iphone - 我的应用程序中的音频，播放暂停 slider

Question

伙计们，我在将 UISlider 合并到我的音频应用程序中时遇到错误，任何建议都会很好，这是我的第一个应用程序，我是新手......

轨道播放得很好，停止得也很好，但是当我尝试跳过应用程序崩溃时，我确信我错过了一些东西，只是需要对代码有一些新的了解，希望有人能提供建议......

NoGraceViewController.h

#import <UIKit/UIKit.h>
#import <AVFoundation/AVFoundation.h>

@interface NoGraceViewController : UIViewController<AVAudioPlayerDelegate> {
    AVAudioPlayer *audioPlayer;
    UISlider *volumeControl;
}

@property(nonatomic,retain)IBOutlet UISlider *volumeControl;
@property(nonatomic,retain) AVAudioPlayer *audioPlayer;
@property (weak, nonatomic) IBOutlet UITextField *timeLabel;
@property (weak, nonatomic) IBOutlet UISlider *skipSlider;

-(IBAction) nograceButton;

-(IBAction)playbutton;

-(IBAction)stopbutton;

-(IBAction)skipSliderMoved;

@end

NoGraceViewController.m

#import "NoGraceViewController.h"

@interface NoGraceViewController ()

@end

@implementation NoGraceViewController
@synthesize skipSlider;
@synthesize timeLabel;

-(IBAction) nograceButton { 
    [[UIApplication sharedApplication] openURL: [NSURL URLWithString:@"http://itunes.apple.com/us/album/no-grace-original-mix-single/id392597812?uo=4"]];
}

@synthesize audioPlayer;

- (IBAction)playbutton
{
    [audioPlayer play];

}

-(IBAction)stopbutton
{
    [audioPlayer stop];
}

- (IBAction)skipSliderMoved:(UISlider *)sender {
    self.audioPlayer.currentTime = self.audioPlayer.duration*sender.value;
}

- (void)viewDidLoad {
    [super viewDidLoad];
    NSURL *url=[NSURL fileURLWithPath:[[NSBundle mainBundle] pathForResource:@"001.mp3" ofType:nil]];

    NSError *error;
    audioPlayer = [[AVAudioPlayer alloc]initWithContentsOfURL:url error:&error];
    if (error)
    {
        NSLog(@"Error in audioPlayer: %@", 
              [error localizedDescription]);
    } else {
        audioPlayer.delegate = self;
        [audioPlayer prepareToPlay];
    }

}

- (void)viewDidUnload {
    [self setSkipSlider:nil];
    [self setTimeLabel:nil];

    self.volumeControl=nil;
    self.audioPlayer=nil;
}

-(void)updateDisplay { 
    self.skipSlider.value = self.audioPlayer.currentTime / self.audioPlayer.duration; 
    NSString *timeString = [[NSString alloc] initWithFormat:@"%d:%02d", (int)   self.audioPlayer.currentTime / 60,(int) self.audioPlayer.currentTime % 60];
    self.timeLabel.text = timeString;
}

@end

Answer 1

试试这个:

self.audioPlayer.currentTime = (self.audioPlayer.duration / 100) * sender.value;