我们都知道 APP启动时加载的是LaunchImage 这张静态图。现在好多应用启动时都是动态的,并且右上角可选择跳过。

这里介绍一下自己在做这种动画时的一种方案。

启动图依然是加载的，只不过是一闪而过，这时候我想到的是拿到当前的LaunchImage图片，然后进行处理，造成一种改变了LaunchImage动画的假象。

思路如下:

根据UIBezierPath和CAShapeLayer自定义倒计时进度条，适用于app启动的时候设置一个倒计时关闭启动页面。可以设置进度条颜色，填充颜色，进度条宽度以及点击事件等。

一、设置跳过按钮

ZLDrawCircleProgressBtn.h:

/**
 *  set complete callback
 *
 *  @param lineWidth line width
 *  @param block     block
 *  @param duration  time
 */
- (void)startAnimationDuration:(CGFloat)duration withBlock:(DrawCircleProgressBlock )block;

ZLDrawCircleProgressBtn.m :

先初始化相关跳过按钮及进度圈:

// 底部进度条圈
@property (nonatomic, strong) CAShapeLayer *trackLayer;
// 表层进度条圈
@property (nonatomic, strong) CAShapeLayer *progressLayer;
@property (nonatomic, strong) UIBezierPath *bezierPath;
@property (nonatomic, copy)   DrawCircleProgressBlock myBlock;

- (instancetype)initWithFrame:(CGRect)frame
{
    if (self == [super initWithFrame:frame]) {
        self.backgroundColor = [UIColor clearColor];
        
        [self.layer addSublayer:self.trackLayer];
        
    }
    return self;
}

- (UIBezierPath *)bezierPath {
    if (!_bezierPath) {
        
        CGFloat width = CGRectGetWidth(self.frame)/2.0f;
        CGFloat height = CGRectGetHeight(self.frame)/2.0f;
        CGPoint centerPoint = CGPointMake(width, height);
        float radius = CGRectGetWidth(self.frame)/2;
        
        _bezierPath = [UIBezierPath bezierPathWithArcCenter:centerPoint
                                                     radius:radius
                                                 startAngle:degreesToRadians(-90)
                                                   endAngle:degreesToRadians(270)
                                                  clockwise:YES];
    }
    return _bezierPath;
}

底部进度条圈:

- (CAShapeLayer *)trackLayer {
    if (!_trackLayer) {
        _trackLayer = [CAShapeLayer layer];
        _trackLayer.frame = self.bounds;
        // 圈内填充色
        _trackLayer.fillColor = self.fillColor.CGColor ? self.fillColor.CGColor : [UIColor clearColor].CGColor ;
        _trackLayer.lineWidth = self.lineWidth ? self.lineWidth : 2.f;
        // 底部圈色
        _trackLayer.strokeColor = self.trackColor.CGColor ? self.trackColor.CGColor : [UIColor colorWithRed:197/255.0 green:159/255.0 blue:82/255.0 alpha:0.3].CGColor ;
        _trackLayer.strokeStart = 0.f;
        _trackLayer.strokeEnd = 1.f;
        
        _trackLayer.path = self.bezierPath.CGPath;
    }
    return _trackLayer;
}

表层进度条圈:

- (CAShapeLayer *)progressLayer {
    
    if (!_progressLayer) {
        _progressLayer = [CAShapeLayer layer];
        _progressLayer.frame = self.bounds;
        _progressLayer.fillColor = [UIColor clearColor].CGColor;
        _progressLayer.lineWidth = self.lineWidth ? self.lineWidth : 2.f;
        _progressLayer.lineCap = kCALineCapRound;
        // 进度条圈进度色
        _progressLayer.strokeColor = self.progressColor.CGColor ? self.progressColor.CGColor  : [UIColor  colorWithRed:197/255.0 green:159/255.0 blue:82/255.0 alpha:1].CGColor;
        _progressLayer.strokeStart = 0.f;
        
        CABasicAnimation *pathAnimation = [CABasicAnimation animationWithKeyPath:@"strokeEnd"];
        pathAnimation.duration = self.animationDuration;
        pathAnimation.fromValue = @(0.0);
        pathAnimation.toValue = @(1.0);
        pathAnimation.removedOnCompletion = YES;
        pathAnimation.delegate = self;
        [_progressLayer addAnimation:pathAnimation forKey:nil];
        
        _progressLayer.path = _bezierPath.CGPath;
    }
    return _progressLayer;
}

设置代理回调:

#pragma mark -- CAAnimationDelegate
- (void)animationDidStop:(CAAnimation *)anim finished:(BOOL)flag {
    if (flag) {
        self.myBlock();
    }
}
#pragma mark ---
- (void)startAnimationDuration:(CGFloat)duration withBlock:(DrawCircleProgressBlock )block {
    self.myBlock = block;
    self.animationDuration = duration;
    [self.layer addSublayer:self.progressLayer];
}

二、启动页

ZLStartPageView.h :

露出 显示引导页面方法:

/**
 *  显示引导页面方法
 */
- (void)show;

ZLStartPageView.m :

1. 初始化启动页

// 启动页图
@property (nonatomic,strong) UIImageView *imageView;
// 跳过按钮
@property (nonatomic, strong) ZLDrawCircleProgressBtn *drawCircleBtn;

- (instancetype)initWithFrame:(CGRect)frame {
    
    if (self = [super initWithFrame:frame]) {
        
        // 1.启动页图片
        _imageView = [[UIImageView alloc]initWithFrame:frame];
        _imageView.contentMode = UIViewContentModeScaleAspectFill;
        _imageView.image = [UIImage imageNamed:@"LaunchImage_667h"];
        [self addSubview:_imageView];
        
        // 2.跳过按钮
        ZLDrawCircleProgressBtn *drawCircleBtn = [[ZLDrawCircleProgressBtn alloc]initWithFrame:CGRectMake(kscreenWidth - 55, 30, 40, 40)];
        drawCircleBtn.lineWidth = 2;
        [drawCircleBtn setTitle:@"跳过" forState:UIControlStateNormal];
        [drawCircleBtn setTitleColor:[UIColor  colorWithRed:197/255.0 green:159/255.0 blue:82/255.0 alpha:1] forState:UIControlStateNormal];
        drawCircleBtn.titleLabel.font = [UIFont systemFontOfSize:14];
        
        [drawCircleBtn addTarget:self action:@selector(removeProgress) forControlEvents:UIControlEventTouchUpInside];
        [self addSubview:drawCircleBtn];
        self.drawCircleBtn = drawCircleBtn;
        
    }
    return self;
}

2. 显示启动页且完成时候回调移除

- (void)show {
    //  progress 完成时候的回调
    __weak __typeof(self) weakSelf = self;
    [weakSelf.drawCircleBtn startAnimationDuration:showtime withBlock:^{
        [weakSelf removeProgress];
    }];
    
    UIWindow *window = [UIApplication sharedApplication].keyWindow;
    [window addSubview:self];
}

3. 移除启动页面

- (void)removeProgress {
    
    self.imageView.transform = CGAffineTransformMakeScale(1, 1);
    self.imageView.alpha = 1;
    
    [UIView animateWithDuration:0.3 animations:^{
        self.drawCircleBtn.hidden = NO;
        self.imageView.alpha = 0.05;
        self.imageView.transform = CGAffineTransformMakeScale(5, 5);
    } completion:^(BOOL finished) {
        
        self.drawCircleBtn.hidden = YES;
        [self.imageView removeFromSuperview];
    }];
}

三、动态启动页的显示代码放在AppDeleate中

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    
    self.window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
    self.window.rootViewController = [[UINavigationController alloc] initWithRootViewController:[[HomeViewController alloc] init]];
    [self.window makeKeyAndVisible];
    
    [self setupStartPageView];
    
    return YES;
}

设置启动页:

- (void)setupStartPageView {
    
    ZLStartPageView *startPageView = [[ZLStartPageView alloc] initWithFrame:self.window.bounds];
    [startPageView show];
}

这个时候就可以可以测试喽~

四、压缩文件截图

界面性问题可以根据自己项目需求调整即可, 具体可参考代码, 项目能够直接运行!