时间:2021-03-15 09:49:04 | 栏目:iOS代码 | 点击:次
众所周知, 微信中的摇一摇功能: 搜索人/歌曲/电视,同样在一些其他类APP中也有一个摇一摇签到, 摇一摇随机选号等功能,下面以微信摇一摇功能来介绍实现原理.
对于摇一摇功能, 在iOS中系统默认为我们提供了摇一摇的功能检测API. iOS 中既然已经提供了接口, 我们直接调用就好了.
#import <QuartzCore/QuartzCore.h> #import <AudioToolbox/AudioToolbox.h>
实现原理
1. 监听摇一摇方法
// 摇一摇开始 - (void)motionBegan:(UIEventSubtype)motion withEvent:(nullable UIEvent *)event NS_AVAILABLE_IOS(3_0); // 摇一摇结束 - (void)motionEnded:(UIEventSubtype)motion withEvent:(nullable UIEvent *)event NS_AVAILABLE_IOS(3_0); // 摇一摇取消 - (void)motionCancelled:(UIEventSubtype)motion withEvent:(nullable UIEvent *)event NS_AVAILABLE_IOS(3_0);
2. 解决摇一摇失效的情况.
ps: 使用 Xcode6.x 后创建的项目,仅仅实现第一步监听就可以实现,没有遇到这种问题.
- (BOOL)canBecomeFirstResponder { return YES; }
3. 摇一摇阶段需要震动及声音.
// 摇动开始 - (void)motionBegan:(UIEventSubtype)motion withEvent:(UIEvent *)event { AudioServicesPlaySystemSound(kSystemSoundID_Vibrate); }
// 摇动结束 - (void)motionEnded:(UIEventSubtype)motion withEvent:(UIEvent *)event { if (motion ==UIEventSubtypeMotionShake ) { // 1.添加摇动动画 // 见第四点, 推荐第四点的方法二 // 2.设置播放音效 SystemSoundID soundID; NSString *path = [[NSBundle mainBundle ] pathForResource:@"shake_sound_male" ofType:@"wav"]; AudioServicesCreateSystemSoundID((__bridge CFURLRef)[NSURL fileURLWithPath:path], &soundID); // 添加摇动声音 AudioServicesPlaySystemSound (soundID); // 3.设置震动 AudioServicesPlaySystemSound(kSystemSoundID_Vibrate); } }
4. 摇一摇阶段需要动画效果.
微信的摇一摇功能是先在视图上放一个摇后要显示的图片:手拿手机的图片, 这个图片就是上下两半拼在一起给人一种一张图片的感觉;当检测到摇一摇 捕捉到晃动事件后,上下两张图片分别上下做一个动画移动(上面的一半往上移,下面的往下移),在completion 里面再移回来.
这里有两种方法:
方法一: 抽出来添加动画效果的方法, 在摇一摇结束方法里添加这个方法.
- (void)addAnimations { // 让imgup上下移动 CABasicAnimation *translation2 = [CABasicAnimation animationWithKeyPath:@"position"]; translation2.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut]; translation2.fromValue = [NSValue valueWithCGPoint:CGPointMake(160, 115)]; translation2.toValue = [NSValue valueWithCGPoint:CGPointMake(160, 40)]; translation2.duration = 0.5; translation2.repeatCount = 1; translation2.autoreverses = YES; // 让imagdown上下移动 CABasicAnimation *translation = [CABasicAnimation animationWithKeyPath:@"position"]; translation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut]; translation.fromValue = [NSValue valueWithCGPoint:CGPointMake(160, 345)]; translation.toValue = [NSValue valueWithCGPoint:CGPointMake(160, 420)]; translation.duration = 0.5; translation.repeatCount = 1; translation.autoreverses = YES; [self.imgDown.layer addAnimation:translation forKey:@"translation"]; [self.imgUp.layer addAnimation:translation2 forKey:@"translation2"]; }
方法二. 在摇一摇开始和结束里添加摇动动画效果及菊花效果
/** * 摇动开始 */ - (void)motionBegan:(UIEventSubtype)motion withEvent:(UIEvent *)event { NSLog(@"开始摇了"); // 菊花显示并开始转动 self.aiLoad.hidden = NO; [self.aiLoad startAnimating]; AudioServicesPlaySystemSound(kSystemSoundID_Vibrate); CGFloat offset = self.bgImgView.height * 0.5; CGFloat duration = 0.4; [UIView animateWithDuration:duration animations:^{ self.imgUp.y -= offset; self.imgDown.y += offset; }]; } /** * 摇动结束 */ - (void)motionEnded:(UIEventSubtype)motion withEvent:(UIEvent *)event { NSLog(@"摇动结束"); // 不是摇一摇事件则返回 if (motion != UIEventSubtypeMotionShake) return; // 1.添加摇动动画 CGFloat offset = self.bgImgView.height * 0.5; CGFloat duration = 0.4; [UIView animateWithDuration:duration animations:^{ self.imgUp.y += offset; self.imgDown.y -= offset; }]; // 菊花暂停转动并隐藏 [self.aiLoad stopAnimating]; self.aiLoad.hidden = YES; }
当然也有使用摇一摇做其他功能的,可以在当结束摇动时,就发送一个网络请求作相关操作即可。