UIImageView在iPhone Sdk中旋转和缩放

Question

我在我的项目中使用UIImageview实现缩放和旋转， 我在旋转图像时遇到放大和缩小问题，

以下是我的代码：

<。>文件中的

@interface ViewController : UIViewController{
 float degrees;
 float height;
 float width;

float moveLeft;
float moveRight;
}

@property(nonatomic,retain)UIImageView *imageView;

-(IBAction)rotationLeft:(id)sender;
-(IBAction)rotationRight:(id)sender;
-(IBAction)zoomIn:(id)sender;
-(IBAction)zoomOut:(id)sender;

-(IBAction)moveLeft:(id)sender;
-(IBAction)moveRight:(id)sender; 

<。>文件中的

- (void)viewDidLoad
{
[super viewDidLoad];



height=50;
width=50;
degrees=20;
moveLeft=20;
moveRight=20;
imageView=[[UIImageView alloc]initWithImage:[UIImage imageNamed:@"1.png"]];
imageView.frame=CGRectMake(100, 100,width, height);
[self.view addSubview:imageView];



// Do any additional setup after loading the view, typically from a nib.
}
-(IBAction)rotationLeft:(id)sender{
//the value in degrees
imageView.transform = CGAffineTransformMakeRotation(degrees*M_PI/180);
degrees=degrees+25;
}

-(IBAction)rotationRight:(id)sender{
//the value in degrees
degrees=degrees-25;
imageView.transform = CGAffineTransformMakeRotation(degrees*M_PI/180);

}
-(IBAction)zoomIn:(id)sender{
height=height-15;
width=width-15;
imageView.frame=CGRectMake(100, 100,width, height);
}
-(IBAction)zoomOut:(id)sender{
height=height+15;
width=width+15;
imageView.frame=CGRectMake(100, 100,width, height);
}

请查看随附的图片供您参考。

Answer 1

您应该使用CGAffineTransformMakeScale进行缩放，而不是强制使用框架。

在某处定义全局foal x = 1;然后：

-(IBAction)zoomIn:(id)sender{
   x += 0.3;
   imageView.transform = CGAffineTransformMakeScale(x, x);
}

-(IBAction)zoomOut:(id)sender{
   x -= 0.3;
   imageView.transform = CGAffineTransformMakeScale(x, x);
}

Answer 2

我建议使用与您拥有的旋转代码非常相似的方法缩放图像：

CGAffineTransformMakeScale(CGFloat sx, CGFloat sy);

只需向上发送1.0以上即可向上扩展，小于1.0可向下扩展;

Answer 3

下面的代码对我来说很完美！

-(IBAction)rotationLeft:(id)sender{
//the value in degrees
    degrees=degrees+25;
    CGAffineTransform t;
    t=CGAffineTransformMakeScale(x, x);
    // imageView.transform = CGAffineTransformMakeRotation(degrees*M_PI/180,x,x);
    imageView.transform=CGAffineTransformRotate(t, degrees*M_PI/180);
}

-(IBAction)rotationRight:(id)sender{
    degrees=degrees-25;
    CGAffineTransform t;
    t=CGAffineTransformMakeScale(x, x);
    imageView.transform=CGAffineTransformRotate(t, degrees*M_PI/180);

 }
 -(IBAction)zoomIn:(id)sender{
    x += 0.3;
    CGAffineTransform t;
    t=CGAffineTransformMakeRotation(degrees*M_PI/180);
    imageView.transform=CGAffineTransformScale(t, x, x);
 }

 -(IBAction)zoomOut:(id)sender{
     x -= 0.3;
    CGAffineTransform t;
    t=CGAffineTransformMakeRotation(degrees*M_PI/180);
    imageView.transform=CGAffineTransformScale(t, x, x);
 }