爲什麼accelX總是等於零？

Question

在我的應用程序中，當我存檔（產品 - >存檔）的份額獲得.api然後去itunes並安裝在我的iPhone我有設備控制檯中注意accelX總是等於零爲什麼？

注意，如果我在Xcode點擊播放一切工作正常

這是我的代碼：

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

CGSize winSize = [CCDirector sharedDirector].winSize; 
    static float accelX = 0; 
    #define kFilteringFactor 0.1 
    #define kRestAccelX 0.6 
    #define kShipMaxPointsPerSec (winSize.height*0.5) 
    #define kMaxDiffX 0.2 
    UIAccelerationValue rollingX; 

rollingX = (acceleration.x * kFilteringFactor) + 
    (rollingX * (1.0 - kFilteringFactor));  

accelX = acceleration.x - rollingX; 
NSLog(@"accelX :%f",accelX); 


float accelDiffX = kRestAccelX - ABS(accelX); 
float accelFractionX = accelDiffX/kMaxDiffX; 
float pointsPerSecX = kShipMaxPointsPerSec * accelFractionX; 

_shipPointsPerSecY = pointsPerSecX; 

} 

Answer 1

的解決辦法是更換：

UIAccelerationValue rollingX; 

通過

UIAccelerationValue rollingX = 0;