ios - 根据 mp3 的播放量更新 UIProgressView

Question

我一直在寻找一种简单的方法来在 UIProgressView 中显示播放 MP3 的进度。我有一种感觉，它将涉及一个 NSTimer 对象，但我不确定如何实现它。

这是我目前所拥有的。

#import "ViewController.h"

@interface ViewController ()

@property (weak, nonatomic) IBOutlet UISlider *VolumeLevel;
@property (weak, nonatomic) IBOutlet UIProgressView *progressBar;

@end

@implementation ViewController

AVAudioPlayer *player;


- (IBAction)play:(id)sender {

    [player play];

}

- (IBAction)pause:(id)sender {

    [player stop];

}
- (IBAction)volume:(id)sender {

    player.volume = _VolumeLevel.value;

}

- (void)viewDidLoad
{
    [super viewDidLoad];
    NSURL *songURL =[NSURL fileURLWithPath:[[NSBundle mainBundle]pathForResource:@"Gregory Is Here" ofType:@"mp3"]];
    player =[[AVAudioPlayer alloc]initWithContentsOfURL:songURL error:nil];
    player.volume = 0.5;


    // Do any additional setup after loading the view, typically from a nib.
}

Answer 1

使用 NSTImer，您可以:

- (IBAction)play:(id)sender {
    [player play];
    myTimer = [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(updateProgressBar) userInfo:nil repeats:YES];
}

- (IBAction)pause:(id)sender {
    [player stop];
    [myTimer invalidate];
}

- (void)updateProgressBar {
    float progress = player.currentTime / player.duration;
    [myProgressBar setProgress:progress animated:YES];
}

您可以更改计时器的 timeInterval 参数以增加或减少更新进度条的频率(1.0 为 1 秒)。