Uiview 如何使用CAKeyframeAnimation为形状的CoreGraphics绘制动画
我试图在UIView子类中为UIBeizerPath(在我的示例中为三角形)的绘图设置动画。但是,整个子视图正在设置动画,而不是形状 动画中有什么我遗漏的吗Uiview 如何使用CAKeyframeAnimation为形状的CoreGraphics绘制动画,uiview,core-animation,core-graphics,cakeyframeanimation,Uiview,Core Animation,Core Graphics,Cakeyframeanimation,我试图在UIView子类中为UIBeizerPath(在我的示例中为三角形)的绘图设置动画。但是,整个子视图正在设置动画,而不是形状 动画中有什么我遗漏的吗 - (void)drawRect:(CGRect)rect { CAShapeLayer *drawLayer = [CAShapeLayer layer]; drawLayer.frame = CGRectMake(0, 0, 100, 100); drawLayer.strokeColor
- (void)drawRect:(CGRect)rect {
CAShapeLayer *drawLayer = [CAShapeLayer layer];
drawLayer.frame = CGRectMake(0, 0, 100, 100);
drawLayer.strokeColor = [UIColor greenColor].CGColor;
drawLayer.lineWidth = 4.0;
[self.layer addSublayer:drawLayer];
UIBezierPath *path = [UIBezierPath bezierPath];
[path moveToPoint:CGPointMake(0,0)];
[path addLineToPoint:CGPointMake(50,100)];
[path addLineToPoint:CGPointMake(100,0)];
[path closePath];
CGPoint center = [self convertPoint:self.center fromView:nil];
[path applyTransform:CGAffineTransformMakeTranslation(center.x, center.y)];
[[UIColor redColor] set];
[path fill];
[[UIColor blueColor] setStroke];
path.lineWidth = 3.0f;
[path stroke];
CAKeyframeAnimation *pathAnimation = [CAKeyframeAnimation animationWithKeyPath:@"position"];
pathAnimation.duration = 4.0f;
pathAnimation.path = path.CGPath;
pathAnimation.calculationMode = kCAAnimationLinear;
[drawLayer addAnimation:pathAnimation forKey:@"position"];
}
- 您正在创建一个
,但没有使用它做任何有用的事情。让我们来解决这个问题CAShapeLayer
- 不要在
中设置图层和动画,因为这严格意义上是使用CoreGraphics或UIKit API进行绘图的时间。相反,您希望CAShapeLayer绘制三角形,这样您就可以为其设置动画-drawRect:
- CAKeyframeAnimation.path用于完全不同的对象(例如,沿路径移动层)
- 您的动画正在设置层的
值的动画。毫不奇怪,它会移动图层!您希望改为设置位置
值的动画路径
- CAKeyframeAnimation背后的思想是为其提供一个
,以将层的特性设置为。在关键帧之间的时间内,它将在两个相邻关键帧之间插值。所以你需要给它几条路径——每边一条值数组
- 插值任意路径是困难的。当路径具有相同数量和类型的元素时,CA的路径插值效果最佳。因此,我们要确保所有路径都具有相同的结构,只是有些点彼此重叠
- 动画的秘密,也许对一般的计算机来说:你必须精确地解释你想要发生什么。“我想为每个点的图形设置动画,使其看起来像是动画”,这几乎是不够的信息
-animate:
操作
SPAnimatedShapeView.h:
#import <UIKit/UIKit.h>
@interface SPAnimatedShapeView : UIView
- (IBAction)animate:(id)sender;
@end
#导入
@界面SPAnimatedShapeView:UIView
-(iAction)动画:(id)发送者;
@结束
SPAnimatedShapeView.m:
#import "SPAnimatedShapeView.h"
#import <QuartzCore/QuartzCore.h>
@interface SPAnimatedShapeView ()
@property (nonatomic, retain) CAShapeLayer* shapeLayer;
@end
@implementation SPAnimatedShapeView
@synthesize shapeLayer = _shapeLayer;
- (void)dealloc
{
[_shapeLayer release];
[super dealloc];
}
- (void)layoutSubviews
{
if (!self.shapeLayer)
{
self.shapeLayer = [[[CAShapeLayer alloc] init] autorelease];
self.shapeLayer.bounds = CGRectMake(0, 0, 100, 100); // layer is 100x100 in size
self.shapeLayer.position = self.center; // and is centered in the view
self.shapeLayer.strokeColor = [UIColor blueColor].CGColor;
self.shapeLayer.fillColor = [UIColor redColor].CGColor;
self.shapeLayer.lineWidth = 3.f;
[self.layer addSublayer:self.shapeLayer];
}
}
- (IBAction)animate:(id)sender
{
UIBezierPath* path0 = [UIBezierPath bezierPath];
[path0 moveToPoint:CGPointZero];
[path0 addLineToPoint:CGPointZero];
[path0 addLineToPoint:CGPointZero];
[path0 addLineToPoint:CGPointZero];
UIBezierPath* path1 = [UIBezierPath bezierPath];
[path1 moveToPoint:CGPointZero];
[path1 addLineToPoint:CGPointMake(50,100)];
[path1 addLineToPoint:CGPointMake(50,100)];
[path1 addLineToPoint:CGPointMake(50,100)];
UIBezierPath* path2 = [UIBezierPath bezierPath];
[path2 moveToPoint:CGPointZero];
[path2 addLineToPoint:CGPointMake(50,100)];
[path2 addLineToPoint:CGPointMake(100,0)];
[path2 addLineToPoint:CGPointMake(100,0)];
UIBezierPath* path3 = [UIBezierPath bezierPath];
[path3 moveToPoint:CGPointZero];
[path3 addLineToPoint:CGPointMake(50,100)];
[path3 addLineToPoint:CGPointMake(100,0)];
[path3 addLineToPoint:CGPointZero];
CAKeyframeAnimation* animation = [CAKeyframeAnimation animationWithKeyPath:@"path"];
animation.duration = 4.0f;
animation.values = [NSArray arrayWithObjects:(id)path0.CGPath, (id)path1.CGPath, (id)path2.CGPath, (id)path3.CGPath, nil];
[self.shapeLayer addAnimation:animation forKey:nil];
}
@end
#导入“SPAnimatedShapeView.h”
#进口
@接口SPAnimatedShapeView()
@属性(非原子,保留)CAShapeLayer*shapeLayer;
@结束
@实现SPAnimatedShapeView
@合成形状层=_形状层;
-(无效)解除锁定
{
[_ShapelayerRelease];
[super dealoc];
}
-(无效)布局子视图
{
如果(!self.shapeLayer)
{
self.shapeLayer=[[CAShapeLayer alloc]init]autorelease];
self.shapeLayer.bounds=CGRectMake(0,0,100,100);//层的大小为100x100
self.shapeLayer.position=self.center;//并且在视图中居中
self.shapeLayer.strokeColor=[UIColor blueColor].CGColor;
self.shapeLayer.fillColor=[UIColor redColor].CGColor;
self.shapeLayer.lineWidth=3.f;
[self.layer addSublayer:self.shapeLayer];
}
}
-(iAction)动画:(id)发送者
{
UIBezierPath*路径0=[UIBezierPath bezierPath];
[路径0移动点:CGPointZero];
[path0 addLineToPoint:CGPointZero];
[path0 addLineToPoint:CGPointZero];
[path0 addLineToPoint:CGPointZero];
UIBezierPath*路径1=[UIBezierPath bezierPath];
[path1 moveToPoint:CGPointZero];
[path1 addLineToPoint:CGPointMake(50100)];
[path1 addLineToPoint:CGPointMake(50100)];
[path1 addLineToPoint:CGPointMake(50100)];
UIBezierPath*路径2=[UIBezierPath bezierPath];
[path2 moveToPoint:CGPointZero];
[path2 addLineToPoint:CGPointMake(50100)];
[path2 addLineToPoint:CGPointMake(100,0)];
[path2 addLineToPoint:CGPointMake(100,0)];
UIBezierPath*path3=[UIBezierPath bezierPath];
[路径3移动点:CGPointZero];
[path3 addLineToPoint:CGPointMake(50100)];
[path3 addLineToPoint:CGPointMake(100,0)];
[path3 addLineToPoint:CGPointZero];
CAKeyframeAnimation*动画=[CAKeyframeAnimation animation WithKeyPath:@“path”];
animation.duration=4.0f;
animation.values=[NSArray arrayWithObjects:(id)path0.CGPath,(id)path1.CGPath,(id)path2.CGPath,(id)path3.CGPath,nil];
[self.shapeLayer addAnimation:animation-forKey:nil];
}
@结束
准确解释“为UIBezierPath绘制动画”的含义。你想让它一个接一个地画出各个部分,还是什么?@kurt是的,我想画出每个点的动画,使三角形看起来像动画一样。谢谢你的解释。这真的很有帮助。事实证明还有一种更简单的方法:使用cabasicanition
从0到1设置strokeEnd
属性的动画。