iOS开发中实现广告页的思路

参考XHLaunchAd https://github.com/CoderZhuXH/XHLaunchAd

温馨提示：由于有复制的代码，文章少长，建议在大屏上阅读，效果更佳！

看代码

+(XHLaunchAd *)imageAdWithImageAdConfiguration:(XHLaunchImageAdConfiguration *)imageAdconfiguration delegate:(id)delegate{
    XHLaunchAd *launchAd = [XHLaunchAd shareLaunchAd];
    if(delegate) launchAd.delegate = delegate;
    launchAd.imageAdConfiguration = imageAdconfiguration;
    return launchAd;
}

+(XHLaunchAd *)shareLaunchAd{
    static XHLaunchAd *instance = nil;
    static dispatch_once_t oneToken;
    dispatch_once(&oneToken,^{
        instance = [[XHLaunchAd alloc] init];
    });
    return instance;
}

- (instancetype)init{
    self = [super init];
    if (self) {
        XHWeakSelf
        [self setupLaunchAd];
        [[NSNotificationCenter defaultCenter] addObserverForName:UIApplicationWillEnterForegroundNotification object:nil queue:nil usingBlock:^(NSNotification * _Nonnull note) {
            [self setupLaunchAdEnterForeground];
        }];
        [[NSNotificationCenter defaultCenter] addObserverForName:UIApplicationDidEnterBackgroundNotification object:nil queue:nil usingBlock:^(NSNotification * _Nonnull note) {
            [self removeOnly];
        }];
        [[NSNotificationCenter defaultCenter] addObserverForName:XHLaunchAdDetailPageWillShowNotification object:nil queue:nil usingBlock:^(NSNotification * _Nonnull note) {
            weakSelf.detailPageShowing = YES;
        }];
        [[NSNotificationCenter defaultCenter] addObserverForName:XHLaunchAdDetailPageShowFinishNotification object:nil queue:nil usingBlock:^(NSNotification * _Nonnull note) {
            weakSelf.detailPageShowing = NO;
        }];
    }
    return self;
}

-(void)setupLaunchAd{
    UIWindow *window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
    window.rootViewController = [XHLaunchAdController new];
    window.rootViewController.view.backgroundColor = [UIColor clearColor];
    window.rootViewController.view.userInteractionEnabled = NO;
    window.windowLevel = UIWindowLevelStatusBar + 1;
    window.hidden = NO;
    window.alpha = 1;
    _window = window;
    /** 添加launchImageView */
    [_window addSubview:[[XHLaunchImageView alloc] initWithSourceType:_sourceType]];
    _window.backgroundColor = [UIColor redColor];
}

-(void)setImageAdConfiguration:(XHLaunchImageAdConfiguration *)imageAdConfiguration{
    _imageAdConfiguration = imageAdConfiguration;
    _launchAdType = XHLaunchAdTypeImage;
    [self setupImageAdForConfiguration:imageAdConfiguration];
}

/**图片*/
-(void)setupImageAdForConfiguration:(XHLaunchImageAdConfiguration *)configuration{
    if(_window == nil) return;
    [self removeSubViewsExceptLaunchAdImageView];
    XHLaunchAdImageView *adImageView = [[XHLaunchAdImageView alloc] init];
    [_window addSubview:adImageView];
    /** frame */
    if(configuration.frame.size.width>0 && configuration.frame.size.height>0) adImageView.frame = configuration.frame;
    if(configuration.contentMode) adImageView.contentMode = configuration.contentMode;
    /** webImage */
    if(configuration.imageNameOrURLString.length && XHISURLString(configuration.imageNameOrURLString)){ // 网络图片
        [XHLaunchAdCache async_saveImageUrl:configuration.imageNameOrURLString];    // 磁盘保存图片地址
        /** 自设图片 */
        if ([self.delegate respondsToSelector:@selector(xhLaunchAd:launchAdImageView:URL:)]) {  // 使用三方框架或自己加载网络图片
            [self.delegate xhLaunchAd:self launchAdImageView:adImageView URL:[NSURL URLWithString:configuration.imageNameOrURLString]];
        }else{
            if(!configuration.imageOption) configuration.imageOption = XHLaunchAdImageDefault;
            XHWeakSelf
            [adImageView xh_setImageWithURL:[NSURL URLWithString:configuration.imageNameOrURLString] placeholderImage:nil GIFImageCycleOnce:configuration.GIFImageCycleOnce options:configuration.imageOption GIFImageCycleOnceFinish:^{
                //GIF不循环,播放完成
                [[NSNotificationCenter defaultCenter] postNotificationName:XHLaunchAdGIFImageCycleOnceFinishNotification object:nil userInfo:@{@"imageNameOrURLString":configuration.imageNameOrURLString}];
                
            } completed:^(UIImage *image,NSData *imageData,NSError *error,NSURL *url){
                if(!error){
#pragma clang diagnostic push
#pragma clang diagnostic ignored"-Wdeprecated-declarations"
                    if ([weakSelf.delegate respondsToSelector:@selector(xhLaunchAd:imageDownLoadFinish:)]) {
                        [weakSelf.delegate xhLaunchAd:self imageDownLoadFinish:image];
                    }
#pragma clang diagnostic pop
                    if ([weakSelf.delegate respondsToSelector:@selector(xhLaunchAd:imageDownLoadFinish:imageData:)]) {
                        [weakSelf.delegate xhLaunchAd:self imageDownLoadFinish:image imageData:imageData];
                    }
                }
            }];
            if(configuration.imageOption == XHLaunchAdImageCacheInBackground){
                /** 缓存中未有 */
                if(![XHLaunchAdCache checkImageInCacheWithURL:[NSURL URLWithString:configuration.imageNameOrURLString]]){
                    [self removeAndAnimateDefault]; return; /** 完成显示 */
                }
            }
        }
    }else{  // 本地图片
        if(configuration.imageNameOrURLString.length){
            NSData *data = XHDataWithFileName(configuration.imageNameOrURLString);
            if(XHISGIFTypeWithData(data)){
                FLAnimatedImage *image = [FLAnimatedImage animatedImageWithGIFData:data];
                adImageView.animatedImage = image;
                adImageView.image = nil;
                __weak typeof(adImageView) w_adImageView = adImageView;
                adImageView.loopCompletionBlock = ^(NSUInteger loopCountRemaining) {
                    if(configuration.GIFImageCycleOnce){
                        [w_adImageView stopAnimating];
                        XHLaunchAdLog(@"GIF不循环,播放完成");
                        [[NSNotificationCenter defaultCenter] postNotificationName:XHLaunchAdGIFImageCycleOnceFinishNotification object:@{@"imageNameOrURLString":configuration.imageNameOrURLString}];
                    }
                };
            }else{
                adImageView.animatedImage = nil;
                adImageView.image = [UIImage imageWithData:data];
            }
#pragma clang diagnostic push
#pragma clang diagnostic ignored"-Wdeprecated-declarations"
            if ([self.delegate respondsToSelector:@selector(xhLaunchAd:imageDownLoadFinish:)]) {
                [self.delegate xhLaunchAd:self imageDownLoadFinish:[UIImage imageWithData:data]];
            }
#pragma clang diagnostic pop
        }else{
            XHLaunchAdLog(@"未设置广告图片");
        }
    }
    /** skipButton */
    [self addSkipButtonForConfiguration:configuration];
    [self startSkipDispathTimer];
    /** customView */
    if(configuration.subViews.count>0)  [self addSubViews:configuration.subViews];
    XHWeakSelf
    adImageView.click = ^(CGPoint point) {
        [weakSelf clickAndPoint:point];
    };
}

疑问

1.XH中的window是怎么显示的？
设置了UIWindowLevelStatusBar属性

window.windowLevel = UIWindowLevelStatusBar + 1;

创建的window不用添加到任何控件上，创建完后就自动添加到window上了，但要想优先显示windowLevel 必须大于等于当前的window level 才会展示在上层。
[[UIApplication sharedApplication] keyWindow]获取正在显示的UIWindow是极其不准确的
销毁window的正确方式：
window.hidden = YES;
window = nil;
（注：iOS之后使用了SceneDelegate需要进行适配 https://www.jianshu.com/p/60bab1258efc）

自定义

1.用自己的方式加载图片

/**
 如果你想用SDWebImage等框架加载网络广告图片,请实现此代理,注意:实现此方法后,图片缓存将不受XHLaunchAd管理
 @param launchAd          XHLaunchAd
 @param launchAdImageView launchAdImageView
 @param url               图片url
 */
-(void)xhLaunchAd:(XHLaunchAd *)launchAd launchAdImageView:(UIImageView *)launchAdImageView URL:(NSURL *)url;

实现该代理便能用我们自己的方式去加载图片，如使用YYWebImage去加载webp格式的图片。

思路

1.使用一个单例来加载广告页
2.创建一个配置类对象，设置所需的一些配置，如：图片地址、图片位置、倒计时类型等，并把这个配置类赋值给单例的相应属性
3.创建一个window，在该window上添加广告页