基于AVPlayer
    使用方法：
    在VC中
    #import "MJPlayerView.h"

    然后在属性中添加
    @property (nonatomic ,strong) AVPlayer *player;
    @property (nonatomic ,strong) AVPlayerItem *playerItem;
    @property (nonatomic ,strong)  MJPlayerView *playerView1;

    在viewDidLoad中初始化
    self.playerView1 = [[MJPlayerView alloc]initWithFrame:CGRectMake(0, 0, kMainScreen_Width, kMainScreen_Height/2)];
        [self.view addSubview:self.playerView1];
        self.playerView1.mjPlayerViewDelegate = self;
        [self.playerView1 initMJPlayer:@"http://baobab.wdjcdn.com/1451897812703c.mp4"];
        [self.playerView1 StartPlay];

    实现代理
    -(void)fullScreenOrShrinkScreenDelegate:(UIButton *)sender
    {
        if (sender.selected) {
            [self.navigationController setNavigationBarHidden:YES];
            [[UIDevice currentDevice] setValue:@(UIInterfaceOrientationLandscapeLeft) forKey:@"orientation"];
            self.playerView1.frame = CGRectMake(0, 0,kMainScreen_Width ,kMainScreen_Height );
        }else
        {
            [self.navigationController setNavigationBarHidden:NO];
            self.playerView1.frame = CGRectMake(0, 0,kMainScreen_Height , kMainScreen_Width/2);
            [[UIDevice currentDevice] setValue:@(UIInterfaceOrientationPortrait) forKey:@"orientation"];
        }
        [UIViewController attemptRotationToDeviceOrientation];

    }