UIImageView能否仅旋转图像?我正在寻找相关信息,但只找到了有关旋转UIImageVeiw的信息。
UIImageView能否仅旋转图像?我正在寻找相关信息,但只找到了有关旋转UIImageVeiw的信息。
你可以使用以下代码旋转图片。注意,这里使用的是CGImageRef,您可以通过UIImage获取它
CGImageRef imageRef = [self CGImageRotatedByAngle:[image CGImage] angle:30];
获取旋转后的图像后,您可以设置ImageView的图像为新旋转的图像,方法如下:
UIImage* img = [UIImage imageWithCGImage: imageRef];
myImageView.image = img;
这里有一个方法可以旋转imageRef图片:
- (CGImageRef)CGImageRotatedByAngle:(CGImageRef)imgRef angle:(CGFloat)angle
{
CGFloat angleInRadians = angle * (M_PI / 180);
CGFloat width = CGImageGetWidth(imgRef);
CGFloat height = CGImageGetHeight(imgRef);
CGRect imgRect = CGRectMake(0, 0, width, height);
CGAffineTransform transform = CGAffineTransformMakeRotation(angleInRadians);
CGRect rotatedRect = CGRectApplyAffineTransform(imgRect, transform);
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
CGContextRef bmContext = CGBitmapContextCreate(NULL,
rotatedRect.size.width,
rotatedRect.size.height,
8,
0,
colorSpace,
kCGImageAlphaPremultipliedFirst);
CGContextSetAllowsAntialiasing(bmContext, YES);
CGContextSetShouldAntialias(bmContext, YES);
CGContextSetInterpolationQuality(bmContext, kCGInterpolationHigh);
CGColorSpaceRelease(colorSpace);
CGContextTranslateCTM(bmContext,
+(rotatedRect.size.width/2),
+(rotatedRect.size.height/2));
CGContextRotateCTM(bmContext, angleInRadians);
CGContextTranslateCTM(bmContext,
-(rotatedRect.size.width/2),
-(rotatedRect.size.height/2));
CGContextDrawImage(bmContext, CGRectMake(0, 0,
rotatedRect.size.width,
rotatedRect.size.height),
imgRef);
CGImageRef rotatedImage = CGBitmapContextCreateImage(bmContext);
CFRelease(bmContext);
[(id)rotatedImage autorelease];
return rotatedImage;
}
看一下如何旋转ImageView的层。您需要导入QuartzCore库才能使其可访问。
myImageView.layer.transform = CGAffineTransformMakeRotation (1.5);
setAffineTransform
。 - fabian789[UIView beginAnimations:nil context:nil];
[UIView setAnimationBeginsFromCurrentState:YES];
[UIView setAnimationCurve:UIViewAnimationCurveEaseIn];
[UIView setAnimationRepeatCount:10];
myImgView.transform = CGAffineTransformMakeRotation(M_PI);
[UIView commitAnimations];
祝你好运!
let img = UIImage(CGImage: self.imageView.image!.CGImage, scale: 1.0, orientation: UIImageOrientation.Right)
self.imageView.image = img
self.imageView.setNeedsLayout()
imageView.image = imageView.image?.imageFlippedForRightToLeftLayoutDirection()