iphone - 如何在 iPhone 中以编程方式将图像旋转 90 度？

Question

可能重复：
如何将 UIImage 旋转 90 度？

如何在 iPhone 中以编程方式将图像旋转 90 度？

Answer 1

//create rect
UIImageView *myImageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"my_image.png"]];

//set point of rotation
myImageView.center = CGPointMake(100.0, 100.0);

//rotate rect
myImageView.transform = CGAffineTransformMakeRotation(M_PI_2); //rotation in radians

Answer 2

看到这个：

在 Quartz 中旋转图像？图像是颠倒的！（苹果手机）

 myImage.center = CGPointMake(0, 0);
 myImage.transform = CGAffineTransformMakeRotation([degreesToRadians:imageRotationFix]);

Answer 3

此代码将旋转按钮..

UIButton *btn=[UIButton buttonWithType:UIButtonTypeRoundedRect];
[btn setFrame:CGRectMake(100, 100, 200, 44)];
btn.transform=CGAffineTransformMakeRotation(M_PI / -4);
[btn setTitle:@"RakeshBhatt" forState:UIControlStateNormal];
[self.view addSubview:btn];

同样的方式你可以旋转imageview。