c# - Unity3D通过Xcode访问变量集

Question

我正在创建一个使用设备摄像头的应用程序。我需要实现一个功能来检查用户是否允许应用程序访问设备相机，如果没有，使用相机的场景只会显示黑屏。

由于Unity在webplayer平台只支持Application.HasUserAuthorization，所以需要在build后通过XCode给项目添加授权检查。

首先，我在 UnityAppController.mm 文件中的 didFinishLaunchingWithOptions 中添加了以下代码:

// Determine camera access on iOS >= 7
if ([AVCaptureDevice respondsToSelector:@selector(requestAccessForMediaType:completionHandler:)]) {
    // Completion handler will be dispatched on a separate thread
    [AVCaptureDevice requestAccessForMediaType:AVMediaTypeVideo completionHandler:^(BOOL granted) {
        if (YES == granted) {
            // User granted access to the camera, continue with app launch
            CameraIsAvailable = YES;
            CameraCheckDone = YES;
        }
        else {
            CameraIsAvailable = NO;
            CameraCheckDone = YES;

        }

    }];
}

else {
    // iOS < 7 (camera access always OK)
    CameraCheckDone = YES;
    // Continue with app launch...
}

和下面的代码到applicationDidBecomeActive

while (!CameraCheckDone) { }
    if(!CameraIsAvailable){
        UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"Authorize Camera"
                                                            message:@"Instructions go here"
                                                           delegate:self
                                                  cancelButtonTitle:@"OK"
                                                  otherButtonTitles:nil];
        [alertView show];
        [alertView release];

    }

结果是每次应用运行时，都会出现一个弹出窗口，指示用户激活相机，这是一个进步，但他们仍然可以访问显示黑屏而不是相机 View 的场景。

有什么方法可以让我从 Unity 中访问 CameraIsAvilable 变量？

如有任何建议，我们将不胜感激! TIA!

Answer 1

我使用UnitySendMessage 函数解决了这个问题。

首先我更新了UnityAppController.mm中的didFinishLaunchingWithOptions，这里是修改后的代码:

// Determine camera access on iOS >= 7
if ([AVCaptureDevice respondsToSelector:@selector(requestAccessForMediaType:completionHandler:)]) {
    // Completion handler will be dispatched on a separate thread
    [AVCaptureDevice requestAccessForMediaType:AVMediaTypeVideo completionHandler:^(BOOL granted) {
        if (YES == granted) {
            // User granted access to the camera, continue with app launch
            CameraIsAvailable = YES;
            CameraCheckDone = YES;

// ADDED THE FOLLOWING LINE THAT SENDS VALUE "YES" WHEN CAMERA ALLOWED
            UnitySendMessage("iOSManager", "cameraCheck", "YES");
        }
        else {
            CameraIsAvailable = NO;
            CameraCheckDone = YES;
// ADDED THE FOLLOWING LINE THAT SENDS VALUE "NO" WHEN CAMERA IS NOT ALLOWED
            UnitySendMessage("iOSManager", "cameraCheck", "NO");

        }

    }];
}

else {
    // iOS < 7 (camera access always OK) 
    CameraCheckDone = YES;
    // Continue with app launch...
}

然后在 Unity3D 中，我在游戏的第一个场景中添加了一个名为“iOSManager”的游戏对象(注意:游戏对象名称必须与 UnitySendMessage 函数的第一个参数匹配)。

我使用 cameraCheck() 函数创建了以下脚本(函数名称与 UnitySendMessage 函数的第二个参数匹配):

#if UNITY_IOS
void cameraCheck(string value)
{
    // DO SOMETHING WITH VALUE
}
#endif

其中字符串“value”是UnitySendMessage发送的值

现在我可以在 Unity3D 中使用这个值