iOS --- 使用runtime解决3D Touch导致UIImagePicker崩溃的问题

UIImagePickerController *imagePickerController = [[UIImagePickerController alloc] init];
// 设置sourceType为系统相册, 如果使用Camera请对应修改该属性.
imagePickerController.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
imagePickerController.allowsEditing = YES;
imagePickerController.delegate = self;
[self presentViewController:imagePickerController animated:YES completion:nil];

(lldb) po [picker viewControllers]
<__NSArrayI 0x146b31140>(
    <PUUIAlbumListViewController: 0x14609a200>,
    <PUUIPhotosAlbumViewController: 0x1458e5a00>,
    <PUUIImageViewController: 0x1468f1ad0>
)

__TVOS_PROHIBITED @protocol UIImagePickerControllerDelegate<NSObject>
@optional
// The picker does not dismiss itself; the client dismisses it in these callbacks.
// The delegate will receive one or the other, but not both, depending whether the user
// confirms or cancels.
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingImage:(UIImage *)image editingInfo:(nullable NSDictionary<NSString *,id> *)editingInfo NS_DEPRECATED_IOS(2_0, 3_0);
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary<NSString *,id> *)info;
- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker;

// info dictionary keys
UIKIT_EXTERN NSString *const UIImagePickerControllerMediaType __TVOS_PROHIBITED;      // an NSString (UTI, i.e. kUTTypeImage)
UIKIT_EXTERN NSString *const UIImagePickerControllerOriginalImage __TVOS_PROHIBITED;  // a UIImage
UIKIT_EXTERN NSString *const UIImagePickerControllerEditedImage __TVOS_PROHIBITED;    // a UIImage
UIKIT_EXTERN NSString *const UIImagePickerControllerCropRect __TVOS_PROHIBITED;       // an NSValue (CGRect)
UIKIT_EXTERN NSString *const UIImagePickerControllerMediaURL __TVOS_PROHIBITED;       // an NSURL
UIKIT_EXTERN NSString *const UIImagePickerControllerReferenceURL        NS_AVAILABLE_IOS(4_1) __TVOS_PROHIBITED;  // an NSURL that references an asset in the AssetsLibrary framework
UIKIT_EXTERN NSString *const UIImagePickerControllerMediaMetadata       NS_AVAILABLE_IOS(4_1) __TVOS_PROHIBITED;  // an NSDictionary containing metadata from a captured photo
UIKIT_EXTERN NSString *const UIImagePickerControllerLivePhoto NS_AVAILABLE_IOS(9_1) __TVOS_PROHIBITED;  // a PHLivePhoto
}

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary<NSString *,id> *)info {
    UIImage *originalImage = info[UIImagePickerControllerOriginalImage];
    UIImage *editedImage = info[UIImagePickerControllerEditedImage];
    UIImage *savedImage = editedImage ?: originalImage;

    if (picker.sourceType == UIImagePickerControllerSourceTypeCamera) {
        UIImageWriteToSavedPhotosAlbum(savedImage, nil, nil, nil);
    }

    __weak ViewController *weakSelf = self;
    [picker dismissViewControllerAnimated:YES completion:^{
        weakSelf.imageView.image = savedImage;
    }];
}

- (void)replaceSelectorForClass:(Class)cls
                  SelectorOriginal:(SEL)original
                   SelectorReplace:(SEL)replacement
                    withBlock:(id)block {

    IMP implementation = imp_implementationWithBlock(block);
    Method originalMethod = class_getInstanceMethod(cls, original);
    class_addMethod(cls, replacement, implementation, method_getTypeEncoding(originalMethod));
    Method replacementMethod = class_getInstanceMethod(cls, replacement);
    if (class_addMethod(cls, original, method_getImplementation(replacementMethod), method_getTypeEncoding(replacementMethod))) {
        class_replaceMethod(cls, replacement, method_getImplementation(originalMethod), method_getTypeEncoding(originalMethod));
    } else {
        method_exchangeImplementations(originalMethod, replacementMethod);
    }

}

- (void)preventImagePickerCrashOn3DTouch {
    // Load PhotosUI and bail if 3D Touch is unavailable.
    // (UIViewControllerPreviewing may be redundant,
    // as PUPhotosGridViewController only seems to exist on iOS 9,
    // but I'm being cautious.)
    NSString *photosUIPath = @"/System/Library/Frameworks/PhotosUI.framework";
    NSBundle *photosUI = [NSBundle bundleWithPath:photosUIPath];
    Class photosClass = [photosUI classNamed:@"PUPhotosGridViewController"];
    if (!(photosClass && objc_getProtocol("UIViewControllerPreviewing"))) {
        return;
    }

#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wundeclared-selector"

    SEL selector = @selector(ab_previewingContext:viewControllerForLocation:);
    [self replaceSelectorForClass:photosClass
                 SelectorOriginal:@selector(previewingContext:viewControllerForLocation:)
                  SelectorReplace:selector
                        withBlock:^UIViewController *(id self, id<UIViewControllerPreviewing> previewingContext, CGPoint location) {

        // Default implementation throws on iOS 9.0 and 9.1.
        @try {
            MTLog(@"Replace method at runtime to prevent UIImagePicker crash on 3D Touch.");
            return ((UIViewController *(*)(id, SEL, id, CGPoint))objc_msgSend)(self, selector, previewingContext, location);
        } @catch (NSException *e) {
            return nil;
        }
    }];

#pragma clang diagnostic pop
}