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我正在尝试开发一个应用程序，该应用程序具有类似于“我周围”的位置列表功能，侧面带有小方向箭头。多亏了 Stackoverflow，不同位置的方位和偏移不是问题，并且通过以下教程补偿罗盘滞后做得很好：http: //www.sundh.com/blog/2011/09/stabalize-compass-of-带陀螺仪的iphone/

所有的东西都可以在该 UITableView 中的一个位置正常工作。但是当有多个位置时，箭头不会变得平滑，感觉我的 iPhone 不够快，无法计算这些东西并转动这些多个箭头，但我不知道如何做得更好。

目前我正在尝试这个（没有位置特定的方向偏移）：

  • 我将所有单元格的所有 UIImageViews 保存在一个数组中

  • 当获得一个新的偏航值时，我遍历数组并实现所有图像旋转

    if(motionManager.isDeviceMotionAvailable) {
    // Listen to events from the motionManager
    motionHandler = ^ (CMDeviceMotion *motion, NSError *error) {
    CMAttitude *currentAttitude = motion.attitude;
    float yawValue = currentAttitude.yaw; // Use the yaw value

    // Yaw values are in radians (-180 - 180), here we convert to degrees
    float yawDegrees = CC_RADIANS_TO_DEGREES(yawValue);
    currentYaw = yawDegrees;

    // We add new compass value together with new yaw value
    yawDegrees = newCompassTarget + (yawDegrees - offsetG);

    // Degrees should always be positive
    if(yawDegrees < 0) {
        yawDegrees = yawDegrees + 360;
    }

    compassDif.text = [NSString stringWithFormat:@"Gyro: %f",yawDegrees]; // Debug

    float gyroDegrees = (yawDegrees*radianConst);

    // If there is a new compass value the gyro graphic animates to this position
    if(updateCompass) {
        [self setRotateArrow:gyroDegrees animated:YES];
        [self commitAnimations];
        updateCompass = 0;
    } else {
        [self setRotateArrow:gyroDegrees animated:NO];
        [UIView commitAnimations];
    }
};

和 setRotateArrow:animated 方法：

- (void) setRotateArrow:(float)degrees animated:(BOOL)animated{    
    UIImage *arrowImage = [UIImage imageNamed:@"DirectionArrow.png"];
    for (int i = 0; i<arrowImageViews.count; i++) {
       [(UIImageView *)[arrowImageViews objectAtIndex:i] setImage:arrowImage];


        CGFloat arrowTransform = degrees;

        //Rotate the Arrow
        CGAffineTransform rotate = CGAffineTransformMakeRotation(arrowTransform);

        [(UIImageView *)[arrowImageViews objectAtIndex:i] setTransform:rotate];
    }
}

如果有人知道如何在设备旋转之后平稳地使箭头旋转，我将非常感激。

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