Use CADisplayLink to implement jelly effect animation (learned from Glow Technical Team) and cadisplaylinkglow

Use CADisplayLink to implement jelly effect animation (learned from Glow Technical Team) and cadisplaylinkglow
Use CADisplayLink for jelly effect Animation
CADisplayLink object is a timer object that allows your application to synchronize its drawing to the refresh rate of the display.
Github

1. Define a View@ InterfaceJellyView ()
@ Property (strong, nonatomic) CADisplayLink * displayLink;
@ Property (nonatomic) CGFloat from;
@ Property (nonatomic) CGFloat;
@ Property (nonatomic) BOOL animating;@ End
2. Draw View and move path-(Void) drawRect :( CGRect) rect {
CALayer * layer = self. layer. presentationLayer;

CGFloat progress = 1;
If (! Self. animating ){
SS = 1;
} Else {
Progress = 1-(layer. position. y-self. to)/(self. from-self. );
}

CGFloat height = CGRectGetHeight (rect );
CGFloat deltaHeight = height/2 * (0.5-fabs (progress-0.5 ));

CGPoint topLeft = CGPointMake (0, deltaHeight );
CGPoint topRight = CGPointMake (CGRectGetWidth (rect), deltaHeight );
CGPoint bottomLeft = CGPointMake (0, height );
CGPoint bottomRight = CGPointMake (CGRectGetWidth (rect), height );

UIBezierPath * path = [UIBezierPathbezierPath];
[[UIColorblueColor] setFill];
[Path moveToPoint: topLeft];
[Path addQuadCurveToPoint: topRightcontrolPoint: CGPointMake (CGRectGetMidX (rect), 0)];
[Path addLineToPoint: bottomRight];
[Path addQuadCurveToPoint: bottomLeftcontrolPoint: CGPointMake (CGRectGetMidX (rect), height-deltaHeight)];
[Path closePath];
[Path fill];}
3. Add CADisplayLink-(Void) startAnimationFrom :( CGFloat) from to :( CGFloat) {
Self. from = from;
Self. to =;
Self. animating = YES;
If (self. displayLink = nil ){
Self. displayLink = [CADisplayLinkdisplayLinkWithTarget: selfselector: @ selector (tick :)];
[Self. displayLinkaddToRunLoop: [nsunloopcurrentrunloop]
ForMode: NSDefaultRunLoopMode];
}
}

-(Void) completeAnimation {
Self. animating = NO;
[Self. displayLinkinvalidate];
Self. displayLink = nil;
}

-(Void) tick :( CADisplayLink *) displayLink {
[SelfsetNeedsDisplay];}
4. CallCGFloat from = CGRectGetHeight (self. view. bounds)-CGRectGetHeight (self. blockView. bounds)/2; CGFloat to = 100; self. blockView. center = CGPointMake (self. blockView. center. x, from); [self. blockViewstartAnimationFrom: fromto: to];
[UIViewanimateWithDuration: 1 delay: 0 usingSpringWithDamping: 0.85 initialSpringVelocity: 0 options: 0 animations: ^ {
Self. blockView. center = CGPointMake (self. blockView. center. x, );
} Completion: ^ (BOOL finished) {[self. blockViewcompleteAnimation];}];