iOS关于启动页自定义特殊处理

平常开发中对于启动页可能会有一些特别的要求，比如在启动页加动画或加一些按键可以响应事件等，最近项目中要在启动页增加版本号，因为版本号是不断的改变，所以要动态实现把它加到启动页上；在XCode上面配置的Launch Images Source或Launch Screen FIle(IOS8以上会优先调用这个作为启动项)都是保存一张静态图片；

原理：

其实原理也是很简单，启动页还是运用Launch Images Source的内容，然后在做一个视图在最上层，视图的背景用启动项的那张图，让人误以为还在启动中，启动页加载完成后，就显示这层视图，在2秒后再把这层视图删除，产生一个过度的假启动页效果；而我们自定义的动作就可以在这层视图上进行；下面将通过Coding.net的APP讲解这个功能；

一：创建一个视图EaseStartView

EaseStartView.h文件内容：

#import <UIKit/UIKit.h>

@interface EaseStartView : UIView
+ (instancetype)startView;

- (void)startAnimationWithCompletionBlock:(void(^)(EaseStartView *easeStartView))completionHandler;
@end

EaseStartView.m文件内容：

#import "EaseStartView.h"
#import <NYXImagesKit/NYXImagesKit.h>
#import "StartImagesManager.h"

@interface EaseStartView ()
@property (strong, nonatomic) UIImageView *bgImageView, *logoIconView;
@property (strong, nonatomic) UILabel *descriptionStrLabel;
@end

@implementation EaseStartView

+ (instancetype)startView{
    UIImage *logoIcon = [UIImage imageNamed:@"logo_coding_top"];
    StartImage *st = [[StartImagesManager shareManager] randomImage];
    return [[self alloc] initWithBgImage:st.image logoIcon:logoIcon descriptionStr:st.descriptionStr];
}

- (instancetype)initWithBgImage:(UIImage *)bgImage logoIcon:(UIImage *)logoIcon descriptionStr:(NSString *)descriptionStr{
    self = [super initWithFrame:kScreen_Bounds];
    if (self) {
        //add custom code
        UIColor *blackColor = [UIColor blackColor];
        self.backgroundColor = blackColor;

        _bgImageView = [[UIImageView alloc] initWithFrame:kScreen_Bounds];
        _bgImageView.contentMode = UIViewContentModeScaleAspectFill;
        _bgImageView.alpha = 0.0;
        [self addSubview:_bgImageView];

        [self addGradientLayerWithColors:@[(id)[blackColor colorWithAlphaComponent:0.4].CGColor, (id)[blackColor colorWithAlphaComponent:0.0].CGColor] locations:nil startPoint:CGPointMake(0.5, 0.0) endPoint:CGPointMake(0.5, 0.4)];

        _logoIconView = [[UIImageView alloc] init];
        _logoIconView.contentMode = UIViewContentModeScaleAspectFit;
        [self addSubview:_logoIconView];
        _descriptionStrLabel = [[UILabel alloc] init];
        _descriptionStrLabel.font = [UIFont systemFontOfSize:];
        _descriptionStrLabel.textColor = [UIColor colorWithWhite:1.0 alpha:0.5];
        _descriptionStrLabel.textAlignment = NSTextAlignmentCenter;
        _descriptionStrLabel.alpha = 0.0;
        [self addSubview:_descriptionStrLabel];

        [_descriptionStrLabel mas_makeConstraints:^(MASConstraintMaker *make) {
            make.centerX.equalTo(@[self, _logoIconView]);
            make.height.mas_equalTo();
            make.bottom.equalTo(self.mas_bottom).offset(-);
            make.left.equalTo(self.mas_left).offset();
            make.right.equalTo(self.mas_right).offset(-);
        }];

        [_logoIconView mas_makeConstraints:^(MASConstraintMaker *make) {
            make.centerX.equalTo(self);
            make.top.mas_equalTo(kScreen_Height/);
            make.width.mas_equalTo(kScreen_Width */);
            make.height.mas_equalTo(kScreen_Width/ */);
        }];

        [self configWithBgImage:bgImage logoIcon:logoIcon descriptionStr:descriptionStr];
    }
    return self;
}

- (void)configWithBgImage:(UIImage *)bgImage logoIcon:(UIImage *)logoIcon descriptionStr:(NSString *)descriptionStr{
    bgImage = [bgImage scaleToSize:[_bgImageView doubleSizeOfFrame] usingMode:NYXResizeModeAspectFill];
    self.bgImageView.image = bgImage;
    self.logoIconView.image = logoIcon;
    self.descriptionStrLabel.text = descriptionStr;
    [self updateConstraintsIfNeeded];
}

- (void)startAnimationWithCompletionBlock:(void(^)(EaseStartView *easeStartView))completionHandler{
    [[UIApplication sharedApplication].keyWindow
 addSubview:self];
    [[UIApplication sharedApplication].keyWindow
 bringSubviewToFront:self];
    _bgImageView.alpha = 0.0;
    _descriptionStrLabel.alpha = 0.0;

    @weakify(self);
    [UIView animateWithDuration:2.0 animations:^{
        @strongify(self);
        self.bgImageView.alpha = 1.0;
        self.descriptionStrLabel.alpha = 1.0;
    } completion:^(BOOL finished) {
        [UIView animateWithDuration:0.6 delay:0.3 options:UIViewAnimationOptionCurveEaseIn animations:^{
            @strongify(self);
            [self setX:-kScreen_Width];
        } completion:^(BOOL finished) {
            @strongify(self);
            [self removeFromSuperview];
            if (completionHandler) {
                completionHandler(self);
            }
        }];
    }];
}

@end

其实本实例中最为关键的内容在方法startAnimationWithCompletionBlock里

    [[UIApplication sharedApplication].keyWindow addSubview:self];
    [[UIApplication sharedApplication].keyWindow bringSubviewToFront:self];

代码就是把这个视图设置成在最前的最上层，这样就可以盖住程序中的页面；

    _bgImageView.alpha = 0.0;
    _descriptionStrLabel.alpha = 0.0;

这个是为了下面的动画做准备，若是直接用背景图可以把这两个都设置成0.99这样就不会有一闪的错觉；

    @weakify(self);
    [UIView animateWithDuration:2.0 animations:^{
        @strongify(self);
        self.bgImageView.alpha = 1.0;
        self.descriptionStrLabel.alpha = 1.0;
    } completion:^(BOOL finished) {
        [UIView animateWithDuration:0.6 delay:0.3 options:UIViewAnimationOptionCurveEaseIn animations:^{
            @strongify(self);
            [self setX:-kScreen_Width];
        } completion:^(BOOL finished) {
            @strongify(self);
            [self removeFromSuperview];
            if (completionHandler) {
                completionHandler(self);
            }
        }];
    }];

这边是动画效果，时间设置为2秒，因为这边第一个动画完还有一个左移出启动页的效果；当动画结束后就可以  [self removeFromSuperview];

二：调用启动页视图

在AppDelegate中的didFinishLaunchingWithOptions进行调用；

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
    // Override point for customization after application launch.
    self.window.backgroundColor = [UIColor whiteColor];

    //网络
    [[AFNetworkActivityIndicatorManager sharedManager] setEnabled:YES];
    [[AFNetworkReachabilityManager sharedManager] startMonitoring];

    //设置导航条样式
    [self customizeInterface];
    [[UIApplication sharedApplication] setStatusBarHidden:NO withAnimation:UIStatusBarAnimationFade];

    if ([Login isLogin]) {
        [self setupTabViewController];
    }else{
        [UIApplication sharedApplication].applicationIconBadgeNumber = ;
        [self setupIntroductionViewController];
    }
    [self.window makeKeyAndVisible];
    [FunctionIntroManager showIntroPage];

    EaseStartView *startView = [EaseStartView startView];
    @weakify(self);
    [startView startAnimationWithCompletionBlock:^(EaseStartView *easeStartView) {
        @strongify(self);
        //可以做其它事情
    }];

    return YES;
}

注意，EaseStartView代码的位置是要放在最后面，因为要让它盖在最上层，就要后面加载，这样就可以盖在登录页面上面或者主页上；到这就已经可以成功启动页的效果；

三：下面实例为项目中用到的动态加载版本号到启动页上

#import "StartUpView.h"

@interface StartUpView()
@property (strong, nonatomic) UIImageView *bgImageView;
@property (strong, nonatomic) UILabel *descriptionStrLabel;
@end

@implementation StartUpView

+ (instancetype)startView
{
    UIImage *bgImage=kshamLaunchImage;
    return [[self alloc] initWithBgImage:bgImage];
}

- (instancetype)initWithBgImage:(UIImage *)bgImage
{
    self = [super initWithFrame:Main_Screen_Bounds];
    if (self) {

        _bgImageView = [[UIImageView alloc] initWithFrame:Main_Screen_Bounds];
        _bgImageView.contentMode = UIViewContentModeScaleAspectFill;
        _bgImageView.alpha = ;
        _bgImageView.image=bgImage;
        [self addSubview:_bgImageView];

        _descriptionStrLabel = [[UILabel alloc] init];
        _descriptionStrLabel.font = [UIFont systemFontOfSize:];
        _descriptionStrLabel.textColor = [UIColor blackColor];
        _descriptionStrLabel.textAlignment = NSTextAlignmentCenter;
        _descriptionStrLabel.alpha = ;
        _descriptionStrLabel.text=[NSString stringWithFormat:@"版本号为:%@",appVersion];
        [self addSubview:_descriptionStrLabel];

        [_descriptionStrLabel mas_makeConstraints:^(MASConstraintMaker *make) {
            make.height.mas_equalTo();
            make.bottom.equalTo(self.mas_bottom).offset(-);
            make.left.equalTo(self.mas_left).offset();
            make.right.equalTo(self.mas_right).offset(-);
        }];
    }
    return self;
}

- (void)startAnimationWithCompletionBlock:(void(^)(StartUpView *easeStartView))completionHandler{
    [[UIApplication sharedApplication].keyWindow addSubview:self];
    [[UIApplication sharedApplication].keyWindow bringSubviewToFront:self];
    _bgImageView.alpha = 0.99;
    _descriptionStrLabel.alpha = 0.99;

    @weakify(self);
    [UIView animateWithDuration:2.0 animations:^{
        @strongify(self);
        self.bgImageView.alpha = 1.0;
        self.descriptionStrLabel.alpha = 1.0;
    } completion:^(BOOL finished) {
        [self removeFromSuperview];
        if (completionHandler) {
            completionHandler(self);
        }
    }];
}
@end

最近有个妹子弄的一个关于扩大眼界跟内含的订阅号，每天都会更新一些深度内容，在这里如果你感兴趣也可以关注一下(嘿对美女跟知识感兴趣)，当然可以关注后输入：github 会有我的微信号，如果有问题你也可以在那找到我；当然不感兴趣无视此信息；