ios中的夜间模式（通知中心）

这个夜间模式不是颜色反转的那种，其实很简单，就是在window上面铺了一层view，把这个view的变成黑色，在调一下透明度就ok了，下面给大家看看代码实现吧

- (instancetype)init
{
self = [super init];
if (self) {

NSNotificationCenter *center = [NSNotificationCenter defaultCenter];
[center addObserver:self selector:@selector(receiveNotifica:) name:@"heiyejianglin" object:nil];
// 白天模式
NSNotificationCenter *center2 = [NSNotificationCenter defaultCenter];
[center2 addObserver:self selector:@selector(receiveNotifica2:) name:@"limingjianglin" object:nil];

}
return self;
}

- (void)receiveNotifica:(NSNotification *)center
{
self.nigView.hidden = NO;
NSDictionary *dic = [NSDictionary dictionaryWithObjectsAndKeys:@"value",@"key", nil];
[[NSNotificationCenter defaultCenter]postNotificationName:@"limingjianglinla" object:@"香皂" userInfo: dic];
}

- (void)receiveNotifica2:(NSNotification *)center
{
self.nigView.hidden = YES;
NSDictionary *dic = [NSDictionary dictionaryWithObjectsAndKeys:@"value",@"key", nil];
[[NSNotificationCenter defaultCenter]postNotificationName:@"heiyejianglinla" object:@"香皂" userInfo: dic];
}

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
self.nigView = [[UIView alloc] initWithFrame:self.window.bounds];
self.nigView.userInteractionEnabled = NO;
self.nigView.hidden = YES;
self.nigView.backgroundColor = [UIColor blackColor];
self.nigView.alpha = 0.6;
[self.window addSubview:self.nigView];
[_nigView release];

return YES;
}

if (button) {
//        NSLog(@"是");

NSDictionary *dic = [NSDictionary dictionaryWithObjectsAndKeys:@"value",@"key", nil];
[[NSNotificationCenter defaultCenter]postNotificationName:@"heiyejianglin" object:@"香皂" userInfo: dic];
}else {
//        NSLog(@"否");

NSDictionary *dic = [NSDictionary dictionaryWithObjectsAndKeys:@"value",@"key", nil];
[[NSNotificationCenter defaultCenter]postNotificationName:@"limingjianglin" object:@"香皂" userInfo: dic];
}