Rotate a UIImage or UIView to a particular angle, NOT an amount of angle
Objective-C for iOS.
How do I rotate an image or view TO a particular angle. I have tried the two methods below, but both rotate the AMOUNT of angle, not TO the angle. Basically I would like to call a method to rotate to 90' and then say call again of 180', and the image/view to finish at 180', NOT an addition of them both (270') which is what happens if I use either of the methods below.
#define degreesToRadians(degrees) (M_PI * degrees / 180.0)
myImage.transform = CG开发者_如何学运维AffineTransformMakeRotation(degreesToRadians(90));
myImage.transform = CGAffineTransformRotate(myImage.transform, degreesToRadians(90));
Many thanks!
Reset by
.transform = CGAffineTransformIdentity
before the other transforms...
ohho's answer can be useful if you haven't to do animation. I found useful this trick:
[UIView animateWithDuration:0.2 animations:^{
self.compassImgView.transform = CGAffineTransformRotate(CGAffineTransformIdentity, radians);
}];
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