变换objective-c后设置新框架

Question

我在将新框架设置为 uiview 对象时遇到问题。 这是我的代码：

UIImageView *blockImage=[[UIImageView alloc] initWithFrame:CGRectMake(0, [y doubleValue], self.view.frame.size.width, 86)];

[blockImage setImage:[UIImage imageNamed:@"mainscreen_block_sample.jpg"]];
[blockImage setBackgroundColor:[UIColor blackColor]];


//setting anchor point
[blockImage.layer setAnchorPoint:CGPointMake(0.5, 1.0)];

//preparing transform
float distance = 500;
CATransform3D basicTrans = CATransform3DIdentity;
basicTrans.m34 = 1.0 / -distance;

//calculating angle
double OF=oldSize/2.0-difference;
double OC=oldSize/2.0;    
double angle= acosf(OF/OC);
angle=angle/2.0;

//transforming
blockImage.layer.transform = CATransform3DRotate(basicTrans, angle, 1.0f, 0.0f, 0.0f);

double newOriginY=[y doubleValue]-difference;
double newFrameHeight=blockImage.frame.size.height;

[blockImage setFrame:CGRectMake(0, newOriginY, blockImage.frame.size.width, newFrameHeight)];

NSLog(@"    blockImage frame y: %g", blockImage.frame.origin.y);
NSLog(@"    blockImage frame height:   %g", blockImage.frame.size.height);

//adding subview
[blocks addObject:blockImage];
[self.view addSubview:[blocks objectAtIndex:([blocks count]-1)]];

//releasing memory
[blockImage release];

NSLog 输出不可取:(

新矩形的值： 新原产地：78 新帧高度：77.82

但 NSLog 不同： 块图像帧 y：85.0665 blockImage 帧高：70.7535

Answer 1

如果您正在应用变换，则应忽略 frame 属性。您应该适当地设置边界和中心。 UIView 的文档说明了这一点。