如何修复从另一个 class 调用时处理 PanGestureRecognizer 的错误？

Question

我想将 PanGestureRecognizer 添加到 UIViewController 的 UIView。我将视图分成九个相等的部分，并按它们创建一个 UIViews。我还在每个部分添加了 PanGestureRocgnizer。当我在另一个 class 需要它的地方调用它时，它工作正常但是当我触摸屏幕的某些部分以启动 PangestureRecognizer 的句柄方法时，我收到错误：[UIView handlePanGestureRocognizer:]：发送到实例 0x17de2ee0 的无法识别的选择器。这是我的代码：

#import "CustomGestureRecognizer.h"

@implementation CustomGestureRecognizer
@synthesize arrayOfPatternsForComparison;
@synthesize arrayOfSubviews;
@synthesize arrayOfPanGestureRecognizers;



- (void)initialize:(UIView *)view {
    arrayOfPatternsForComparison = [[NSMutableArray alloc] init];
    arrayOfSubviews = [[NSMutableArray alloc] init];
    arrayOfPanGestureRecognizers = [[NSMutableArray alloc] init];

    [self createPatternsForComparison];
    [self splitScreenInParts:view];
    [self setPanGestrueRecognizersOnEveryPartOfTheScreen];
}

- (void)createPatternsForComparison {

}

- (void)splitScreenInParts:(UIView *)view {
    CGSize onePart = CGSizeMake(view.frame.size.width/3, view.frame.size.height/3);
    CGFloat x_positionOfPart = 0;
    CGFloat y_positionOfPart = 0;

    for (NSUInteger j=0; j<3; j++) {
        for (NSUInteger i=0; i<3; i++) {
            UIView *_view = [[UIView alloc] initWithFrame:CGRectMake(x_positionOfPart, y_positionOfPart, onePart.width, onePart.height)];

            [[_view layer] setBorderWidth:1.0];
            [[_view layer] setBorderColor:[UIColor redColor].CGColor];

            x_positionOfPart += onePart.width;
            [arrayOfSubviews addObject:_view];
            [view addSubview:_view];
        }
        y_positionOfPart += onePart.height;
        x_positionOfPart = 0;
    }

}

- (void)setPanGestrueRecognizersOnEveryPartOfTheScreen {
    for (UIView *view in arrayOfSubviews) {
        UIPanGestureRecognizer *panGestureRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:view action:@selector(handlePanGestureRocognizer:)];
        [[panGestureRecognizer view] setTag:[arrayOfSubviews indexOfObject:view]];
        [view addGestureRecognizer:panGestureRecognizer];
    }
}


- (void)handlePanGestureRocognizer:(UIPanGestureRecognizer *)sender {
    NSLog(@"%d", [[sender view] tag]);
}



@end

在另一个 class 的 UIViewController 中，我这样称呼它：

- (void)viewWillAppear:(BOOL)animated {
    CustomGestureRecognizer *cgr = [[CustomGestureRecognizer alloc] init];
    [cgr initialize:[self view]];
}

如何解决这个问题？感谢您的回答。

Answer 1

因为cgr调用的时候就释放了

您必须在 .h 中创建一个变量 CustomGestureRecognizer *cgr 然后：

- (void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];
    cgr = [[CustomGestureRecognizer alloc] init];
    [cgr initialize:[self view]];
}

然后改变这一行

UIPanGestureRecognizer *panGestureRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:view action:@selector(handlePanGestureRocognizer:)];

到

UIPanGestureRecognizer *panGestureRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(handlePanGestureRocognizer:)];

Answer 2

这一行有问题。

UIPanGestureRecognizer *panGestureRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:view action:@selector(handlePanGestureRocognizer:)];

在这里您将目标作为 "view" 传递，这是一个子视图。目标应该是 viewController 对象，例如 "self" 或任何其他 viewController 对象。

而且在这里您只是创建了 9 个视图（我认为是在 NSObject 子类中）并添加到一个数组中，但是这些视图没有作为子视图添加到任何视图中。为此，您可以 return 将该数组添加到您的 viewController，然后向那些以自身为目标的视图添加平移手势。然后它会工作。

Answer 3

我通过在 .h[=21 中添加 var *CustomGestureRecognizer cgr 解决了这个问题=] 另一个 class 就像 anhtu 说的那样并更改

UIPanGestureRecognizer *panGestureRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:view action:@selector(handlePanGestureRocognizer:)];

目标 self 就像 Dev 说的那样。

如何修复从另一个 class 调用时处理 PanGestureRecognizer 的错误？

How to fix error on handling PanGestureRecognizer when called from another class?

iphone

objective-c

uiview

ios