iOS 設置系統音量和監聽系統音量變化

很簡單的調用 

首先在工程引入MediaPlayer.framework

#import <MediaPlayer/MediaPlayer.h>

1. 獲取系統音量

// 獲取系統音量
MPVolumeView *volumeView = [[MPVolumeView alloc] init];

UISlider *volumeViewSlider= nil;

    for (UIView *view in [volumeView subviews]){

        if ([view.class.description isEqualToString:@"MPVolumeSlider"]){

            volumeViewSlider = (UISlider*)view;

            break;
        }
    }

 float systemVolume = volumeViewSlider.value;

 

2.監聽方法

  [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(volumeChanged:) name:@"AVSystemController_SystemVolumeDidChangeNotification" object:nil];

- (void)volumeChanged:(NSNotification *)notification
{
     [notification.userInfo[@"AVSystemController_AudioVolumeNotificationParameter"] floatValue];

}

 

 3.記得銷毀哦

- (void)dealloc
{

    [[NSNotificationCenter defaultCenter] removeObserver:self name:@"AVSystemController_SystemVolumeDidChangeNotification" object:nil];

}