我正在尝试使用动画蒙版制作圆形蒙版图像视图,并使用不同的解决方案。下面的示例完成了这项工作,但我遇到了两个问题:
1)为什么我不能使图像可点击?添加例如。一个UITapGestureRecognizer
不起作用。我的猜测是,掩码会阻止触摸操作传播到视图层次结构中的较低级别。
2)动画蒙版运行非常快,我无法使用UIView
块动画调整持续时间
我该如何解决这些?
- (void) addCircle {
// this is the encapsulating view
//
base = [[UIView alloc] init];
//
// this is the button background
//
base_bgr = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"c1_bgr.png"]];
base_bgr.center = CGPointMake(60, 140);
[base addSubview:base_bgr];
//
// icon image
//
base_icon = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"c1_ico.png"]];
base_icon.center = CGPointMake(186*0.3/2, 182*0.3/2);
base_icon.transform = CGAffineTransformMakeScale(0.3, 0.3);
[base addSubview:base_icon];
//
// the drawn circle mask layer
//
circleLayer = [CAShapeLayer layer];
// Give the layer the same bounds as your image view
[circleLayer setBounds:CGRectMake(0.0f, 0.0f, [base_icon frame].size.width,
[base_icon frame].size.height)];
// Position the circle
[circleLayer setPosition:CGPointMake(186*0.3/2-7, 182*0.3/2-10)];
// Create a circle path.
UIBezierPath *path = [UIBezierPath bezierPathWithOvalInRect:
CGRectMake(0.0f, 0.0f, 70.0f, 70.0f)];
// Set the path on the layer
[circleLayer setPath:[path CGPath]];
[[base layer] setMask:circleLayer];
[self.view addSubview:base];
base.center = CGPointMake(100, 100);
base.userInteractionEnabled = YES;
base_bgr.userInteractionEnabled = YES;
base_icon.userInteractionEnabled = YES;
//
// NOT working: UITapGestureRecognizer
//
UITapGestureRecognizer *tapgesture = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapit:)];
[base_icon addGestureRecognizer:tapgesture];
//
// BAD but WORKS :) properly positioned UIButton over the masked image
//
base_btn = [UIButton buttonWithType:UIButtonTypeCustom];
base_btn.frame = CGRectMake(base.frame.origin.x, base.frame.origin.y, base_icon.frame.size.width, base_icon.frame.size.height);
[base_btn addTarget:self action:@selector(tapit:) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:base_btn];
}
这是点击处理程序,这是蒙版动画。无论我尝试的持续时间是多少,它的动画速度都很快 - 大约 0.25 秒,我无法调整它。
- (void) tapit:(id) sender {
//...
[UIView animateWithDuration:1.0
delay:0.0
options:UIViewAnimationOptionCurveEaseOut
animations:^ {
[circleLayer setTransform:CATransform3DMakeScale(10.0, 10.0, 1.0)];
}
completion:^(BOOL finished) {
// it is not necessary if I manage to make the icon image tappable
base_btn.frame = [base convertRect:base_icon.frame toView:self.view];
}];
}
}