考虑平移以清除video时的当前时间
这是与平移/可擦除video相关的代码。 当第二次滑动手势具有来自第一次滑动的最后位置的增量时，会出现当前问题。 换句话说，此代码需要考虑video的当前时间以防止跳过。
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func didSwipe(panGR: UIPanGestureRecognizer) { let translation = panGR.translationInView(self.view) var horizontalTranslation = Float(translation.x) let durationInSeconds = Float(CMTimeGetSeconds(self.playerView.player.player.currentItem!.asset.duration)) // Using 275 as the limit for delta along x let translationLimit: Float = 275 let minTranslation: Float = -1 * translationLimit let maxTranslation: Float = translationLimit if horizontalTranslation > maxTranslation { horizontalTranslation = maxTranslation } if horizontalTranslation Float { let result = ((delta - minDelta) * (maxDuration - minDuration) / (maxDelta - minDelta) + minDuration) return result } “`
我将开始时间设置为video长度的一半。 这会在任一方向上产生良好的第一次滑动结果。 它在第二次和随后的滑动中有明显的跳过，因为它不考虑video的当前时间（我认为）。
这是我编写的使用normalize函数的代码，并显示当前速率（以及根据玩家速率改变大小的Play图标：
- (IBAction)handlePanGesture:(UIPanGestureRecognizer *)sender { if (sender.state == UIGestureRecognizerStateBegan) { [self.rateLabel setHidden:FALSE]; [self animatePlayerControl:@"▷" size:1.0]; [UIView animateWithDuration:0.375 animations:^{ (self.playerControlsLabel).alpha = 0.5f; }]; } else if (sender.state == UIGestureRecognizerStateEnded) { [self.rateLabel setHidden:FALSE]; // set to TRUE after testing or remove hiding altogether //[self.delegate setRate:oldRate]; //[self animatePlayerControl:@"□" size:1.0]; //[_ChromaEpsilonGammaAppDelegate.playerViewController setRate:0.0]; //[_ChromaEpsilonGammaAppDelegate.playerViewController stop]; [UIView animateWithDuration:0.375 animations:^{ (self.playerControlsLabel).alpha = 0.0f; }]; } else if (sender.state == UIGestureRecognizerStateChanged){ CGPoint location = [sender locationInView:self]; float nlx = ((location.x / ((CGRectGetMidX(self.frame) / (self.frame.size.width / 2.0)))) / (self.frame.size.width / 2.0)) - 1.0; //float nly = ((location.y / ((CGRectGetMidY(self.view.frame) / (self.view.frame.size.width / 2.0)))) / (self.view.frame.size.width / 2.0)) - 1.0; nlx = nlx * 2.0; [self.delegate setRate:nlx]; if (nlx > 0.0) [self animatePlayerControl:@"▷" size:nlx]; else if (nlx < 0.0) [self animatePlayerControl:@"◁" size:fabs(nlx)]; (self.rateLabel).text = [NSString stringWithFormat:@"%.2f", [self.delegate rate]]; } }
标签设置，可以去任何地方，而不仅仅是drawRect方法：
- (void)drawRect:(CGRect)rect { (self.brightnessLabel).textColor = [UIColor colorWithWhite:1.0 alpha:1.0]; (self.brightnessLabel).font = [UIFont preferredFontForTextStyle:@"Apple Symbol"]; (self.brightnessLabel).textAlignment = NSTextAlignmentCenter; (self.contrastLabel).textColor = [UIColor colorWithWhite:1.0 alpha:1.0]; (self.contrastLabel).font = [UIFont preferredFontForTextStyle:@"Apple Symbol"]; (self.contrastLabel).textAlignment = NSTextAlignmentCenter; _attrsDictionary = @{NSFontAttributeName: [UIFont systemFontOfSize:24.0 weight:UIFontWeightLight]}; }
并且，自动调整播放器图标大小代码：
- (void)animatePlayerControl:(NSString *)labelText size:(float)size { (self.playerControlsLabel).textColor = [UIColor colorWithWhite:1.0 alpha:1.0]; (self.playerControlsLabel).font = [UIFont preferredFontForTextStyle:@"Apple Symbol"]; (self.playerControlsLabel).textAlignment = NSTextAlignmentCenter; NSDictionary *attrsDictionary = @{NSFontAttributeName: [UIFont systemFontOfSize:fabs(48.0 * size) weight:UIFontWeightUltraLight]}; NSAttributedString *attrString = [[NSAttributedString alloc] initWithString:labelText attributes:attrsDictionary]; (self.playerControlsLabel).attributedText = attrString; }
播放器图标只是Apple Symbol字体中的一个字符。