如何在iOS中实现大力摇一摇？

Posted 2023-03-10

【中文标题】如何在iOS中实现大力摇一摇？

【英文标题】：How to achieve vigorous Shake in iOS?

【发布时间】：2012-09-03 10:25:12

【问题描述】：

我在 ios 中使用摇晃功能。它与下面的代码工作正常。但是当我进行剧烈摇晃时，它检测到摇晃并在一秒钟内调用这条线if (histeresisExcited && !L0AccelerationIsShaking(self.lastAcceleration, acceleration, 0.2)) histeresisExcited = NO;，尽管我一直在摇晃。

如何实现剧烈摇晃？

我在这里做错了什么？

// Ensures the shake is strong enough on at least two axes before declaring it a shake.
// "Strong enough" means "greater than a client-supplied threshold" in G's.
static BOOL L0AccelerationIsShaking(UIAcceleration* last, UIAcceleration* current, double threshold) 
    double
            deltaX = fabs(last.x - current.x),
            deltaY = fabs(last.y - current.y),
            deltaZ = fabs(last.z - current.z);

    return
            (deltaX > threshold && deltaY > threshold) ||
            (deltaX > threshold && deltaZ > threshold) ||
            (deltaY > threshold && deltaZ > threshold);


@interface L0AppDelegate : NSObject <UIApplicationDelegate> 
    BOOL histeresisExcited;
    UIAcceleration* lastAcceleration;


@property(retain) UIAcceleration* lastAcceleration;

@end

实施

@implementation L0AppDelegate

- (void)applicationDidFinishLaunching:(UIApplication *)application 
     [UIAccelerometer sharedAccelerometer].delegate = self;


- (void) accelerometer:(UIAccelerometer *)accelerometer didAccelerate:(UIAcceleration *)acceleration 

    if (self.lastAcceleration) 
            if (!histeresisExcited && L0AccelerationIsShaking(self.lastAcceleration, acceleration, 0.7)) 
                    histeresisExcited = YES;

                    /* SHAKE DETECTED. DOING SOME DATABASE OPERATIONS HERE. */

             else if (histeresisExcited && !L0AccelerationIsShaking(self.lastAcceleration, acceleration, 0.2)) 
                    histeresisExcited = NO;

                 /* SHAKE STOPPED. CALLING A VIEW CONTROLLER TO DISPLAY THE CONTENTS GOT FROM THE DATABASE*/
            
    

    self.lastAcceleration = acceleration;
 

// and proper @synthesize and -dealloc boilerplate code

 @end

感谢您的帮助。

【参考方案1】：

通过对我的代码稍作改动，终于得到了答案

更改以下代码

static BOOL L0AccelerationIsShaking(UIAcceleration* last, UIAcceleration* current, double threshold) 
double
        deltaX = fabs(last.x - current.x),
        deltaY = fabs(last.y - current.y),
        deltaZ = fabs(last.z - current.z);

return
        (deltaX > threshold && deltaY > threshold) ||
        (deltaX > threshold && deltaZ > threshold) ||
        (deltaY > threshold && deltaZ > threshold);

到

static BOOL L0AccelerationIsShaking(UIAcceleration* last, UIAcceleration* current, double threshold) 
double
        deltaX = fabs(last.x - current.x),
        deltaY = fabs(last.y - current.y),
        deltaZ = fabs(last.z - current.z);

return
        (deltaX > threshold) ||
        (deltaY > threshold) ||
        (deltaZ > threshold);

像魅力一样工作。

希望对像我这样的人有所帮助。