Kotlin - 常量的未解决的参考

Question

我想为我的android应用程序使用新相机硬件API（android.hardware.camera2）的示例代码。首先，我通过Android Studio的Kotlin插件的自动转换功能将Java代码转换为Kotlin代码。下面是一块转换代码：

private val mCaptureCallback = object : CameraCaptureSession.CaptureCallback() { 

    private fun process(result: CaptureResult) { 
     when (mState) { 
      STATE_PREVIEW -> { 
      }// We have nothing to do when the camera preview is working normally. 
      STATE_WAITING_LOCK -> { 
       val afState = result.get(CaptureResult.CONTROL_AF_STATE) 
       if (CaptureResult.CONTROL_AF_STATE_FOCUSED_LOCKED == afState || CaptureResult.CONTROL_AF_STATE_NOT_FOCUSED_LOCKED == afState) { 
        // CONTROL_AE_STATE can be null on some devices 
        val aeState = result.get<Int>(CaptureResult.CONTROL_AE_STATE) 
        if (aeState == null || aeState == CaptureResult.CONTROL_AE_STATE_CONVERGED) { 
         mState = STATE_WAITING_NON_PRECAPTURE 
         captureStillPicture() 
        } else { 
         runPrecaptureSequence() 
        } 
       } 
      } 
      STATE_WAITING_PRECAPTURE -> { 
       // CONTROL_AE_STATE can be null on some devices 
       val aeState = result.get<Int>(CaptureResult.CONTROL_AE_STATE) 
       if (aeState == null || aeState == CaptureResult.CONTROL_AE_STATE_PRECAPTURE || aeState == CaptureRequest.CONTROL_AE_STATE_FLASH_REQUIRED) { 
        mState = STATE_WAITING_NON_PRECAPTURE 
       } 
      } 
      STATE_WAITING_NON_PRECAPTURE -> { 
       // CONTROL_AE_STATE can be null on some devices 
       val aeState = result.get<Int>(CaptureResult.CONTROL_AE_STATE) 
       if (aeState == null || aeState != CaptureResult.CONTROL_AE_STATE_PRECAPTURE) { 
        mState = STATE_PICTURE_TAKEN 
        captureStillPicture() 
       } 
      } 
     } 
    } 

我得到的未决引用错误：

CaptureResult.CONTROL_AF_STATE_FOCUSED_LOCKED 
CaptureResult.CONTROL_AF_STATE_NOT_FOCUSED_LOCKED 
CaptureResult.CONTROL_AE_STATE_CONVERGED 
CaptureResult.CONTROL_AE_STATE_PRECAPTURE 
CaptureRequest.CONTROL_AE_STATE_FLASH_REQUIRED 

但是，这些常量在原来的Java代码的认可。有这些错误的解决方案吗？

Answer 1

这些变量在CameraMetadata中声明。在Kotlin中，静态变量和方法不能在子类上调用。