我有一个UIImageView它有一个动画UIImage。UIImageView本身使用CAKeyframeAnimation和CGMutablePathRef来提供路径中的一些随机性。我的问题是,我需要跟踪当有人点击动画UIIMageView。
我已经在这上面打了我的头一段时间了,似乎我应该比较一个UITouch和UIImage的呈现层在屏幕上的位置,但我不知道如何获得它的坐标。
主要问题是,我如何获得在屏幕上动画的UIIMageView的坐标并将它与点击发生的地方进行比较?
如果我现在运行代码,它会抛出一个错误:
-[CALayer center]:无法识别的选择器发送到实例0xa105150
它不再崩溃,但我仍然在如何确定的UIImageView的位置,因为它在屏幕上移动。
我的相关代码如下。如有任何帮助,我将不胜感激。
- (void)animateCarrierFish
{
NSInteger getWhichFish = (arc4random()%[self.fishes count]);
NSArray *selectedFish = [NSArray arrayWithArray:[self.fishes objectAtIndex:getWhichFish]];
UIImage *fishName = [selectedFish objectAtIndex:0];
UIImageView *fishCarrier = [[UIImageView alloc] initWithImage:fishName];
fishCarrier.animationImages = selectedFish;
fishCarrier.animationDuration = 1.5;
fishCarrier.animationRepeatCount = 0;
fishCarrier.frame = CGRectMake(0, 0, fishName.size.width*screenScale, fishName.size.height*screenScale);
NSInteger startPoint;
NSInteger endPoint;
NSInteger oppositeMod;
NSInteger fromWhichDirection = (arc4random()%2);
if(fromWhichDirection==1)
{
startPoint = rightEdge;
endPoint = leftEdge;
oppositeMod = -rightEdge;
fishCarrier.transform = CGAffineTransformMakeScale(-1, 1);
} else {
startPoint = leftEdge;
endPoint = rightEdge;
oppositeMod = 0;
}
NSInteger aniSpeed = [self getRandomNumberBetweenMin:15 andMax:20];
CAKeyframeAnimation *pathAnimation = [CAKeyframeAnimation animationWithKeyPath:@"position"];
pathAnimation.duration = aniSpeed;
pathAnimation.calculationMode = kCAAnimationCubic;
pathAnimation.fillMode = kCAFillModeForwards;
pathAnimation.removedOnCompletion = NO;
CGMutablePathRef pointPath = CGPathCreateMutable();
NSInteger yPoint = [self getRandomNumberBetweenMin:waterLine andMax:seaFloor];
CGPathMoveToPoint(pointPath, NULL, startPoint, yPoint);
NSInteger howManyDips = [self getRandomNumberBetweenMin:2 andMax:4];
int i=0;
for (i = 0; i < howManyDips; i++)
{
yPoint = [self getRandomNumberBetweenMin:waterLine andMax:seaFloor];
NSInteger xMod = [self getRandomNumberBetweenMin:-25 andMax:25];
NSInteger xPoint = (([[UIScreen mainScreen] bounds].size.height/(howManyDips+1))*(i+1)) + xMod + oppositeMod;
if (xPoint <0)
{
xPoint = xPoint*-1;
}
CGPathAddLineToPoint(pointPath, NULL, xPoint, yPoint);
}
yPoint = [self getRandomNumberBetweenMin:waterLine andMax:seaFloor];
CGPathAddLineToPoint(pointPath, NULL, endPoint, yPoint);
pathAnimation.path = pointPath;
CGPathRelease(pointPath);
[fishCarrier.layer addAnimation:pathAnimation forKey:@"pathAnimation"];
[self.view addSubview:fishCarrier];
[fishCarrier startAnimating];
fishCarrier.userInteractionEnabled = YES; // these two lines don't seem to do anything
fishCarrier.multipleTouchEnabled = YES;
fishCarrier.tag=[self.swimmers count];
[self.swimmers addObject:fishCarrier];
}
- (void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
[super touchesBegan:touches withEvent:event];
UITouch *touch = [touches anyObject];
CGPoint touch_point = [touch locationInView:self.view];
for (UIImageView *image in self.swimmers) {
// HOW do I get the coordinates in the main view of this sublayer?
}
}
通过对touchesBegan方法进行以下更改,我终于能够让对象报告它们在屏幕上的位置:
- (void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
[super touchesBegan:touches withEvent:event];
UITouch *touch = [touches anyObject];
CGPoint startPoint = [touch locationInView:self.view];
CGFloat x = startPoint.x;
CGFloat y = startPoint.y;
//create touch point
CGPoint touchPoint = CGPointMake(x, y);
// loop through the items we're iterested in being tapped on here
for (UIImageView *fish in self.swimmers) {
CGRect fishFrame = [[fish.layer presentationLayer] frame];
if (CGRectContainsPoint(fishFrame, touchPoint)) {
NSLog(@"You hit fish: %u",fish.tag); // do stuff here
}
}
}
为什么您期望CALayer
响应center
的消息?如果你读过它的文档,你就会发现它没有实现一个名为center
的方法。如果你想获得图层的几何中心,手动计算:
CGPoint center;
center.x = CGRectGetMidX(layer.bounds);
center.y = CGRectGetMidY(layer.bounds);
编辑:似乎你想要的中心相对于超级层?视图?无论…):
CGPoint center;
center.x = CGRectGetMidX(layer.frame);
center.y = CGRectGetMidY(layer.frame);