#import "DDJelloView.h"
#define SYS_DEVICE_WIDTH ([[UIScreen mainScreen] bounds].size.width) // 屏幕宽度
#define SYS_DEVICE_HEIGHT ([[UIScreen mainScreen] bounds].size.height) // 屏幕长度
#define MIN_HEIGHT 50 // 图形最小高度
@interface DDJelloView ()
@property (nonatomic, assign) CGFloat mHeight;
@property (nonatomic, assign) CGFloat curveX; // r5点x坐标
@property (nonatomic, assign) CGFloat curveY; // r5点y坐标
@property (nonatomic, strong) UIView *curveView; // r5红点
@property (nonatomic, strong) CAShapeLayer *shapeLayer;
@property (nonatomic, strong) CADisplayLink *displayLink;
@property (nonatomic, assign) BOOL isAnimating;
@end
@implementation DDJelloView
static NSString *kX = @"curveX";
static NSString *kY = @"curveY";
- (instancetype)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if(self)
{
[self addObserver:self forKeyPath:kX options:NSKeyValueObservingOptionNew context:nil];
[self addObserver:self forKeyPath:kY options:NSKeyValueObservingOptionNew context:nil];
[self configShapeLayer];
[self configCurveView];
[self configAction];
}
return self;
}
- (void)dealloc {
[self removeObserver:self forKeyPath:kX];
[self removeObserver:self forKeyPath:kY];
}
- (void)drawRect:(CGRect)rect
{
}
-(void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary<NSString *,id> *)change context:(void *)context {
if ([keyPath isEqualToString:kX] || [keyPath isEqualToString:kY]) {
[self updateShapeLayerPath];
}
}
#pragma mark -
#pragma mark - Configuration
- (void)configAction
{
_mHeight = 100; // 手势移动时相对高度
_isAnimating = NO; // 是否处于动效状态
// 手势
UIPanGestureRecognizer *pan = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(handlePanAction:)];
self.userInteractionEnabled = YES;
[self addGestureRecognizer:pan];
// CADisplayLink默认每秒运行60次calculatePath是算出在运行期间_curveView的坐标，从而确定_shapeLayer的形状
_displayLink = [CADisplayLink displayLinkWithTarget:self selector:@selector(calculatePath)];
[_displayLink addToRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
_displayLink.paused = YES;
}
- (void)configShapeLayer
{
_shapeLayer = [CAShapeLayer layer];
// _shapeLayer.fillColor = [UIColor colorWithRed:57/255.0 green:67/255.0 blue:89/255.0 alpha:1.0].CGColor;
_shapeLayer.fillColor = [UIColor redColor].CGColor;
[self.layer addSublayer:_shapeLayer];
}
- (void)configCurveView
{
// _curveView就是r5点
self.curveX = SYS_DEVICE_WIDTH/2.0; // r5点x坐标
self.curveY = MIN_HEIGHT; // r5点y坐标
_curveView = [[UIView alloc] initWithFrame:CGRectMake(_curveX, _curveY, 3, 3)];
_curveView.backgroundColor = [UIColor redColor];
[self addSubview:_curveView];
}
#pragma mark -
#pragma mark - Action
- (void)handlePanAction:(UIPanGestureRecognizer *)pan
{
if(!_isAnimating)
{
if(pan.state == UIGestureRecognizerStateChanged)
{
// 手势移动时，_shapeLayer跟着手势向下扩大区域
CGPoint point = [pan translationInView:self];
// 这部分代码使r5红点跟着手势走
_mHeight = point.y*0.7 + MIN_HEIGHT;
self.curveX = SYS_DEVICE_WIDTH/2.0 + point.x;
self.curveY = _mHeight > MIN_HEIGHT ? _mHeight : MIN_HEIGHT;
_curveView.frame = CGRectMake(_curveX,
_curveY,
_curveView.frame.size.width,
_curveView.frame.size.height);
}
else if (pan.state == UIGestureRecognizerStateCancelled ||
pan.state == UIGestureRecognizerStateEnded ||
pan.state == UIGestureRecognizerStateFailed)
{
// 手势结束时,_shapeLayer返回原状并产生弹簧动效
_isAnimating = YES;
_displayLink.paused = NO; //开启displaylink,会执行方法calculatePath.
// 弹簧动效
[UIView animateWithDuration:1.0
delay:0.0
usingSpringWithDamping:0.5
initialSpringVelocity:0
options:UIViewAnimationOptionCurveEaseInOut
animations:^{
// 曲线点(r5点)是一个view.所以在block中有弹簧效果.然后根据他的动效路径,在calculatePath中计算弹性图形的形状
_curveView.frame = CGRectMake(SYS_DEVICE_WIDTH/2.0, MIN_HEIGHT, 3, 3);
} completion:^(BOOL finished) {
if(finished)
{
_displayLink.paused = YES;
_isAnimating = NO;
}
}];
}
}
}
- (void)updateShapeLayerPath
{
// 更新_shapeLayer形状
UIBezierPath *tPath = [UIBezierPath bezierPath];
[tPath moveToPoint:CGPointMake(0, 0)]; // r1点
[tPath addLineToPoint:CGPointMake(SYS_DEVICE_WIDTH, 0)]; // r2点
[tPath addLineToPoint:CGPointMake(SYS_DEVICE_WIDTH, MIN_HEIGHT)]; // r4点
[tPath addQuadCurveToPoint:CGPointMake(0, MIN_HEIGHT)
controlPoint:CGPointMake(_curveX, _curveY)]; // r3,r4,r5确定的一个弧线
[tPath closePath];
_shapeLayer.path = tPath.CGPath;
}
- (void)calculatePath
{
// 由于手势结束时,r5执行了一个UIView的弹簧动画,把这个过程的坐标记录下来,并相应的画出_shapeLayer形状
CALayer *layer = _curveView.layer.presentationLayer;
self.curveX = layer.position.x;
self.curveY = layer.position.y;
}
@end