使用iOS上的動畫將UIImageView旋轉180度以上

Question

我試圖通過將移動儀表旋轉180度以上來為其動畫，但它無法正常工作。 我使用CGAffineTransform旋轉儀表，后者使用凈結果進行旋轉。 這意味着使用此功能時，我無法選擇CW或CCW旋轉。 如何修改此代碼以使其旋轉4弧度。 當前，旋轉被轉換為最終結果，從而使旋轉最小。

[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:1.25]; 
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
CGAffineTransform transform = CGAffineTransformMakeRotation(4);
self.meter.transform = transform;
[UIView commitAnimations];

編輯：從答案我設法做到這一點

 [UIView animateWithDuration:1.5 animations:^{
    CABasicAnimation *fullRotation;
    fullRotation = [CABasicAnimation animationWithKeyPath:@"transform.rotation"];
    fullRotation.fromValue = [NSNumber numberWithFloat:0];
    fullRotation.toValue = [NSNumber numberWithFloat:((330*M_PI)/180)];
    fullRotation.duration = 2.0f;
    fullRotation.repeatCount = 1;
    fullRotation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
    fullRotation.fillMode = kCAFillModeForwards;
    fullRotation.removedOnCompletion = NO;

    // add animation in your view
    [self.meter.layer addAnimation:fullRotation forKey:@"330"];
    [self performSelector:@selector(stopRotate:) withObject:self.meter afterDelay:2.0];
}];

Answer 1

您需要使用以下宏將弧度轉換為度：

#define RADIANS_TO_DEGREES(radians) ((radians) * (180.0 / M_PI))

並將值傳遞給函數：

-(UIImage*)rotateImage:(UIImage*)img forAngle:(CGFloat)degree   {

UIView *rotatedViewBox = [[UIView alloc]initWithFrame:CGRectMake(0, 0, img.size.width, img.size.height)];
CGAffineTransform t = CGAffineTransformMakeRotation(degree);
rotatedViewBox.transform = t;
CGSize rotatedSize = rotatedViewBox.frame.size;

UIGraphicsBeginImageContext(rotatedSize);

CGContextRef context = UIGraphicsGetCurrentContext();
CGContextTranslateCTM(context, rotatedSize.width, rotatedSize.height);
CGContextRotateCTM(context, radian);
CGContextScaleCTM(context, 1.0, -1.0);

CGContextDrawImage(context, CGRectMake(-img.size.width, -img.size.height, img.size.width, img.size.height), img.CGImage);
UIImage *returnImg = UIGraphicsGetImageFromCurrentImageContext();

UIGraphicsEndImageContext();
return returnImg;
}

Answer 2

嘗試此操作，只需更改基本屬性即可滿足您的要求：

    CATransform3D rotationTransform = CATransform3DMakeRotation(((4) * (180.0 / M_PI)), 0, 0, 1.0);

    CABasicAnimation* rotationAnimation;
    rotationAnimation = [CABasicAnimation animationWithKeyPath:@"transform"];
    rotationAnimation.toValue = [NSValue valueWithCATransform3D:rotationTransform];
    rotationAnimation.duration = 0.6f;
    rotationAnimation.cumulative = YES;
    rotationAnimation.repeatCount = 1;

    //Add this two lines
    rotationAnimation.fillMode = kCAFillModeForwards;
    rotationAnimation.removedOnCompletion = NO;

    [self.meter.layer addAnimation:rotationAnimation forKey:@"rotationAnimation"];

讓我知道這對您有用。

Answer 3

//在標題前綴中添加

 #define MAXFLOAT    0x1.fffffep+127f

//添加旋轉

 [UIView animateWithDuration:1.5 animations:^{
      CABasicAnimation *fullRotation;
    fullRotation = [CABasicAnimation animationWithKeyPath:@"transform.rotation"];
    fullRotation.fromValue = [NSNumber numberWithFloat:0];
    fullRotation.toValue = [NSNumber numberWithFloat:(2*M_PI))];
    fullRotation.duration =1.0f;
    fullRotation.repeatCount = MAXFLOAT;
    // add animation in your view
    [yourView.layer addAnimation:fullRotation forKey:@"360"];
    [self performSelector:@selector(stopRotate:) withObject:yourView afterDelay:1.0];
}];

並添加此代碼以停止旋轉

-(void)stopRotate :(UIView *)yourView
{
  [yourView.layer removeAnimationForKey:@"360"];
}