(自己截了几张图 随便用PS做了几张简单动画)
项目需求要做一个类似网易严选的上拉刷新动画（（下拉到一定角度的时候两个小圆球分离 然后开始旋转 上推的时候两个小圆球缓慢重合起来））
实现原理
自定义UIView，然后添加两个画出两个小圆球，分离动画用最简单的UIView动画就好了，动起来是通过CAAnimation动画因为涉及的东西不是很难，下面就直接贴代码了
代码实现
先建个UIView 然后再添加两个小圆球
LQHeaderView.h
```
#import
#define SCREEN_HEIGHT [UIScreen mainScreen].bounds.size.height
#define SCREEN_WIDTH [UIScreen mainScreen].bounds.size.width
#define QUAN_Y 8
@interface LQHeaderView : UIView
@property (nonatomic , strong) UIView *leftView;
@property (nonatomic,strong) UIView * rightView;
-(void)viewwithwidth:(CGFloat)width;
@end
```
LQHeaderView.m
```
#import "LQHeaderView.h"
@interface LQHeaderView()
@end
@implementation LQHeaderView
-(void)viewwithwidth:(CGFloat)width{
CGFloat with = width-12-10;
_leftView = [[UIView alloc] initWithFrame:CGRectMake(SCREEN_WIDTH/2, with,QUAN_Y,QUAN_Y)];
_leftView.backgroundColor = [UIColor redColor];
_leftView.layer.masksToBounds = YES;
_leftView.layer.cornerRadius =QUAN_Y/2;
[self addSubview:_leftView];
_rightView = [[UIView alloc] initWithFrame:CGRectMake(SCREEN_WIDTH/2, with,QUAN_Y,QUAN_Y)];
_rightView.backgroundColor = [UIColor blueColor];
_rightView.layer.masksToBounds = YES;
_rightView.layer.cornerRadius =QUAN_Y/2;
[self addSubview:_rightView];
}
@end
```
因为我要做的是下拉拉动画（下拉到一定角度的时候两个小圆球分离 然后开始旋转 上推的时候两个小圆球缓慢重合起来）我们项目上拉控件集成的MJRefresh 所以需要继承MJRefreshStateHeader
MJLQHeader.h
```
#import "MJRefreshStateHeader.h"
#import "LQHeaderView.h"
#define QUAN_Y 8
@interface MJLQHeader : MJRefreshStateHeader
@end
```
MJLQHeader
```
#import "MJLQHeader.h"
@interface MJLQHeader(){
LQHeaderView *_gifView;
CGFloat BGRefreshViewH;
CAAnimationGroup * groupTwoAnimation ;
CAAnimationGroup * groupOneAnimation ;
int stats;
}
@end
@implementation MJLQHeader
-(void)create{
self.mj_h = 30+5+5+5;
LQHeaderView *gifView = [[LQHeaderView alloc] init];
gifView.mj_x = 0;
gifView.mj_y = 0;
gifView.mj_w = self.mj_w;
gifView.mj_h = self.mj_h;
[self addSubview:_gifView = gifView];
[gifView viewwithwidth:self.mj_h];
BGRefreshViewH = self.mj_h -12-10;
_gifView.contentMode = UIViewContentModeCenter;
}
#pragma mark - 实现父类的方法
- (void)prepare
{
[super prepare];
self.mj_h = 30+5+5+5;
[self create];
// 初始化间距
// self.labelLeftInset = 20;
}
- (void)placeSubviews
{
[super placeSubviews];
}
- (void)setState:(MJRefreshState)state
{
MJRefreshCheckState
// 根据状态做事情
if(state == MJRefreshStatePulling){
[self fenli];
}else if(state == MJRefreshStateRefreshing){
[self oneYuanDian];
[self twoYuanDian];
}else if (state == MJRefreshStateIdle && stats!=102) {
[self stop];
} else if (state == MJRefreshStateIdle && stats ==102) {
[self fenli];;
}
}
//分离动画
-(void)fenli
{
stats =5;
[UIView animateWithDuration:0.5
animations:^{
_gifView.leftView.frame = CGRectMake(SCREEN_WIDTH/2+9,BGRefreshViewH, QUAN_Y, QUAN_Y);
_gifView.rightView.frame = CGRectMake(SCREEN_WIDTH/2-9,BGRefreshViewH, QUAN_Y, QUAN_Y);
}
completion:^(BOOL finished) {
}];
}
//重合动画
-(void)stop{
stats=5;
[UIView animateWithDuration:0.5 // 动画时长
animations:^{
[_gifView.rightView.layer removeAllAnimations];
[_gifView.leftView.layer removeAllAnimations];
_gifView.leftView.frame = CGRectMake(SCREEN_WIDTH/2,BGRefreshViewH, QUAN_Y, QUAN_Y);
_gifView.rightView.frame = CGRectMake(SCREEN_WIDTH/2,BGRefreshViewH, QUAN_Y, QUAN_Y);
}
completion:^(BOOL finished) {
// 动画完成后执行
// code...https://git.coding.net/Super-Rabbit/ShunLianDemo.git
// [self oneYuanDian];
// [self twoYuanDian];
_gifView.leftView.frame = CGRectMake(SCREEN_WIDTH/2,BGRefreshViewH, QUAN_Y, QUAN_Y);
_gifView.rightView.frame = CGRectMake(SCREEN_WIDTH/2,BGRefreshViewH, QUAN_Y, QUAN_Y);
}];
}
//动画开始
-(void)oneYuanDian{
// //位移动画
CAKeyframeAnimation *anima1 = [CAKeyframeAnimation animationWithKeyPath:@"position"];
UIBezierPath *arcPath = [UIBezierPath bezierPathWithArcCenter:CGPointMake(SCREEN_WIDTH/2, BGRefreshViewH) radius:9 startAngle:0 endAngle:M_PI*2 clockwise:YES];
anima1.path = arcPath.CGPath;
//组动画
groupOneAnimation = [CAAnimationGroup animation];
groupOneAnimation.animations = [NSArray arrayWithObjects:anima1, nil];
groupOneAnimation.duration = 0.9f;
groupOneAnimation.repeatCount= HUGE_VALF;
[groupOneAnimation setRemovedOnCompletion:NO];
[_gifView.leftView.layer addAnimation:groupOneAnimation forKey:@"groupAnimation"];
}
-(void)twoYuanDian{
// //位移动画
CAKeyframeAnimation *anima1 = [CAKeyframeAnimation animationWithKeyPath:@"position"];
UIBezierPath *arcPath = [UIBezierPath bezierPathWithArcCenter:CGPointMake(SCREEN_WIDTH/2, BGRefreshViewH) radius:9 startAngle:M_PI endAngle:M_PI*3 clockwise:YES];
anima1.path = arcPath.CGPath;
//组动画
groupTwoAnimation = [CAAnimationGroup animation];
groupTwoAnimation.animations = [NSArray arrayWithObjects:anima1, nil];
groupTwoAnimation.duration = 0.9f;
groupTwoAnimation.repeatCount= HUGE_VALF;
[groupTwoAnimation setRemovedOnCompletion:NO];
[_gifView.rightView.layer addAnimation:groupTwoAnimation forKey:@"groupAnimation"];
}
- (void)setPullingPercent:(CGFloat)pullingPercent
{
[super setPullingPercent:pullingPercent];
NSLog(@"pullingPercent %lf",pullingPercent);
NSString * string = [NSString stringWithFormat:@"%lf",pullingPercent];
if(pullingPercent>1.5 && stats==5 ){
[self oneYuanDian];
[self twoYuanDian];
stats=100;
}if([string isEqualToString:@"0.000000"]){
[self stopppp];
}
}
- (void)endRefreshing
{
[super endRefreshing];
stats =102;
}
//重合动画
-(void)stopppp{
stats=5;
[UIView animateWithDuration:0.5 // 动画时长
animations:^{
[_gifView.rightView.layer removeAllAnimations];
[_gifView.leftView.layer removeAllAnimations];
// _gifView.leftView.frame = CGRectMake(SCREEN_WIDTH/2,BGRefreshViewH, QUAN_Y, QUAN_Y);
// _gifView.rightView.frame = CGRectMake(SCREEN_WIDTH/2,BGRefreshViewH, QUAN_Y, QUAN_Y);
}
completion:^(BOOL finished) {
// 动画完成后执行
// code...https://git.coding.net/Super-Rabbit/ShunLianDemo.git
// [self oneYuanDian];
// [self twoYuanDian];
_gifView.leftView.frame = CGRectMake(SCREEN_WIDTH/2,BGRefreshViewH, QUAN_Y, QUAN_Y);
_gifView.rightView.frame = CGRectMake(SCREEN_WIDTH/2,BGRefreshViewH, QUAN_Y, QUAN_Y);
}];
}
@end
```
写的不是很清楚 git 上传了个 https://github.com/gjjggg/WYLQMJRefresh.git
