
/*
不是技术性的文章,只是自己记录每天所学的方式。
-----------------------程序员的天空是去往星辰和大海
*/
-1-同样作为播放音乐文件的类,AvAudioPlayer音乐播放器常用于:
1.时间较长的音乐文件播放
2.可在音乐播放过程中进行操作
3.需要执行循环播放,播放暂停等要求
4.需要改变声音音道等属性
-2-准备工作:
1>导入AVFoundation.framework系统类库
2>关联头文件 #import <AVFoundation/AVFoundation.h>


-3-AVAudioPlayer的常用属性和基本方法
初始化方法:
_avPlayer=[[AVAudioPlayer alloc]initWithContentsOfURL:url error:nil];
准备方法
[_avPlayer PRepareToPlay];
开始播放歌曲
[_avPlayer play];
暂停播放的方法
[_avPlayer stop];
判断是否正在播放的方法
[_avPlayer isPlaying]
常用属性
duration :当前加载歌曲的总时长 为基本数据类型
currentTime 当前播放进度时间 也为基本数据类型
【特别注意】使用AVAudioPlayer需要注意一下几点
1. 每次加载歌曲,都必须将当前加载数据内容销毁 ,这是因为AVAudioPlayer每次有且只能加载一个文件
if([_avPlayer isPlaying]){
[_avPlayer stop];
_avPlayer=nil;
}
2.当设置了AVAudioPlayer代理方法时,必须在每次重新加载文件时,重新设置代理,这是因为_avPlayer=nil造成的
-4-简单的代码实现一个小型的音乐播放器
支持循环播放,音量调节,下一首播放 播放暂停及重新启动等功能

//
// RootViewController.m
// GGAvAudioPlayer
//
// Created by MS on 15-8-18.
// Copyright (c) 2015年 GG. All rights reserved.
//
#import "RootViewController.h"
@interface RootViewController ()<UITableViewDataSource,UITableViewDelegate,AVAudioPlayerDelegate>{
UITableView * _tableView;
NSMutableArray * _dataArray;
NSString * songName;
AVAudioPlayer * _avPlayer;
}
@end
@implementation RootViewController
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
[self creatDataSource];
[self creatUI];
}
//从plist文件中获取播放列表
-(void)creatDataSource{
_dataArray=[[NSMutableArray alloc]init];
NSString * str=[[NSBundle mainBundle]pathForResource:@"songsName" ofType:@"plist"];
NSArray * arr=[NSArray arrayWithContentsOfFile:str];
[_dataArray addObjectsFromArray:arr];
//songName 为当前播放歌曲名
songName=_dataArray[0];
}
//创建音乐列表UI
-(void)creatUI{
_tableView=[[UITableView alloc]initWithFrame:CGRectMake(0, 90, 320, 320) style:UITableViewStylePlain];
_tableView.delegate=self;
_tableView.dataSource=self;
[self.view addSubview:_tableView];
_nameLabel.text=songName;
//通过url高效的加载播放歌曲
NSURL * url=[NSURL fileURLWithPath:[[NSBundle mainBundle]pathForResource:songName ofType:@"mp3"]];
_avPlayer=[[AVAudioPlayer alloc]initWithContentsOfURL:url error:nil];
_avPlayer.delegate=self;
[_avPlayer prepareToPlay];
}
#pragma mark - UITableViewDelegate
-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{
return _dataArray.count;
}
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
static NSString * cellName=@"cellName";
UITableViewCell * cell=[tableView dequeueReusableCellWithIdentifier:cellName];
if(!cell){
cell=[[UITableViewCell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellName];
}
cell.textLabel.text=_dataArray[indexPath.row];
return cell;
}
-(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath{
return 40.0f;
}
-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath{
songName=[_dataArray objectAtIndex:indexPath.row];
_nameLabel.text=[_dataArray objectAtIndex:indexPath.row];
NSURL * url = [NSURL fileURLWithPath:[[NSBundle mainBundle]pathForResource:_nameLabel.text ofType:@"mp3" ]];
if([_avPlayer isPlaying]){
[_avPlayer stop];
_avPlayer=nil;
}
_avPlayer=[[AVAudioPlayer alloc]initWithContentsOfURL:url error:nil];
[_avPlayer prepareToPlay];
[_avPlayer play];
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
- (IBAction)volumeChanged:(id)sender {
UISlider * slider=(UISlider *)sender;
_avPlayer.volume=slider.value * 20;
}
- (IBAction)progressChanged:(id)sender {
UISlider * slider=(UISlider *)sender;
_avPlayer.currentTime=slider.value*_avPlayer.duration;
[self playBtn:nil];
}
- (IBAction)playBtn:(id)sender {
[_avPlayer play];
//加入计时器,计时为1秒
[NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector(timeChanged) userInfo:nil repeats:YES];
}
-(void)timeChanged{
NSInteger allTime = _avPlayer.duration;
NSInteger MM=allTime/60;
NSInteger SS=allTime%60;
NSInteger currtentTime=_avPlayer.currentTime;
NSInteger mm=currtentTime/60;
NSInteger ss=currtentTime%60;
NSString * str=[NSString stringWithFormat:@"%02d:%02d/%02d:%02d",mm,ss,MM,SS];
self.timeLabel.text=str;
self.progressSlider.value=_avPlayer.currentTime/_avPlayer.duration;
}
- (IBAction)nextBtn:(id)sender {
NSInteger index = [_dataArray indexOfObject:songName];
if(index==_dataArray.count){
index=0;
}else{
index ++;
}
songName=_dataArray[index];
_nameLabel.text=songName;
NSURL * url = [NSURL fileURLWithPath:[[NSBundle mainBundle]pathForResource: songName ofType:@"mp3" ]];
if([_avPlayer isPlaying]){
[_avPlayer stop];
_avPlayer=nil;
}
_avPlayer=[[AVAudioPlayer alloc]initWithContentsOfURL:url error:nil];
_avPlayer.delegate=self;
[_avPlayer prepareToPlay];
[_avPlayer play];
}
- (IBAction)stopBtn:(id)sender {
if([_avPlayer isPlaying]){
[_avPlayer stop];
}
}
#pragma mark - AVAudioPlayer
-(void)audioPlayerDidFinishPlaying:(AVAudioPlayer *)player successfully:(BOOL)flag{
if([_avPlayer isPlaying]){
[_avPlayer stop];
_avPlayer=nil;
}
NSInteger index = [_dataArray indexOfObject:songName];
if(index==_dataArray.count){
index=0;
}else{
index ++;
}
songName=_dataArray[index];
_nameLabel.text=songName;
NSURL * url = [NSURL fileURLWithPath:[[NSBundle mainBundle]pathForResource: songName ofType:@"mp3" ]];
_avPlayer=[[AVAudioPlayer alloc]initWithContentsOfURL:url error:nil];
_avPlayer.delegate=self;
[_avPlayer prepareToPlay];
[self playBtn:nil];
}
@end