IOS应用内调节音量如何弹出系统的音量图标

Answer 1

Compared with the user interface experience, you put a slider on the interface, and then when you drag the slider, the system's default volume icon will also appear to indicate the current volume. You can think about whether users like this design. If you have a volume slider, you generally don’t want to jump out of the system’s built-in volume interface

Answer 2

When you use the volume property of MPMusicPlayerController to adjust the volume, the picture you want will appear, but this method has been abandoned in 7.0