ios如何在Xcode中创建简单的相机覆盖？

Question

正如标题所说，我需要在使用UIImagePickerController 拍照时创建一个非常简单的相机叠加层。我想在相机上添加非常简单的.png 文件（如一个空框），但我不知道该怎么做。

我查看了此网页中的大部分教程，但其中大部分内容并不了解。对我来说这似乎很难，将一个简单的.png 文件添加到相机叠加层应该比这更容易。

(IBAction) getPhoto:(id) sender {
    UIImagePickerController * picker = [[UIImagePickerController alloc] init];
    picker.delegate = self;

    if((UIButton *) sender == choosePhotoBtn) {
        picker.sourceType = UIImagePickerControllerSourceTypeCamera;
    } else {

    }

    label1.text =@"PHOTO ACTION";

    [self presentModalViewController:picker animated:YES];
}

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {
    [picker dismissModalViewControllerAnimated:YES];
    imageView.image = [info objectForKey:@"UIImagePickerControllerOriginalImage"];
}

我应该在哪里实现我的叠加代码？我应该使用哪些类以及如何使用？

Answer 1

UIImagePickerController 的属性称为cameraOverlayView。这是一个UIView*，所以你需要创建一个并将你的PNG放到它的背景上，然后将它分配给你的picker的这个属性。

好的，这是代码（我没有测试过）

(IBAction) getPhoto:(id) sender 
{
    UIImagePickerController * picker = [[UIImagePickerController alloc] init];
    picker.delegate = self;

    // creating overlayView
    UIView* overlayView = [[UIView alloc] initWithFrame:picker.view.frame];
    // letting png transparency be
    overlayView.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:@"yourimagename.png"]];
    [overlayView.layer setOpaque:NO];
    overlayView.opaque = NO;

    picker.showsCameraControls = NO;
    picker.cameraOverlayView = overlayView;

    if((UIButton *) sender == choosePhotoBtn) 
    {
         if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera])
         {
             [picker setSourceType:UIImagePickerControllerSourceTypeCamera];
         } else {
             //do something if the device has no camera or if the camera is disabled in settings (it cannot be assumed that the camera is available/not broken)
         }
    } else {

    }

    label1.text =@"PHOTO ACTION";

    [self presentModalViewController:picker animated:YES];
}

当然，您可以使用一些自定义的UIView* 子类而不是创建标准的UIView* overlayView，但其他一切都将保持不变。