestureRecognizer];
}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
    [super touchesBegan:touches withEvent:event];
}

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{
    if (panEnabled) {
        [super touchesMoved:touches withEvent:event];
    }
}

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
    [super touchesEnded:touches withEvent:event];    
}

- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event{
    [super touchesCancelled:touches withEvent:event];
}
@end

Answer 1

如果您创建一个名为canPan的BOOL并包含以下委托方法，则可以将标准UILongPressGestureRecognizer和UIPanGestureRecognizer连接到同一视图。在识别长按手势时调用的选择器 - 将canPan更改为YES。您可能希望在识别后禁用长按，并在平移完成后重新启用它。 - 不要忘记在手势识别器上分配代理属性。

- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer{
    if (!canPan && [gestureRecognizer isKindOfClass:[UIPanGestureRecognizer class]]) {
      return NO;
    }

    return YES;
}

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer{
  return YES;
}

将UIPanGestureRecognizer子类化以在识别之前等待条件

1 个答案: