Rotate imageView as per touch - ios

Question

I am rotating imageView which is minuit hand of a clock, with
-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *touch = [touches anyObject];
if ([touch view] == _imgViewMinuit)
{
NSLog(#"Touched");
_imgMinuitHand.transform = CGAffineTransformRotate(_imgMinuitHand.transform,DEGREES_RADIANS(6));
}
}
Now i want to rotate it as per my finger, clockwise/anticlockwise, with speed of my touch.
How I can achieve this ?

Answer 1

check this code
-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *touch=[[event allTouches]anyObject];
[self transformSpinnerwithTouches:touch];
}
-(void)transformSpinnerwithTouches:(UITouch *)touchLocation
{
CGPoint touchLocationpoint = [touchLocation locationInView:self.view];
CGPoint PrevioustouchLocationpoint = [touchLocation previousLocationInView:self.view];
//origin is the respective piont from that i gonna measure the angle of the current position with respective to previous position ....
CGPoint origin;
origin.x = arrow.center.x;
origin.y = arrow.center.y;
CGPoint previousDifference = [self vectorFromPoint:origin toPoint:PrevioustouchLocationpoint];
CGAffineTransform newTransform = CGAffineTransformScale(arrow.transform, 1, 1);
CGFloat previousRotation = atan2(previousDifference.y, previousDifference.x);
CGPoint currentDifference = [self vectorFromPoint:origin toPoint:touchLocationpoint];
CGFloat currentRotation = atan2(currentDifference.y, currentDifference.x);
CGFloat newAngle = currentRotation- previousRotation;
temp1 = temp1 + newAngle;
//NSLog(#"temp1 is %f",temp1);
//NSLog(#"Angle:%F\n",(temp1*180)/M_PI);
newTransform = CGAffineTransformRotate(newTransform, newAngle);
[self animateView:arrow toPosition:newTransform];
}
-(void)animateView:(UIView *)theView toPosition:(CGAffineTransform) newTransform
{
arrow.transform = newTransform;
}
-(CGPoint)vectorFromPoint:(CGPoint)firstPoint toPoint:(CGPoint)secondPoint
{
CGFloat x = secondPoint.x - firstPoint.x;
CGFloat y = secondPoint.y - firstPoint.y;
CGPoint result = CGPointMake(x, y);
//NSLog(#"%f %f",x,y);
return result;
}