iOS开发-下拉刷新动画小球左右交换位置Indicator指示器效果

之前开发中实现下拉刷新动画小球左右交换位置Indicator指示器效果。

一、效果图

在这里插入图片描述

二、基础动画

CABasicAnimation类的使用方式就是基本的关键帧动画。

所谓关键帧动画，就是将Layer的属性作为KeyPath来注册，指定动画的起始帧和结束帧，然后自动计算和实现中间的过渡动画的一种动画方式。

可以查看

https://blog.csdn.net/gloryFlow/article/details/131991202

三、实现代码

3.1 代码实现动画

主要两个球实现CABasicAnimation动画，KeyPath是position

- (void)showAnimation:(UIView *)view from:(CGPoint)from toPosition:(CGPoint)to {
    CAMediaTimingFunction *defaultCurve = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionDefault];
    
    CAAnimationGroup *animationGroup;
    animationGroup = [CAAnimationGroup animation];
    animationGroup.removedOnCompletion = NO;
    animationGroup.timingFunction = defaultCurve;
    animationGroup.fillMode = kCAFillModeBoth;
    animationGroup.beginTime = CACurrentMediaTime();
    animationGroup.duration = 0.5;
    animationGroup.repeatCount = MAXFLOAT;
    
    CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:@"position"];
    animation.fromValue = [NSValue valueWithCGPoint:from];
    animation.toValue = [NSValue valueWithCGPoint:to]; // 终了帧
    
    CAKeyframeAnimation *scaleAnimation = [CAKeyframeAnimation animationWithKeyPath:@"transform.scale.xy"];
    scaleAnimation.values = @[@1.0,@0.5,@1.0];
    scaleAnimation.keyTimes = @[@0.0,@0.5,@1.0];
    
    NSArray *animations = @[animation,scaleAnimation];
    
    animationGroup.animations = animations;
    
    [view.layer addAnimation:animationGroup forKey:@"animationGroup"];
}

完整代码如下

#import "INRefreshBallLoading.h"
#import "UIColor+Addition.h"

static CGFloat kBallSize = 12.0;
static CGFloat kDistance = 15.0;

@interface INRefreshBallLoading ()

@property (nonatomic, strong) UIImageView *aballImageView;
@property (nonatomic, strong) UIImageView *bballImageView;

@end

@implementation INRefreshBallLoading

- (instancetype)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        [self addSubview:self.aballImageView];
        [self addSubview:self.bballImageView];
        [self layoutBallFrame];
    }
    return self;
}

- (void)layoutBallFrame {
    self.aballImageView.center = self.center;
    self.bballImageView.center = self.center;
}

- (void)displayPrecent:(CGFloat)precent {
    if (precent < 0) {
        precent = 0;
    }
    
    if (precent > 1.0) {
        precent = 1.0;
    }
    
    CGPoint centerCenter = self.center;
    CGPoint aBallCenter = self.aballImageView.center;
    CGPoint bBallCenter = self.bballImageView.center;
    
    aBallCenter.x = centerCenter.x - precent*kDistance;
    self.aballImageView.center = aBallCenter;
    self.aballImageView.transform = CGAffineTransformMakeScale(precent, precent);
    
    bBallCenter.x = centerCenter.x + precent*kDistance;
    self.bballImageView.center = bBallCenter;
    self.bballImageView.transform = CGAffineTransformMakeScale(precent, precent);
}

- (void)startAnimation {
    CGPoint centerCenter = self.center;
    CGFloat leftCenter = self.center.x - kDistance;
    CGFloat rightCenter = self.center.x + kDistance;

    [self showAnimation:self.aballImageView from:CGPointMake(leftCenter, centerCenter.y) toPosition:CGPointMake(rightCenter, centerCenter.y)];
    [self showAnimation:self.bballImageView from:CGPointMake(rightCenter, centerCenter.y) toPosition:CGPointMake(leftCenter, centerCenter.y)];
}

- (void)stopAnimation {
    [self.aballImageView.layer removeAnimationForKey:@"animationGroup"];
    [self.bballImageView.layer removeAnimationForKey:@"animationGroup"];
}

- (void)showAnimation:(UIView *)view from:(CGPoint)from toPosition:(CGPoint)to {
    CAMediaTimingFunction *defaultCurve = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionDefault];
    
    CAAnimationGroup *animationGroup;
    animationGroup = [CAAnimationGroup animation];
    animationGroup.removedOnCompletion = NO;
    animationGroup.timingFunction = defaultCurve;
    animationGroup.fillMode = kCAFillModeBoth;
    animationGroup.beginTime = CACurrentMediaTime();
    animationGroup.duration = 0.5;
    animationGroup.repeatCount = MAXFLOAT;
    
    CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:@"position"];
    animation.fromValue = [NSValue valueWithCGPoint:from];
    animation.toValue = [NSValue valueWithCGPoint:to]; // 终了帧
    
    CAKeyframeAnimation *scaleAnimation = [CAKeyframeAnimation animationWithKeyPath:@"transform.scale.xy"];
    scaleAnimation.values = @[@1.0,@0.5,@1.0];
    scaleAnimation.keyTimes = @[@0.0,@0.5,@1.0];
    
    NSArray *animations = @[animation,scaleAnimation];
    
    animationGroup.animations = animations;
    
    [view.layer addAnimation:animationGroup forKey:@"animationGroup"];
}

#pragma mark - SETTER/GETTER
- (UIImageView *)aballImageView {
    if (!_aballImageView) {
        _aballImageView = [[UIImageView alloc] initWithFrame:CGRectMake(0.0, 0.0, kBallSize, kBallSize)];
        _aballImageView.clipsToBounds = YES;
        _aballImageView.userInteractionEnabled = YES;
        _aballImageView.backgroundColor = [UIColor colorWithHexString:@"ff7e48"];
        _aballImageView.layer.cornerRadius = kBallSize/2;
        _aballImageView.layer.masksToBounds = YES;
    }
    return _aballImageView;
}

- (UIImageView *)bballImageView {
    if (!_bballImageView) {
        _bballImageView = [[UIImageView alloc] initWithFrame:CGRectMake(0.0, 0.0, kBallSize, kBallSize)];
        _bballImageView.clipsToBounds = YES;
        _bballImageView.userInteractionEnabled = YES;
        _bballImageView.backgroundColor = [UIColor colorWithHexString:@"fe4373"];
        _bballImageView.layer.cornerRadius = kBallSize/2;
        _bballImageView.layer.masksToBounds = YES;
    }
    return _bballImageView;
}

@end

3.2 MJRefresh使用该动画

我这里继承MJRefreshStateHeader

需要根据刷新控件的状态来执行开启动画与结束动画操作

刷新控件的状态如下

typedef NS_ENUM(NSInteger, MJRefreshState) {
    // 普通闲置状态
    MJRefreshStateIdle = 1,
    // 松开就可以进行刷新的状态
    MJRefreshStatePulling,
    // 正在刷新中的状态
    MJRefreshStateRefreshing,
    // 即将刷新的状态
    MJRefreshStateWillRefresh,
    // 所有数据加载完毕，没有更多的数据了
    MJRefreshStateNoMoreData
};

INRefreshHeader.h

#import "MJRefresh.h"
#import "INRefreshFourBallLoading.h"

@interface INRefreshHeader : MJRefreshStateHeader

@property (nonatomic, assign) BOOL showInsetTop;

@property (nonatomic, strong) INRefreshBallLoading *ballLoadingView;

@end

INRefreshHeader.m

@implementation INRefreshHeader

- (instancetype)initWithFrame:(CGRect)frame {
    if (self = [super initWithFrame:frame]) {
        self.lastUpdatedTimeLabel.hidden = YES;
        self.stateLabel.hidden = YES;
        
        [self addSubview:self.ballLoadingView];
    }
    return self;
}

- (INRefreshBallLoading *)ballLoadingView {
    if (!_ballLoadingView) {
        _ballLoadingView = [[INRefreshBallLoading alloc] initWithFrame:CGRectMake(0.0, 0.0, CGRectGetWidth([UIScreen mainScreen].bounds), self.bounds.size.height)];
    }
    return _ballLoadingView;
}


- (void)setState:(MJRefreshState)state {
    MJRefreshCheckState
    
    // 根据状态做事情
    if (state == MJRefreshStateIdle) {
        if (oldState == MJRefreshStateRefreshing) {
            self.ballLoadingView.alpha = 1.0;

            // 如果执行完动画发现不是idle状态，就直接返回，进入其他状态
            if (self.state != MJRefreshStateIdle) return;
            
            self.ballLoadingView.alpha = 1.0;

            [self.ballLoadingView stopAnimation];

        } else {
            [self.ballLoadingView stopAnimation];

        }
    } else if (state == MJRefreshStatePulling) {
        [self.ballLoadingView stopAnimation];

    } else if (state == MJRefreshStateRefreshing) {
        self.ballLoadingView.alpha = 1.0;
    }
}

- (void)prepare {
    [super prepare];
    self.mj_h = 60.0;
}

- (void)placeSubviews {
    [super placeSubviews];
    
    CGFloat centerX = self.mj_w * 0.5;
    CGFloat centerY = self.mj_h * 0.5;
    self.ballLoadingView.center = CGPointMake(centerX, centerY);
}

/** 当scrollView的contentOffset发生改变的时候调用 */
- (void)scrollViewContentOffsetDidChange:(NSDictionary *)change {
    [super scrollViewContentOffsetDidChange:change];
    NSLog(@"change:%@",change);
    
    CGPoint old = [change[@"old"] CGPointValue];
    CGPoint new = [change[@"new"] CGPointValue];
    
    CGFloat precent = -new.y/self.mj_h;
    [self.ballLoadingView displayIndicator:precent];
}

/** 当scrollView的contentSize发生改变的时候调用 */
- (void)scrollViewContentSizeDidChange:(NSDictionary *)change {
    [super scrollViewContentSizeDidChange:change];
}

/** 当scrollView的拖拽状态发生改变的时候调用 */
- (void)scrollViewPanStateDidChange:(NSDictionary *)change {
    [super scrollViewPanStateDidChange:change];
}

- (void)setShowInsetTop:(BOOL)showInsetTop {
    _showInsetTop = showInsetTop;
    
}

- (void)backInitState {
    
}

@end

3.3 具体的TableView使用

需要设置UITableView的下拉刷新操作：tableView.mj_header = header

- (void)configureRefresh {
    __weak typeof(self) weakSelf = self;
    INRefreshHeader *header = [INRefreshHeader headerWithRefreshingBlock:^{
        [weakSelf refreshData];
    }];
    
    INRefreshFooter *footer = [INRefreshFooter footerWithRefreshingBlock:^{
        [weakSelf loadMoreData];
    }];
    self.editView.tableView.mj_header = header;
    self.editView.tableView.mj_footer = footer;
}

- (void)refreshData {
    dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(1.0 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
        [self.editView.tableView.mj_header endRefreshing];
        [self.editView.tableView.mj_footer endRefreshing];
    });
}

- (void)loadMoreData {
    dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(1.0 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
        [self.editView.tableView.mj_header endRefreshing];
        [self.editView.tableView.mj_footer endRefreshing];
    });
}