iOS-视频全屏逻辑

需求：视频小窗全屏切换

效果1：状态栏不转屏 （大多数App使用）
效果2：状态栏转屏

实现：

一、状态栏不转屏

videoDemo1.gif

试想一下：视频小窗下面有简介、评论列表、剧集推荐……整个界面转屏？？别闹了
看上面效果图就能想到一个思路：通过检测设备方向，改变视频父视图（videoView）的大小和方向。
实现：

1.检测设备方向

       [[UIDevice currentDevice] beginGeneratingDeviceOrientationNotifications];
       [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(orientationChanged:) name:UIDeviceOrientationDidChangeNotification object:[UIDevice currentDevice]];

2.实现通知方法

- (void)orientationChanged:(NSNotification *)notify{
    
    UIDevice *device = notify.object;
    switch (device.orientation) {
            
        case UIDeviceOrientationLandscapeLeft:
        {
            AXLog(@"屏幕向左平躺");
            if (self.player.isFullScreen) {
                // 如果已全屏，不做任何处理
            }else{
                self.player.isFullScreen = YES;
            }
        }
            
            break;
            
        case UIDeviceOrientationPortrait:
        {
            AXLog(@"屏幕直立");
            if (self.player.isFullScreen) {
                self.player.isFullScreen = NO;
                
            }else{ // 如果已小窗，不做任何处理
            }
        }
            break;
            
        default:
            NSLog(@"无法辨认");
            break;
    }
    
}

3.再来看看 self.player.isFullScreen = NO/YES;起到什么作用呢？

- (void)setIsFullScreen:(BOOL)isFullScreen{
    _isFullScreen = isFullScreen;
    // 更改全屏按钮状态
    self.bottomBar.changeScreenBtn.selected = isFullScreen;
    // 根据是否全屏更改底部工具条的布局
    self.bottomBar.isFullScreenUpdate = isFullScreen;
    
    // 开始转屏
    if (self.isFullScreen) {
        [self beginEnterFullScreen];
    }else{
        [self beginOutFullScreen];
    }
    // 告诉使用此videoPlayer的控制器，进而做一些额外的操作，可忽略
    if ([self.delegate respondsToSelector:@selector(videoPlayer:didChangePlayerFullScreenState:)]) {
        [self.delegate videoPlayer:self didChangePlayerFullScreenState:self.isFullScreen];
    }
    
}

#pragma mark - 转屏处理逻辑

- (void)beginEnterFullScreen{
    [UIView animateWithDuration:0.2 animations:^{
        self.playerView.frame = CGRectMake(0, 0, kScreenHeight, kScreenWidth);
        self.playerView.center = CGPointMake(kScreenWidth/2, kScreenHeight/2);
        CGAffineTransform rotate = CGAffineTransformMakeRotation(M_PI/2);
        
        self.playerView.transform = rotate;
        
        
    } completion:^(BOOL finished) {
        
    }];
}

- (void)beginOutFullScreen{
    
    [UIView animateWithDuration:0.2 animations:^{
        self.playerView.transform = CGAffineTransformIdentity;
        self.playerView.frame = CGRectMake(0, 0, kScreenWidth, kVideoViewHeight);
    } completion:^(BOOL finished) {
        
    }];
    
}

// 其实就是一个 view 的 frame + transform 的 animation  超easy

4.当你destroy播放器的时候，别忘了

    [[UIDevice currentDevice] endGeneratingDeviceOrientationNotifications];
    
    [NSNotificationCenter removeAllObserverForObj:self];

二、状态栏转屏

NSInvocation 不了解的话，可以补充下Rutime知识。

- (void)viewWillLayoutSubviews
{
    [self shouldRotateToOrientation:(UIDeviceOrientation)[UIApplication sharedApplication].statusBarOrientation];
}

- (void)changeScreenAction
{
    if ([[UIDevice currentDevice] respondsToSelector:@selector(setOrientation:)])
    {
        NSNumber *num = [[NSNumber alloc] initWithInt:(_isFullScreen?UIInterfaceOrientationLandscapeRight:UIInterfaceOrientationPortrait)];
        [[UIDevice currentDevice] performSelector:@selector(setOrientation:) withObject:(id)num];
        [UIViewController attemptRotationToDeviceOrientation];
    }
    SEL selector=NSSelectorFromString(@"setOrientation:");
    NSInvocation *invocation =[NSInvocation invocationWithMethodSignature:[UIDevice instanceMethodSignatureForSelector:selector]];
    [invocation setSelector:selector];
    [invocation setTarget:[UIDevice currentDevice]];
    int val = _isFullScreen?UIInterfaceOrientationLandscapeRight:UIInterfaceOrientationPortrait;
    [invocation setArgument:&val atIndex:2];
    [invocation invoke];
}

#pragma mark - 转屏处理逻辑

-(void)shouldRotateToOrientation:(UIDeviceOrientation)orientation {
    
    if (orientation == UIDeviceOrientationPortrait ||orientation == UIDeviceOrientationPortraitUpsideDown) {
        
        // 竖屏
        _isFullScreen = NO;
        _playerView.frame = PlayerHalfFrame;
    }
    
    else {
        
        // 横屏
        CGFloat width = [UIScreen mainScreen].bounds.size.width;
        CGFloat height = [UIScreen mainScreen].bounds.size.height;
        if (width < height)
        {
            CGFloat tmp = width;
            width = height;
            height = tmp;
        }
        _isFullScreen = YES;
        _playerView.frame = CGRectMake(0, 0, width, height);
    }
}