滑动手势不起作用
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【中文标题】滑动手势不起作用【英文标题】:Swipe Gesture Not Working 【发布时间】:2013-05-15 09:02:02 【问题描述】:我想滑动我的图像视图,但没有切换到左侧。 我从前卡数组中获取图像。我想在 imageview 中显示并垂直滑动。
我试过这个
FrontsCards =[[NSMutableArray alloc]initWithCapacity:9];
[FrontsCards insertObject:@"cloub1.png" atIndex:0];
[FrontsCards insertObject:@"cloub2.png" atIndex:1];
[FrontsCards insertObject:@"cloub3.png" atIndex:2];
[FrontsCards insertObject:@"cloub4.png" atIndex:3];
[FrontsCards insertObject:@"cloub5.png" atIndex:4];
[FrontsCards insertObject:@"cloub6.png" atIndex:5];
[FrontsCards insertObject:@"cloub7.png" atIndex:6];
[FrontsCards insertObject:@"cloub8.png" atIndex:7];
[FrontsCards insertObject:@"cloub9.png" atIndex:8];
- (void)viewDidLoad
[super viewDidLoad];
UISwipeGestureRecognizer *leftRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(leftSwipeHandle:)];
leftRecognizer.direction = UISwipeGestureRecognizerDirectionLeft;
[leftRecognizer setNumberOfTouchesRequired:1];
[ImgView addGestureRecognizer:leftRecognizer];
- (void)leftSwipeHandle:(UISwipeGestureRecognizer*)gestureRecognizer
int m = 0;
NSLog(@"Left Swipe");
AppDelegate * delegate=(AppDelegate *)[[UIApplication sharedApplication]delegate];
NSLog(@"%d",m);
for(m=0; m<[delegate.FrontsCards count];m++)
int randIdx=arc4random()%[delegate.FrontsCards count]; // Randomly shufffled
ImgView.userInteractionEnabled=YES;
ImgView.image=[UIImage imageNamed:[delegate.FrontsCards objectAtIndex:randIdx]];
NSLog(@"%d",m);
图像未交换到 imageview。 如何解决我的问题帮助我解决这个问题。 提前致谢。
【问题讨论】:
控制台是否显示来自 leftSwipeHandle: 方法的日志? 是否调用了leftSwipeHandle
方法,你检查断点了吗
UIImageView 默认禁用 userInteraction,你需要明确设置为 YES。
我做了所有这些事情,但图像不会显示。并调用了我的 leftSwipeHandle 方法。
@JitendraDeore :leftSwipeHandle
中的 for 循环有什么用。数组中有 9 个元素,并且您使用随机数作为图像,因此最后一张图像将显示在图像视图中。所以我认为不需要那个 for 循环。
【参考方案1】:
尝试使用这个。因为默认图像的用户交互是NO
。所以需要设置用户交互YES
。
FrontsCards =[[NSMutableArray alloc]initWithCapacity:9];
[FrontsCards insertObject:@"cloub1.png" atIndex:0];
[FrontsCards insertObject:@"cloub2.png" atIndex:1];
[FrontsCards insertObject:@"cloub3.png" atIndex:2];
[FrontsCards insertObject:@"cloub4.png" atIndex:3];
[FrontsCards insertObject:@"cloub5.png" atIndex:4];
[FrontsCards insertObject:@"cloub6.png" atIndex:5];
[FrontsCards insertObject:@"cloub7.png" atIndex:6];
[FrontsCards insertObject:@"cloub8.png" atIndex:7];
[FrontsCards insertObject:@"cloub9.png" atIndex:8];
- (void)viewDidLoad
[super viewDidLoad];
UISwipeGestureRecognizer *leftRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(leftSwipeHandle:)];
leftRecognizer.direction = UISwipeGestureRecognizerDirectionLeft;
[leftRecognizer setNumberOfTouchesRequired:1];
[ImgView addGestureRecognizer:leftRecognizer];
// --------------- Add this line here ------------
ImgView.userInteractionEnabled = YES;
- (void)leftSwipeHandle:(UISwipeGestureRecognizer*)gestureRecognizer
int m = 0;
NSLog(@"Left Swipe");
AppDelegate * delegate=(AppDelegate *)[[UIApplication sharedApplication]delegate];
NSLog(@"%d",m);
for(m=0; m<[delegate.FrontsCards count];m++)
int randIdx=arc4random()%[delegate.FrontsCards count]; // Randomly shufffled
ImgView.image=[UIImage imageNamed:[delegate.FrontsCards objectAtIndex:randIdx]];
NSLog(@"%d",m);
【讨论】:
ImgView.userInteractionEnabled = YES;在 viewDidLoad 中写入这一行而不是在这个方法中 - (void)leftSwipeHandle:(UISwipeGestureRecognizer*)gestureRecognizer。并查看我编辑的答案 图像左交换时不显示。 签入for循环。你得到什么图像名称? 不,我的意思是你从这行得到的 [delegate.FrontsCards objectAtIndex:randIdx] 图片显示在nslog但imageview只显示一张图片不刷新图片【参考方案2】:在 .h 文件中
int imgCount;
在 .m 文件中
- (void)viewDidLoad
[super viewDidLoad];
ImgView.userInteractionEnabled=YES;
UISwipeGestureRecognizer *leftRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(leftSwipeHandle:)];
leftRecognizer.direction = UISwipeGestureRecognizerDirectionLeft;
[leftRecognizer setNumberOfTouchesRequired:1];
[ImgView addGestureRecognizer:leftRecognizer];
imgCount = 0;
- (void)leftSwipeHandle:(UISwipeGestureRecognizer*)gestureRecognizer
AppDelegate * delegate=(AppDelegate *)[[UIApplication sharedApplication]delegate];
ImgView.image=[UIImage imageNamed:[delegate.FrontsCards objectAtIndex:imgCount]];
imgCount++;
if (imgCount >= 9)
imgCount = 0;
【讨论】:
答案的第一部分可能是有效的,但是使用imgCount是无效的,它消除了随机性。 是的,但不需要在问题中提到的 leftSwipeHandle 方法中编写 for 循环。所以,我写了这段代码......如果这是可行的,那么我修改一些代码......这是为了检查图像是否改变...... cloub1.png, cloub2.png 所有图片是否存在于资源中? 所有图片都在资源中。 NSLog(@"%@",[delegate.FrontsCards objectAtIndex:imgCount]);你能给出这条线的输出吗?【参考方案3】:试试这个
[ImgView addGestureRecognizer:leftRecognizer];
//Add this
ImgView.userInteractionEnabled = YES;
【讨论】:
【参考方案4】:你需要在UIImageView
上设置imageview.userInteractionEnabled = YES;
。
【讨论】:
打印图片名称 [delegate.FrontsCards objectAtIndex:randIdx] 是正确的还是空白的? 打印什么?..[delegate.FrontsCards objectAtIndex:randIdx]【参考方案5】:试试这个。
UISwipeGestureRecognizer *leftRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(leftSwipeHandle:)];
leftRecognizer.direction = UISwipeGestureRecognizerDirectionLeft;
[leftRecognizer setNumberOfTouchesRequired:1];
[ImgView addGestureRecognizer:leftRecognizer];
ImgView.userInteractionEnabled = YES;
UIImageView
默认禁用。您需要启用它。
【讨论】:
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