iPhone UIImagePickerController didFinishPickingImage:UIImage在视图控制器之间传输？

在我的应用程序中，我有一个UIImagePickerController。选择图像后，“我的视图控制器”需要获取图像并将其传递给另一个视图控制器，该视图控制器被推送到self.navigationController上。但我总是会遇到错误或零争论，诸如此类的事情。如果您能告诉我此代码有什么问题，我将不胜感激：

FirstViewController.m：

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingImage:(UIImage *)img editingInfo:(NSDictionary *)editInfo {
 self.currentpicture = [img copy];
 [self dismissModalViewControllerAnimated:YES];
 [self goNext];
}
-(void)goNext{
 SecondViewController *vc = [[SecondViewController alloc] initWithNibName:@"Second" bundle:nil];
 [vc giveMePicture:currentpicture];
 [self.navigationController pushViewController:vc animated:YES];
}

-(void)giveMePicture:(UIImage *)data {
 self.currentpicture=[data copy];
}

SecondViewController.m：

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingImage:(UIImage *)img editingInfo:(NSDictionary *)editInfo {
 self.currentpicture = [img copy];
 [self dismissModalViewControllerAnimated:YES];
 [self goNext];
}
-(void)goNext{
 SecondViewController *vc = [[SecondViewController alloc] initWithNibName:@"Second" bundle:nil];
 [vc giveMePicture:currentpicture];
 [self.navigationController pushViewController:vc animated:YES];
}

-(void)giveMePicture:(UIImage *)data {
 self.currentpicture=[data copy];
}

它们都将currentpicture定义为UIImage*currentpicture

---

我现在应该将currentpicture作为一些数据，但它每次都崩溃！我尝试过很多不同的事情，但我无法理解这一点

在不同视图控制器类之间共享数据的一种方法是通过应用程序委托

例如，您可以在应用程序委托中定义

UIImage*currentPicture

，然后在两个视图控制器类中进行访问，如下所示：

MyAppDelegate *appDelegate = (MyAppDelegate*)[[UIApplication sharedApplication]delegate];
UIImage *i = [appDelegate.currentPicture];

---

如果我错了，请纠正我，但UIImage不符合NSCopying，因此您无法成功复制它

您可能想做的是保留图像。如果self.currentpicture是“retain”属性，它将自动释放以前的对象并保留新对象，因此只需执行以下操作：

self.currentpicture = img;

否则，请自己动手：

[self.currentpicture release];
self.currentpicture = [img retain];

在这两种情况下，当您不再需要图像时，仍然必须调用[self.currentpicture release]。通常，您会在“self”对象的dealoc方法中执行此操作