音乐播放器

#import "RootViewController.h"

@interface RootViewController ()
{
    UITableView * table;
    NSMutableArray * dataSource;
}
@end

@implementation RootViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
    dataSource = [[NSMutableArray alloc]init];
    NSString * path = [[NSBundle mainBundle]pathForResource:@"songsName" ofType:@"plist"];
    NSArray * arr = [NSArray arrayWithContentsOfFile:path];
    [dataSource addObjectsFromArray:arr];
    
    table = [[UITableView alloc]initWithFrame:CGRectMake(0, 30, 320, 480 - 30) style:UITableViewStylePlain];
    table.delegate =self;
    table.dataSource = self;
    [self.view addSubview:table];
    self.automaticallyAdjustsScrollViewInsets = NO;
    //为表格视图添加背景图片
    UIImageView * imageView = [[UIImageView alloc]initWithFrame:CGRectMake(0, 0, 320, 480)];
    imageView.image = [UIImage imageNamed:@"56.jpg"];
    table.backgroundView = imageView;
    
}
-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    return [dataSource count];
}
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString * string = @"string";
    UITableViewCell * cell = [tableView dequeueReusableCellWithIdentifier:string];
    if(cell == nil)
    {
        cell = [[[UITableViewCell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:string]autorelease];
    }
    cell.textLabel.text = [dataSource objectAtIndex:indexPath.row];
    cell.backgroundColor = [UIColor clearColor];
    return cell;
}
-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    NSString * songName = [dataSource objectAtIndex:indexPath.row];
    
    //向上一个界面发送通知传递歌曲名称
    [[NSNotificationCenter defaultCenter] postNotificationName:@"songName" object:songName];
    
    [self dismissViewControllerAnimated:YES completion:nil];
}

//  MainViewController.h

#import <UIKit/UIKit.h>
#import <AVFoundation/AVFoundation.h>
@interface MainViewController : UIViewController<AVAudioPlayerDelegate>

@property (retain, nonatomic) IBOutlet UILabel *songLabel;
- (IBAction)pressPlay:(id)sender;
- (IBAction)pressStop:(id)sender;
@property (retain, nonatomic) IBOutlet UILabel *timeLabel;
- (IBAction)progressSlider:(id)sender;
- (IBAction)voiceSlider:(id)sender;
- (IBAction)changSong:(id)sender;
@property (retain, nonatomic) IBOutlet UISlider *progress;
@property (retain, nonatomic) IBOutlet UISlider *voice;

@end

//
//  MainViewController.m

#import "MainViewController.h"
#import "RootViewController.h"
@interface MainViewController ()
{
    RootViewController * root;
}
@property (nonatomic,retain) NSMutableArray * dataSource;
//接收歌曲的名称
@property (nonatomic,retain) NSString * songName;
@property (nonatomic,retain) AVAudioPlayer * player;


@end

@implementation MainViewController


- (void)viewDidLoad
{
    [super viewDidLoad];
    //存放所有的歌曲名称
    self.dataSource = [[NSMutableArray alloc]init];
    //读取plist文件中的内容
    NSString * path = [[NSBundle mainBundle]pathForResource:@"songsName" ofType:@"plist"];
    NSArray * arr = [NSArray arrayWithContentsOfFile:path];
    [self.dataSource addObjectsFromArray:arr];
    
    //判断此时歌曲名称是否为空
    if(self.songName.length == 0)
    {
        self.songName = @"蓝莲花";
    }
    self.songLabel.text = self.songName;
    
    //准备播放音乐
    //<1>找到要播放的音乐的路径
    NSString * songPath = [[NSBundle mainBundle]pathForResource:@"蓝莲花" ofType:@"mp3"];    //设置了第一首歌
    //<2>将本地路径转化成NSURL
    NSURL * url = [NSURL fileURLWithPath:songPath];
    //<3>初始化音乐播放器对象
    self.player = [[AVAudioPlayer alloc]initWithContentsOfURL:url error:nil];
    //<4>设置代理
    self.player.delegate = self;
    //<5>准备播放音乐
    //在播放音乐之前 先将音乐存放在缓存区中 防止播放的过程中出现卡顿
    [self.player prepareToPlay];
    
    root = [[RootViewController alloc]init];
    
    //为通知中心添加观察者
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(changeSongPlay:) name:@"songName" object:nil];
    
}
//接收到通知触发的方法
-(void)changeSongPlay:(NSNotification *)notification
{
    self.songName = [notification object];
    self.songLabel.text = self.songName;
    if(self.player != nil)//如果当前音乐正在播放 不设置的话会两首歌一起
    {
        [self.player stop];
        self.player = nil;
    }
    NSString *path = [[NSBundle mainBundle] pathForResource:self.songName ofType:@"mp3"];
    NSURL * url = [NSURL fileURLWithPath:path];
    self.player = [[AVAudioPlayer alloc]initWithContentsOfURL:url error:nil];
    self.player.delegate = self;
    
    [self.player prepareToPlay];
    
    
    [self pressPlay:nil];
}

- (IBAction)pressPlay:(id)sender
{
    [self.player play];
    
    [NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector(timeChange) userInfo:nil repeats:YES];
}
-(void)timeChange
{
    //获取当前音乐的总时间  按秒
    NSTimeInterval allTime = self.player.duration;
    int MM = (int)allTime / 60;
    int SS = (int)allTime % 60;
    NSString * allStr = [NSString stringWithFormat:@"%.2d:%.2d",MM,SS];
    //.2  一位数时前面会保留一个0
    
    //获取当前音乐播放到的时间
    NSTimeInterval currentTime = self.player.currentTime;
    int mm = (int)currentTime / 60;
    int ss = (int)currentTime % 60;
    NSString * currentStr = [NSString stringWithFormat:@"%.2d:%.2d",mm,ss];
    
    NSString * string = [NSString stringWithFormat:@"%@/%@",currentStr,allStr];
    
    self.timeLabel.text = string;
    //设置进度
    self.progress.value = currentTime / allTime;
}
- (IBAction)pressStop:(id)sender
{
    if([self.player isPlaying])
    {
        [self.player stop];
        //[self.player pause];
    }
}
- (IBAction)progressSlider:(id)sender
{
    //<1>暂停音乐
    [self pressStop:nil];
    
    UISlider * slider = (UISlider *)sender;
    
    self.player.currentTime = slider.value * self.player.duration;
    //播放音乐
    [self pressPlay:nil];
}

- (IBAction)voiceSlider:(id)sender
{
    UISlider * slider = (UISlider *)sender;
    [self.player setVolume:slider.value * 20];
}
- (IBAction)changSong:(id)sender
{
    [self presentViewController:root animated:YES completion:nil];
}
@end