iOS14 儲存圖檔到相冊

iOS14以後，儲存圖檔的正确姿勢

如果你在PHAuthorizationStatusLimited 的權限下，儲存圖檔遇到了問題，請參考下面的代碼

// 儲存圖檔到相冊
    if (@available(iOS 14,*)) {
        WeakSelf
        [[PHPhotoLibrary sharedPhotoLibrary]performChanges:^{
            [PHAssetChangeRequest creationRequestForAssetFromImage:image];
        } completionHandler:^(BOOL success, NSError * _Nullable error) {
            dispatch_sync(dispatch_get_main_queue(), ^{
                StrongSelf
                 if (error != nil){
                     [MBProgressHUD showMessage:@"二維碼儲存失敗" inView:KKeyWindow];
                 }else{
                     [MBProgressHUD showMessage:@"二維碼儲存成功" inView:KKeyWindow];
                 }
                [strongSelf dismiss];
            });
        }];
    }else {
        UIImageWriteToSavedPhotosAlbum(image, self, @selector(image:didFinishSavingWithError:contextInfo:), nil);
    }

- (void)image:(UIImage *)image didFinishSavingWithError:(NSError *)error contextInfo:(void *)contextInfo {
    if (error) {
        // 儲存失敗
        [MBProgressHUD showMessage:@"二維碼儲存失敗" inView:self.invisibleAutoSave == YES ? KKeyWindow : self];
    } else {
        // 儲存成功
        [MBProgressHUD showMessage:@"二維碼儲存成功" inView:self.invisibleAutoSave == YES ? KKeyWindow : self];
    }
    dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0.5 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
        [self dismiss];
    });
}