转载

IOS-UI-UIDynamic（二）

UIPushBehavior :推动效果

UIAttachmentBehavior：附着效果

UISnapBehavior：迅速移动效果

一.重要的属性

UIPushBehavior :推动效果

typedef NS_ENUM(NSInteger, UIPushBehaviorMode) {

UIPushBehaviorModeContinuous, 持续的力

UIPushBehaviorModeInstantaneous 瞬间的力

} NS_ENUM_AVAILABLE_IOS(7_0);

@property (nonatomic, readonly) UIPushBehaviorMode mode; 推动效果的样式

@property (nonatomic, readwrite) BOOL active; 是否激活

@property (readwrite, nonatomic) CGFloat angle; 推动角度

@property (readwrite, nonatomic) CGFloat magnitude; 推动力量

@property (readwrite, nonatomic) CGVector pushDirection; 推动的方向

UISnapBehavior：迅速移动效果

// The point argument is expressed in the reference coordinate system

- (instancetype)initWithItem:(id <UIDynamicItem>)item snapToPoint:(CGPoint)point;

迅速移动效果只能一次添加到一个元素上 snapToPoint 让他移动到哪一个点

@property (nonatomic, assign) CGFloat damping; // damping value from 0.0 to 1.0. 0.0 is the least oscillation. damping 的范围是（0.0-1.0）

UIAttachmentBehavior：附着效果

吸附着一个视图或者一个点（也可以多个连接）

附着效果一个视图与一个锚点或者另一个视图相连接的情况

附着行为描述的是两点之间的连接情况，可以模拟刚性或者弹性连接

在多个物体间设定多个UIAttachmentBehavior，可以模拟多物体连接

typedef NS_ENUM(NSInteger, UIAttachmentBehaviorType) {

UIAttachmentBehaviorTypeItems, 吸附一个元素

UIAttachmentBehaviorTypeAnchor 吸附一个点

} NS_ENUM_AVAILABLE_IOS(7_0);

设置吸附效果的样式

@property (readonly, nonatomic) UIAttachmentBehaviorType attachedBehaviorType;

@property (readwrite, nonatomic) CGPoint anchorPoint;锚点

@property (readwrite, nonatomic) CGFloat length;距离与锚点的距离

@property (readwrite, nonatomic) CGFloat damping; // 1: critical damping 跳跃度

@property (readwrite, nonatomic) CGFloat frequency; // in Hertz 幅度

二.代码

1.推动效果

 1 #import "ViewController.h"  2  3 @interface ViewController ()  4 {  5 UIDynamicAnimator * dynamicAnimator;  6 UIView *view1;  7  8 }  9 @end 10 11 @implementation ViewController 12 13 - (void)viewDidLoad { 14  [super viewDidLoad]; 15 dynamicAnimator = [[UIDynamicAnimator alloc]initWithReferenceView:self.view]; 16 view1 = [[UIView alloc]initWithFrame:CGRectMake(0, 0, 90, 90)]; 17 view1.backgroundColor = [UIColor redColor]; 18  [self.view addSubview:view1]; 19 UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(pushView)]; 20 21 [view1 addGestureRecognizer:tap];

- (void)pushView{ [dynamicAnimator removeAllBehaviors];//移除所有的效果 UIPushBehavior * push = [[UIPushBehavior alloc]initWithItems:@[view1] mode:UIPushBehaviorModeContinuous]; // mode的两个属性 // UIPushBehaviorModeContinuous,一直推动 // UIPushBehaviorModeInstantaneous 瞬间推动 push.pushDirection = CGVectorMake(1, 0); // x是正右，负左。y是正下负上。 push.magnitude = 5;//量级：既是推动力大小 //设置成NO时就不再响应效果 // push.active = NO; [dynamicAnimator addBehavior:push];//把推动效果添加到效果器上 }

2.瞬间移动效果(viewDidLoad里面添加另一个点击手势)

UITapGestureRecognizer *tap1 = [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(snap:)]; [self.view addGestureRecognizer:tap1];

之后

-(void)snap:(UITapGestureRecognizer *)send{ [dynamicAnimator removeAllBehaviors]; // 迅速移动效果 只能一次 添加到一个元素上 snapToPoint 让他移动到哪一个点 UISnapBehavior * snap = [[UISnapBehavior alloc]initWithItem:view1 snapToPoint:[send locationInView:self.view]]; //跳动幅度：0~1,值越小，跳动幅度越大 snap.damping = 0; [dynamicAnimator addBehavior:snap]; }

吸附效果

@interface ViewController () { UIDynamicAnimator * dynamicAnimator; UIView *view1; UIView *view2; } @end @implementation ViewController - (void)viewDidLoad { [super viewDidLoad]; dynamicAnimator = [[UIDynamicAnimator alloc]initWithReferenceView:self.view]; view1 = [[UIView alloc]initWithFrame:CGRectMake(0, 0, 90, 90)]; view1.backgroundColor = [UIColor redColor]; [self.view addSubview:view1]; view2 = [[UIView alloc]initWithFrame:CGRectMake(100, 100, 90, 90)]; view2.backgroundColor = [UIColor blueColor]; [self.view addSubview:view2]; UITapGestureRecognizer *tap2 = [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(attachment:)]; [self.view addGestureRecognizer:tap2]; }

-(void)attachment:(UITapGestureRecognizer *)send{ [dynamicAnimator removeAllBehaviors]; // 吸附到视图的某个点 UIAttachmentBehavior * attachment = [[UIAttachmentBehavior alloc]initWithItem:view1 offsetFromCenter:UIOffsetMake(20, 20) attachedToAnchor:[send locationInView:self.view]]; attachment.length = 50;//吸附范围 attachment.damping = 0.5; attachment.frequency = 5; [dynamicAnimator addBehavior:attachment]; // 两个元素吸附 // UIAttachmentBehavior *attachment1 = [[UIAttachmentBehavior alloc]initWithItem:view1 offsetFromCenter:UIOffsetMake(50, 50) attachedToItem:view2 offsetFromCenter:UIOffsetMake(50, 50)]; // attachment1.length = 50;//吸附范围 // attachment1.damping = 0.5; // attachment1.frequency = 50; // [dynamicAnimator addBehavior:attachment1];  }