iOS 基于AVPlayer的简易播放器

2019-07-29 本文已影响0人邓布利多教授

简单介绍一下，AVPlayer是基于AVFoundation框架的一个类，很接近底层，灵活性强，方便自定义各种需求，使用之前需要先导入#import <AVKit/AVKit.h>

这个简易播放器非常简单，是我拿了练手玩的，功能只包括播放、暂停、滑动播放、显示缓冲进度。

下面开始解释实现思路，很简单的
1、我想要一个可以播放url地址的播放器
2、这个播放器，我需要显示网络状态
3、除了播放、暂停按钮、可拖拽的进度条、显示当前播放时间和视频总时长以外，我还想要一个显示缓冲的进度条

好，我的需求就这么简单，我就是想要自己写一个这样的播放器，至于其他的更复杂更好的用户体验的功能，暂时不考虑。目标明确了，开工。

1、工具条

这个工具条上面要包括：
1、播放（暂停）按钮的UIButton
2、可以拖拽的进度条UISlider
3、显示当前播放时间和显示视频总时长的UILabel
4、显示缓冲进度的UIProgressView

首先创建一个UIView，生成.h和.m文件，开始添加我需要的这些东西，开始之前我考虑到播放和暂停按钮我是用的一个Button，所以在切换状态的时候，我还要对应着改变按钮的icon，所以我为了方便，在工具条这个View里添加了一个Delegate，为了改变icon的同时，把状态传递出去，所以.h文件我这样写，代码如下：

#import <UIKit/UIKit.h>

NS_ASSUME_NONNULL_BEGIN

@protocol VideoPlayerToolsViewDelegate <NSObject>

-(void)playButtonWithStates:(BOOL)state;

@end

@interface VideoPlayerToolsView : UIView

@property (nonatomic, strong) UIButton *bCheck;//播放暂停按钮
@property (nonatomic, strong) UISlider *progressSr;//进度条
@property (nonatomic, strong) UIProgressView *bufferPV;//缓冲条
@property (nonatomic, strong) UILabel *lTime;//时间进度和总时长

@property (nonatomic, weak) id<VideoPlayerToolsViewDelegate> delegate;

@end

NS_ASSUME_NONNULL_END

.m文件

#import "VideoPlayerToolsView.h"

@interface VideoPlayerToolsView ()

@end

@implementation VideoPlayerToolsView

-(instancetype)initWithFrame:(CGRect)frame{
    
    self = [super initWithFrame:frame];
    if (self) {
        self.backgroundColor = [UIColor colorWithWhite:0 alpha:0.5];
        [self createUI];//创建UI
    }
    return self;
    
}

#pragma mark - 创建UI
-(void)createUI{
    [self addSubview:self.bCheck];//开始暂停按钮
    [self addSubview:self.bufferPV];//缓冲条
    [self addSubview:self.progressSr];//创建进度条
    [self addSubview:self.lTime];//视频时间
}

#pragma mark - 视频时间
-(UILabel *)lTime{
    
    if (!_lTime) {
        _lTime = [UILabel new];
        _lTime.frame = CGRectMake(CGRectGetMaxX(_progressSr.frame) + 20, 0, self.frame.size.width - CGRectGetWidth(_progressSr.frame) - 40 - CGRectGetWidth(_bCheck.frame), self.frame.size.height);
        _lTime.text = @"00:00/00:00";
        _lTime.textColor = [UIColor whiteColor];
        _lTime.textAlignment = NSTextAlignmentCenter;
        _lTime.font = [UIFont systemFontOfSize:12];
        _lTime.adjustsFontSizeToFitWidth = YES;
    }
    return _lTime;
    
}

#pragma mark - 创建进度条
-(UISlider *)progressSr{
    
    if (!_progressSr) {
        _progressSr = [UISlider new];
        _progressSr.frame = CGRectMake(CGRectGetMinX(_bufferPV.frame) - 2, CGRectGetMidY(_bufferPV.frame) - 10, CGRectGetWidth(_bufferPV.frame) - 4, 20);
        _progressSr.maximumTrackTintColor = [UIColor clearColor];
        _progressSr.minimumTrackTintColor = [UIColor whiteColor];
        [_progressSr setThumbImage:[UIImage imageNamed:@"point"] forState:0];
    }
    return _progressSr;
    
}

#pragma mark - 缓冲条
-(UIProgressView *)bufferPV{
    
    if (!_bufferPV) {
        _bufferPV = [UIProgressView new];
        _bufferPV.frame = CGRectMake(CGRectGetMaxX(_bCheck.frame) + 20, CGRectGetMidY(_bCheck.frame) - 2, 200, 4);
        _bufferPV.trackTintColor = [UIColor grayColor];
        _bufferPV.progressTintColor = [UIColor cyanColor];
    }
    return _bufferPV;
    
}

#pragma mark - 开始暂停按钮
-(UIButton *)bCheck{
    
    if (!_bCheck) {
        _bCheck = [UIButton new];
        _bCheck.frame = CGRectMake(0, 0, self.frame.size.height, self.frame.size.height);
        [_bCheck setImage:[UIImage imageNamed:@"pause"] forState:0];
        [_bCheck addTarget:self action:@selector(btnCheckSelect:) forControlEvents:UIControlEventTouchUpInside];
    }
    return _bCheck;
    
}

-(void)btnCheckSelect:(UIButton *)sender{
    
    sender.selected = !sender.isSelected;
    
    if (sender.selected) {
        [_bCheck setImage:[UIImage imageNamed:@"play"] forState:0];
    }else{
        [_bCheck setImage:[UIImage imageNamed:@"pause"] forState:0];
    }
    
    if ([_delegate respondsToSelector:@selector(playButtonWithStates:)]) {
        [_delegate playButtonWithStates:sender.selected];
    }
    
}

@end

随便把这个工具条加载到任一一个页面看下效果，没错，目前看来就是我要的样子，先放着，后面再调用。

2、网络状态监听器

这个网络监听器是网上找到的，本来想把原文地址留下来的，结果忘记了，在这里表示抱歉，至于这个工具怎么实现的，实话实说，我看不懂，我就知道它就是我想要的东西，是不是很尴尬……那也没办法，能力有限！这个工具的使用我单独拿出去写了个文章，这里不再重复黏贴代码了。

3、AVPlayer播放器

这里是重头戏了，首先，要知道AVPlayer是怎么用的。
AVPlayer是个播放器，但是呢，它又不能直接播放视频，它需要和AVPlayerLayer配合着使用，并且需要把AVPlayerLayer添加到视图的layer上才行，比如：[self.layer addSublayer:self.playerLayer];。

AVPlayer加载视频地址的方式是什么呢？我得需要知道，查看api，control+command+鼠标左键，进去瞅瞅，发现系统有提供以下几种方式：

+ (instancetype)playerWithURL:(NSURL *)URL;
+ (instancetype)playerWithPlayerItem:(nullable AVPlayerItem *)item;
- (instancetype)initWithURL:(NSURL *)URL;
- (instancetype)initWithPlayerItem:(nullable AVPlayerItem *)item;

那么问题来了，上面的四种方法里面有两个是用AVPlayerItem初始化的，这个是什么东西。再继续看api，什么东西啊，乱七八糟一大推，于是乎，不看了，看看前辈们是咋玩的，后来发现，前辈们用了一个叫做：replaceCurrentItemWithPlayerItem:的方法给AVPlayer添加播放地址，从字面上的意思我的理解是：用PlayerItem替换当前的item？？
完整代码是这样写的：

AVPlayerItem *item = [AVPlayerItem playerItemWithURL:[NSURL URLWithString:@"视频地址"]];
[self.player replaceCurrentItemWithPlayerItem:item];

然后AVPlayer怎么添加到AVPlayerLayer上呢？代码如下：

_playerLayer = [AVPlayerLayer playerLayerWithPlayer:self.player];

这里要说明一下，AVPlayerLayer是需要设置frame的。

好，这里假设各个控件的初始化啊布局什么的都完事了，接下来要考虑的是控件之间相互关联显示的问题了。

1、我要先让视频播放出来再说，别的先不管，拿到地址之后，先让self.player调一下播放方法，然后监听网络，再然后用视频地址初始化一个AVPlayerItem，最后用这个AVPlayerItem播放视频，好像没毛病，就这么干了。
2、视频成功播放出来之后，我得要显示视频总时长和当前播放时间进度，方法如下：

NSTimeInterval totalTime = CMTimeGetSeconds(self.player.currentItem.duration);//总时长
NSTimeInterval currentTime = CMTimeGetSeconds(self.player.currentTime);//当前时间进度

3、经过了七七四十九天的调整，时间终于显示正确了，接下来需要显示缓冲进度了，这里就需要用的KVO来对初始化self.player的时候用到的那个AVPlayerItem的属性进行监听了，我就说这个东西肯定是有用的嘛，不然为啥那么多人都用这玩意儿。
4、又经过了一个七七四十九天的调整，通过网络监听工具看着的网络变化，缓冲条好像也显示正确了，最后到了进度条的显示了……

春夏秋冬，年复一年，日复一日，不知道经过了多少个岁月……

5、上代码吧，先声明一下，代码里面肯定是包含了一些经过自己的加工让它改头换面的内容，大家都来自五湖四海，组到一起也是缘分，代码如下：
.h文件

#import <UIKit/UIKit.h>

NS_ASSUME_NONNULL_BEGIN

@interface VideoPlayerContainerView : UIView

@property (nonatomic, strong) NSString *urlVideo;

-(void)dealloc;

@end

NS_ASSUME_NONNULL_END

.m文件

#import "VideoPlayerContainerView.h"
#import <AVKit/AVKit.h>

#import "NetworkSpeedMonitor.h"
#import "VideoPlayerToolsView.h"

@interface VideoPlayerContainerView ()<VideoPlayerToolsViewDelegate>

@property (nonatomic, strong) AVPlayer *player;
@property (nonatomic, strong) AVPlayerLayer *playerLayer;
@property (nonatomic, strong) NetworkSpeedMonitor *speedMonitor;//网速监听
@property (nonatomic, strong) UILabel *speedTextLabel;//显示网速Label
@property (nonatomic, strong) VideoPlayerToolsView *vpToolsView;//工具条

@property (nonatomic, strong) id playbackObserver;
@property (nonatomic) BOOL buffered;//是否缓冲完毕

@end

@implementation VideoPlayerContainerView

//设置播放地址
-(void)setUrlVideo:(NSString *)urlVideo{
    
    [self.player seekToTime:CMTimeMakeWithSeconds(0, NSEC_PER_SEC) toleranceBefore:kCMTimeZero toleranceAfter:kCMTimeZero];
    [self.player play];//开始播放视频
    
    [self.speedMonitor startNetworkSpeedMonitor];//开始监听网速
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(networkSpeedChanged:) name:NetworkDownloadSpeedNotificationKey object:nil];
    
    AVPlayerItem *item = [AVPlayerItem playerItemWithURL:[NSURL URLWithString:urlVideo]];
    [self vpc_addObserverToPlayerItem:item];
    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
        [self.player replaceCurrentItemWithPlayerItem:item];
        [self vpc_playerItemAddNotification];
    });
    
}

-(instancetype)initWithFrame:(CGRect)frame{
    
    self = [super initWithFrame:frame];
    if (self) {
        
        self.backgroundColor = [UIColor groupTableViewBackgroundColor];
        [self.layer addSublayer:self.playerLayer];
        [self addSubview:self.speedTextLabel];
        [self addSubview:self.vpToolsView];
        
    }
    return self;
    
}

- (void)networkSpeedChanged:(NSNotification *)sender {
    NSString *downloadSpped = [sender.userInfo objectForKey:NetworkSpeedNotificationKey];
    self.speedTextLabel.text = downloadSpped;
}

#pragma mark - 工具条
-(VideoPlayerToolsView *)vpToolsView{
    
    if (!_vpToolsView) {
        
        _vpToolsView = [[VideoPlayerToolsView alloc]initWithFrame:CGRectMake(0, CGRectGetHeight(self.frame) - 40, CGRectGetWidth(self.frame), 40)];
        _vpToolsView.delegate = self;
        
        [_vpToolsView.progressSr addTarget:self action:@selector(vpc_sliderTouchBegin:) forControlEvents:UIControlEventTouchDown];
        [_vpToolsView.progressSr addTarget:self action:@selector(vpc_sliderValueChanged:) forControlEvents:UIControlEventValueChanged];
        [_vpToolsView.progressSr addTarget:self action:@selector(vpc_sliderTouchEnd:) forControlEvents:UIControlEventTouchUpInside];
    }
    return _vpToolsView;
    
}

-(void)playButtonWithStates:(BOOL)state{
    
    if (state) {
        [self.player pause];
    }else{
        [self.player play];
    }
    
}

- (void)vpc_sliderTouchBegin:(UISlider *)sender {
    [self.player pause];
}

- (void)vpc_sliderValueChanged:(UISlider *)sender {
    
    NSTimeInterval currentTime = CMTimeGetSeconds(self.player.currentItem.duration) * _vpToolsView.progressSr.value;
    NSInteger currentMin = currentTime / 60;
    NSInteger currentSec = (NSInteger)currentTime % 60;
    _vpToolsView.lTime.text = [NSString stringWithFormat:@"%02ld:%02ld",currentMin,currentSec];
    
}

- (void)vpc_sliderTouchEnd:(UISlider *)sender {
    
    NSTimeInterval slideTime = CMTimeGetSeconds(self.player.currentItem.duration) * _vpToolsView.progressSr.value;
    if (slideTime == CMTimeGetSeconds(self.player.currentItem.duration)) {
        slideTime -= 0.5;
    }
    [self.player seekToTime:CMTimeMakeWithSeconds(slideTime, NSEC_PER_SEC) toleranceBefore:kCMTimeZero toleranceAfter:kCMTimeZero];
    [self.player play];
    
}

#pragma mark - 网速监听器
- (NetworkSpeedMonitor *)speedMonitor {
    if (!_speedMonitor) {
        _speedMonitor = [[NetworkSpeedMonitor alloc] init];
    }
    return _speedMonitor;
}

#pragma mark - 显示网速Label
- (UILabel *)speedTextLabel {
    
    if (!_speedTextLabel) {
        _speedTextLabel = [UILabel new];
        _speedTextLabel.frame = CGRectMake(0, 0, self.frame.size.width, 20);
        _speedTextLabel.textColor = [UIColor whiteColor];
        _speedTextLabel.font = [UIFont systemFontOfSize:12.0];
        _speedTextLabel.textAlignment = NSTextAlignmentCenter;
        _speedTextLabel.backgroundColor = [UIColor colorWithWhite:0 alpha:0.5];
    }
    return _speedTextLabel;
    
}

#pragma mark - AVPlayer
-(AVPlayer *)player{
    
    if (!_player) {
        _player = [[AVPlayer alloc] init];
        __weak typeof(self) weakSelf = self;
        // 每秒回调一次
        self.playbackObserver = [_player addPeriodicTimeObserverForInterval:CMTimeMake(1, 1) queue:NULL usingBlock:^(CMTime time) {
            [weakSelf vpc_setTimeLabel];
            NSTimeInterval totalTime = CMTimeGetSeconds(weakSelf.player.currentItem.duration);//总时长
            NSTimeInterval currentTime = time.value / time.timescale;//当前时间进度
            weakSelf.vpToolsView.progressSr.value = currentTime / totalTime;
        }];
    }
    return _player;
    
}

#pragma mark - AVPlayerLayer
-(AVPlayerLayer *)playerLayer{
    
    if (!_playerLayer) {
        _playerLayer = [AVPlayerLayer playerLayerWithPlayer:self.player];
        _playerLayer.frame = CGRectMake(0, 0, self.frame.size.width, self.frame.size.height);
    }
    return _playerLayer;
    
}

#pragma mark ---------华丽的分割线---------

#pragma mark - lTime
- (void)vpc_setTimeLabel {
    
    NSTimeInterval totalTime = CMTimeGetSeconds(self.player.currentItem.duration);//总时长
    NSTimeInterval currentTime = CMTimeGetSeconds(self.player.currentTime);//当前时间进度
    
    // 切换视频源时totalTime/currentTime的值会出现nan导致时间错乱
    if (!(totalTime >= 0) || !(currentTime >= 0)) {
        totalTime = 0;
        currentTime = 0;
    }
    
    NSInteger totalMin = totalTime / 60;
    NSInteger totalSec = (NSInteger)totalTime % 60;
    NSString *totalTimeStr = [NSString stringWithFormat:@"%02ld:%02ld",totalMin,totalSec];
    
    NSInteger currentMin = currentTime / 60;
    NSInteger currentSec = (NSInteger)currentTime % 60;
    NSString *currentTimeStr = [NSString stringWithFormat:@"%02ld:%02ld",currentMin,currentSec];
    
    _vpToolsView.lTime.text = [NSString stringWithFormat:@"%@/%@",currentTimeStr,totalTimeStr];
    
}

#pragma mark - 观察者
- (void)vpc_playerItemAddNotification {
    // 播放完成通知
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(vpc_playbackFinished:) name:AVPlayerItemDidPlayToEndTimeNotification object:self.player.currentItem];
}

-(void)vpc_playbackFinished:(NSNotification *)noti{
    [self.player pause];
}

- (void)vpc_addObserverToPlayerItem:(AVPlayerItem *)playerItem {
    // 监听播放状态
    [playerItem addObserver:self forKeyPath:@"status" options:NSKeyValueObservingOptionNew context:nil];
    // 监听缓冲进度
    [playerItem addObserver:self forKeyPath:@"loadedTimeRanges" options:NSKeyValueObservingOptionNew context:nil];
}

- (void)vpc_playerItemRemoveNotification {
    [[NSNotificationCenter defaultCenter] removeObserver:self name:AVPlayerItemDidPlayToEndTimeNotification object:self.player.currentItem];
}

- (void)vpc_playerItemRemoveObserver {
    [self.player.currentItem removeObserver:self forKeyPath:@"status"];
    [self.player.currentItem removeObserver:self forKeyPath:@"loadedTimeRanges"];
}

- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary<NSString *,id> *)change context:(void *)context {
    if ([keyPath isEqualToString:@"status"]) {
        AVPlayerStatus status= [[change objectForKey:@"new"] intValue];
        if (status == AVPlayerStatusReadyToPlay) {
            [self vpc_setTimeLabel];
        }
    } else if ([keyPath isEqualToString:@"loadedTimeRanges"]) {
        NSArray *array = self.player.currentItem.loadedTimeRanges;
        CMTimeRange timeRange = [array.firstObject CMTimeRangeValue];//本次缓冲时间范围
        NSTimeInterval startSeconds = CMTimeGetSeconds(timeRange.start);//本次缓冲起始时间
        NSTimeInterval durationSeconds = CMTimeGetSeconds(timeRange.duration);//缓冲时间
        NSTimeInterval totalBuffer = startSeconds + durationSeconds;//缓冲总长度
        float totalTime = CMTimeGetSeconds(self.player.currentItem.duration);//视频总长度
        float progress = totalBuffer/totalTime;//缓冲进度
        NSLog(@"progress = %lf",progress);
        
        //如果缓冲完了，拖动进度条不需要重新显示缓冲条
        if (!self.buffered) {
            if (progress == 1.0) {
                self.buffered = YES;
            }
            [self.vpToolsView.bufferPV setProgress:progress];
        }
        NSLog(@"yon = %@",self.buffered ? @"yes" : @"no");
    }
}

- (void)dealloc {
    
    [self.speedMonitor stopNetworkSpeedMonitor];
    [[NSNotificationCenter defaultCenter] removeObserver:self name:NetworkDownloadSpeedNotificationKey object:nil];
    
    [self.player removeTimeObserver:self.playbackObserver];
    [self vpc_playerItemRemoveObserver];
    [self.player replaceCurrentItemWithPlayerItem:nil];
    [[NSNotificationCenter defaultCenter] removeObserver:self];
    
}

@end

4、整合

最后全部封装完了之后，调用的时候，只需要引入头文件#import "VideoPlayerContainerView.h"，在需要用的地方，直接声明，传值就ok了

VideoPlayerContainerView *vpcView = [[VideoPlayerContainerView alloc]initWithFrame:CGRectMake(0, 100, [UIScreen mainScreen].bounds.size.width, 200)];
[self.view addSubview:vpcView];
    
vpcView.urlVideo = @"https://www.apple.com/105/media/cn/researchkit/2016/a63aa7d4_e6fd_483f_a59d_d962016c8093/films/carekit/researchkit-carekit-cn-20160321_848x480.mp4";

效果图.gif

iOS 基于AVPlayer的简易播放器

1、工具条

2、网络状态监听器

3、AVPlayer播放器

4、整合

5、全剧终

猜你喜欢

热点阅读