5、粒子效果
这个东西就是CAReplicatorLayer（复制图层）和Core Graphics的结合吧，我是采用UIBezierPath来绘制线条，然后将绘制好的path赋值给小球的animation路径，然后将小球添加到复制图层，设置下instanceCount，设置下延迟时间，效果就出来了。
代码：
#import "ZYDrawView.h"
@interface ZYDrawView ()
@property (nonatomic, strong) UIBezierPath *bezierPath;
@property (nonatomic, weak) CAReplicatorLayer *replicatorLayer;
@property (nonatomic, weak) CALayer *norLayer;
@end
static int _count = 0;
@implementation ZYDrawView
- (UIBezierPath *)bezierPath
{
if (_bezierPath == nil) {
_bezierPath = [[UIBezierPath alloc] init];
}
return _bezierPath;
}
- (void)awakeFromNib
{
CAReplicatorLayer *replicatorLayer = [CAReplicatorLayer layer];
replicatorLayer.frame = self.bounds;
[self.layer addSublayer:replicatorLayer];
CALayer *layer = [CALayer layer];
layer.frame = CGRectMake(0, -200, 10, 10);
layer.cornerRadius = layer.frame.size.width * 0.5;
layer.backgroundColor = [UIColor redColor].CGColor;
[replicatorLayer addSublayer:layer];
self.replicatorLayer = replicatorLayer;
self.norLayer = layer;
}
- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event
{
CGPoint curPoint = [[touches anyObject] locationInView:self];
[self.bezierPath moveToPoint:curPoint];
}
- (void)touchesMoved:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event
{
_count++;
CGPoint curPoint = [[touches anyObject] locationInView:self];
[self.bezierPath addLineToPoint:curPoint];
[self setNeedsDisplay];
}
- (void)startAnimation
{
CAKeyframeAnimation *keyframeAn = [CAKeyframeAnimation animationWithKeyPath:@"position"];
keyframeAn.path = self.bezierPath.CGPath;
keyframeAn.duration = 4;
keyframeAn.repeatCount = MAXFLOAT;
[self.norLayer addAnimation:keyframeAn forKey:nil];
self.replicatorLayer.instanceCount = _count;
self.replicatorLayer.instanceDelay = 0.1;
}
- (void)reDraw
{
_bezierPath = nil;
_count = 1;
[self.norLayer removeAllAnimations];
[self setNeedsDisplay];
}
- (void)drawRect:(CGRect)rect
{
[self.bezierPath stroke];
}
@end
以上内容是小编给大家介绍的Core Animation一些Demo总结 （动态切换图片、大转盘、图片折叠、进度条等动画效果），希望对大家以上帮助！
注：相关教程知识阅读请移步到Android开发频道。
