为什么禁用允许编辑时，iPhone 上的相机拍摄的全屏照片不显示在 UIImageview 中？

Question

在我的应用程序中，我从 iPhone 相机拍摄照片并将这些照片放入带有图像的 ScrollView。

问题是它只有在我设置时才适用于我的情况

picker.allowsEditing = YES

但在这种情况下，照片只会以正方形形式保存（感谢allowEditing 是相机功能中的一个选择正方形）。

如果我取出这行代码（我想要的是完整的照片，而不仅仅是选定的正方形），那么占位符图像将被任何内容替换。

这里是需要的方法：

- (IBAction)takePhoto:(UIButton *)sender{
UIImagePickerController *picker = [[UIImagePickerController alloc] init];
picker.delegate = self;
//picker.allowsEditing = YES;
picker.sourceType = UIImagePickerControllerSourceTypeCamera;
[self presentViewController:picker animated:YES completion:NULL];}

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info{
UIImageView *image = (UIImageView *)[self.view viewWithTag:[self getCurrentPageNumber]];
UIImage *chosenImage = info[UIImagePickerControllerEditedImage];
image.image = chosenImage;
[picker dismissViewControllerAnimated:YES completion:NULL];}

-(void)addImageToImageScrollView:(CGFloat)x y:(CGFloat)y width:(CGFloat)width height:(CGFloat)height {
UIView *view = [[UIView alloc] initWithFrame:CGRectMake(x, y, width, height)]; 
UIImageView *imgView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, view.frame.size.width, view.frame.size.height)];
imgView.image = [UIImage imageNamed:@"placeholder.png"];
imgView.contentMode = UIViewContentModeScaleAspectFit;
[imgView setTag:([self getCurrentPageNumber]+1)];
UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
[button addTarget:self action:@selector(imageScrollViewButtonPressed:) forControlEvents:UIControlEventTouchDown];
button.frame = CGRectMake(0, 0, view.frame.size.width, view.frame.size.height);
[button setTag:([self getCurrentPageNumber]+1)];    
[view addSubview:imgView];
[view addSubview:button];
[imageScrollView addSubview:view];}

Answer 1

它与 UIImagePickerControllerDelegate 协议有关

当您将allowsEditing 设置为yes 时，您将在委托方法触发时开始接收一个充满有用信息的NSDictionary：

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info{

当您拨打 UIImage *chosenImage = info[UIImagePickerControllerEditedImages]; 时，您正在使用其中的一些信息

通过将allowsEditing 设置为NO，委托方法将为info 参数传递nil。

您可以通过在方法中设置断点来确认这一点，进入并观察 info 将为 nil，这意味着您将 *chosenImage 设置为 nil。