- UIGravityBehavior为视图提供重力行为
-
UICollisionBehavior给视图增加碰撞边界
-
UIPushBehavior拖动view使用动画
-
UISnapBehavior拖动到指定位置
UIGravityBehavior的使用，如果运行就开始动画，则使用代码1，如果指定事件运行，这是用代码2
这里是代码实现
class ViewController: UIViewController{
//给UI组件添加重力效果
// UIGravityBehavior
var redView:UIView?
var animator:UIDynamicAnimator?
override func viewDidLoad() {
super.viewDidLoad()
redView = UIView.init(frame: CGRect.init(x: 100, y: 64, 100, height: 100))
if let theReadView = redView{
theReadView.backgroundColor = UIColor.red
view.addSubview(theReadView)
animator = UIDynamicAnimator.init(referenceView: view)
//这里是代码1
/*
if let theAnimator = animator{
let gravity = UIGravityBehavior.init(items: [theReadView])
theAnimator.addBehavior(gravity)
}
*/
}
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
//这里是代码2
if let theReadView = redView{
let gravity = UIGravityBehavior.init(items: [theReadView])
animator?.addBehavior(gravity)
}
}
}
这里可以看出来，RedView直接超出屏幕了，如果指定碰撞边界，或者防止两个碰撞重叠
UICollisionBehavior的使用
class ViewController: UIViewController{
//给UI组件添加重力效果
// UIGravityBehavior
var squareViews = [AnyObject]()
var animator:UIDynamicAnimator?
override func viewDidLoad() {
super.viewDidLoad()
let colors = [UIColor.red,UIColor.blue]
var currentCenterPoint = view.center
let eachSize = CGSize.init( 50, height: 50)
for counter in 0..<2{
let newView = UIView.init(frame: CGRect.init(x: 0, y: 0, eachSize.width, height: eachSize.height))
newView.backgroundColor = colors[counter]
newView.center = currentCenterPoint
currentCenterPoint.y += eachSize.height+10
squareViews.append(newView)
view.addSubview(newView)
}
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
animator = UIDynamicAnimator.init(referenceView: self.view)
/*创建重力*/
let gravity = UIGravityBehavior.init(items: squareViews as! [UIDynamicItem])
animator!.addBehavior(gravity)
/*创建碰撞监测*/
let collision = UICollisionBehavior.init(items: squareViews as! [UIDynamicItem])
collision.translatesReferenceBoundsIntoBoundary = true//确保动画对象使用父视图作为参考视图进行初始化
animator!.addBehavior(collision)
}
}
以上都是垂直下落，但是如果自己设置下落路线，可以使用UICollisionBehavior的方法
open func addBoundary(withIdentifier identifier: NSCopying, from p1: CGPoint, to p2: CGPoint)
//withIdentifier 边界标识符，如果传入改表示符，就可以得到该对象 from开始点 to结束点
collision.addBoundary(withIdentifier: "Identifier" as NSCopying, from: CGPoint.init(x: 0, y: 0), to: CGPoint.init(x: view.bounds.size.width-50, y: view.bounds.size.height-50))
效果图
UICollisionBehaviorDelegate的使用，如果想要监测不同物体间的碰撞，可以使用代理，
当一个物体碰撞另外一个物体会实现代理方法，
public func collisionBehavior(_ behavior: UICollisionBehavior, beganContactFor item: UIDynamicItem, withBoundaryIdentifier identifier: NSCopying?, at p: CGPoint)
当一个无物体脱离边界，不在于边界接触是，触发
public func collisionBehavior(_ behavior: UICollisionBehavior, endedContactFor item: UIDynamicItem, withBoundaryIdentifier identifier: NSCopying?)
class ViewController: UIViewController,UICollisionBehaviorDelegate{
//给UI组件添加重力效果
// UIGravityBehavior
var squareViews = [AnyObject]()
var animator:UIDynamicAnimator?
let bottomBoundary = "bottomBoundary"
override func viewDidLoad() {
super.viewDidLoad()
let colors = [UIColor.red,UIColor.green]
var currentCenterPoint = CGPoint.init(x: view.center.x, y: 0)
let eachSize = CGSize.init( 50, height: 50)
for counter in 0..<2{
let newView = UIView.init(frame: CGRect.init(x: 0, y: 0, eachSize.width, height: eachSize.height))
newView.backgroundColor = colors[counter]
newView.center = currentCenterPoint
currentCenterPoint.y += eachSize.height+10
squareViews.append(newView)
view.addSubview(newView)
}
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
animator = UIDynamicAnimator.init(referenceView: self.view)
/*创建重力*/
let gravity = UIGravityBehavior.init(items: squareViews as! [UIDynamicItem])
animator!.addBehavior(gravity)
/*创建碰撞监测*/
let collision = UICollisionBehavior.init(items: squareViews as! [UIDynamicItem])
collision.translatesReferenceBoundsIntoBoundary = true//确保动画对象使用父视图作为参考视图进行初始化
//withIdentifier 边界标识符，如果传入改表示符，就可以得到该对象 from开始点 to结束点
collision.addBoundary(withIdentifier: bottomBoundary as NSCopying, from: CGPoint.init(x: 0, y: view.bounds.size.height-100), to: CGPoint.init(x: view.bounds.size.width, y: view.bounds.size.height-100))
collision.collisionDelegate = self
animator!.addBehavior(collision)
}
//
public func collisionBehavior(_ behavior: UICollisionBehavior, beganContactFor item: UIDynamicItem, withBoundaryIdentifier identifier: NSCopying?, at p: CGPoint){
if identifier == nil{
return;
}
if identifier as? String == bottomBoundary{
UIView.animate(withDuration: 1, animations: {
let view = item as! UIView
view.backgroundColor = UIColor.red
view.alpha = 0
view.transform = CGAffineTransform.init(scaleX: 2, y: 2)
}) { (finish) in
let view = item as! UIView
behavior.removeItem(item)
view.removeFromSuperview()
}
}
}
}
UIPushBehavior的使用
class ViewController: UIViewController{
// UIPushBehavior 推动，需要设置推动的弧度和推动的力量值，就是angle和magnitude
var squareView :UIView?
var animator :UIDynamicAnimator?
var pushBehavior :UIPushBehavior?
//初始化squareView
func createSmallSquareView(){
squareView = UIView.init(frame: CGRect.init(x: 0, y: 0, 80, height: 80))
if let theSquareView = squareView{
theSquareView.backgroundColor = UIColor.green
theSquareView.center = view.center
view.addSubview(theSquareView)
}
}
func createGestureRecognizer(){
let gapGestureRecognizer = UITapGestureRecognizer.init(target: self, action: #selector(hadleTop(tap:)));
self.view.addGestureRecognizer(gapGestureRecognizer)
}
func createAnimatorAndBehaviors(){
animator = UIDynamicAnimator.init(referenceView: self.view)
if let theSquareView = squareView{
/*创建碰撞监测*/
let collision = UICollisionBehavior.init(items: [squareView] as! [UIDynamicItem])
collision.translatesReferenceBoundsIntoBoundary = true//确保动画对象使用父视图作为参考视图进行初始化
pushBehavior = UIPushBehavior.init(items: [theSquareView], mode: .continuous)
animator?.addBehavior(collision)
animator?.addBehavior(pushBehavior!)
}
}
override func viewDidLoad() {
super.viewDidLoad()
createGestureRecognizer()
createSmallSquareView()
createAnimatorAndBehaviors()
}
@objc func hadleTop(tap:UITapGestureRecognizer){
let tapPoint = tap.location(in: view)
let squareViewCenterPoint = self.squareView!.center
/*获取方块与中心点的距离*/
let deltax = tapPoint.x - squareViewCenterPoint.x
let dettay = tapPoint.y - squareViewCenterPoint.y
/*计算方块视图和点击触点的角度，从而得到推动的角度，用户监测两个点角度的公式*/
let angle = atan2(dettay, deltax)
pushBehavior!.angle = angle //设置推动的弧度
/*距离公式*/
let distanceBetweenPoints = sqrt(pow(tapPoint.x - squareViewCenterPoint.x, 2.0)+pow(tapPoint.y-squareViewCenterPoint.y, 2.0))
pushBehavior!.magnitude = distanceBetweenPoints/200.0//设置重力值，越大，相当于对于的力量越大，每一个点力量值会实现100点每平方秒的加速度
}
}
UISnapBehavior的使用
class ViewController: UIViewController{
// UIPushBehavior 推动，需要设置推动的弧度和推动的力量值，就是angle和magnitude
var squareView :UIView?
var animator :UIDynamicAnimator?
var snapBehavior :UISnapBehavior?
//初始化squareView
func createSmallSquareView(){
squareView = UIView.init(frame: CGRect.init(x: 0, y: 0, 80, height: 80))
if let theSquareView = squareView{
theSquareView.backgroundColor = UIColor.green
theSquareView.center = view.center
view.addSubview(theSquareView)
}
}
func createGestureRecognizer(){
let gapGestureRecognizer = UITapGestureRecognizer.init(target: self, action: #selector(hadleTop(tap:)));
self.view.addGestureRecognizer(gapGestureRecognizer)
}
func createAnimatorAndBehaviors(){
animator = UIDynamicAnimator.init(referenceView: self.view)
if let theSquareView = squareView{
/*创建碰撞监测*/
let collision = UICollisionBehavior.init(items: [squareView] as! [UIDynamicItem])
collision.translatesReferenceBoundsIntoBoundary = true//确保动画对象使用父视图作为参考视图进行初始化
snapBehavior = UISnapBehavior.init(item: theSquareView, snapTo: theSquareView.center)
snapBehavior!.damping = 0.5
animator?.addBehavior(collision)
animator?.addBehavior(snapBehavior!)
}
}
override func viewDidLoad() {
super.viewDidLoad()
createGestureRecognizer()
createSmallSquareView()
createAnimatorAndBehaviors()
}
@objc func hadleTop(tap:UITapGestureRecognizer){
let tapPoint = tap.location(in: view)
if let theSnap = snapBehavior{
animator!.removeBehavior(theSnap)
}
snapBehavior = UISnapBehavior.init(item: squareView!, snapTo: tapPoint)
snapBehavior!.damping = 0.5
animator?.addBehavior(snapBehavior!)
}
}