1.设置系统音量
MPVolumeView *volumeView = [MPVolumeView new];
volumeView.showsRouteButton = NO;
volumeView.showsVolumeSlider = NO;
[self.view addSubview:volumeView];
__weak __typeof(self)weakSelf = self;
[[volumeView subviews] enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
if ([obj isKindOfClass:[UISlider class]]) {
__strong __typeof(weakSelf)strongSelf = weakSelf;
strongSelf.volumeSlider = obj;
*stop = YES;
}
}];
[self.volumeSlider setValue:1.0 animated:YES];
2.注册通知
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(volumeChanged:) name:@"AVSystemController_SystemVolumeDidChangeNotification" object:nil];
3.监听通知
-(void)volumeChanged:(NSNotification *)notification{
float volume = [[[notification userInfo] objectForKey:@"AVSystemController_AudioVolumeNotificationParameter"] floatValue];
NSLog(@"FlyElephant-系统音量:%f", volume);
}
4.移除通知
[[NSNotificationCenter defaultCenter] removeObserver:self name:@"AVSystemController_SystemVolumeDidChangeNotification" object:nil];
