Xamarin Camera2basic cant set flash parameter on runtime - xamarin

Question

I'm using camera2basic, when I change flash parameter on runtime it not working and load first parameter when app loading.
example : when I set auto-flash in hardcode it worked when I change it to Off in my app it not work and flash parameter is auto-flash yet.
I want to set flash parameter in application not hardcode. How can i do it?
**//Camera2BasicFragment.cs**
public void CaptureStillPicture()
{
try
{
var activity = Activity;
if (null == activity || null == mCameraDevice)
{
return;
}
// This is the CaptureRequest.Builder that we use to take a picture.
if (stillCaptureBuilder == null)
stillCaptureBuilder = mCameraDevice.CreateCaptureRequest(CameraTemplate.StillCapture);
stillCaptureBuilder.AddTarget(mImageReader.Surface);
SetFlash(stillCaptureBuilder);
// Orientation
int rotation = (int)activity.WindowManager.DefaultDisplay.Rotation;
stillCaptureBuilder.Set(CaptureRequest.JpegOrientation, GetOrientation(rotation));
mCaptureSession.StopRepeating();
mCaptureSession.Capture(stillCaptureBuilder.Build(), new CameraCaptureStillPictureSessionCallback(this), null);
}
catch (CameraAccessException e)
{
e.PrintStackTrace();
}
}
ControlAEMode AeFlashMode = ControlAEMode.Off;
public void SetFlash(CaptureRequest.Builder requestBuilder)
{
if (mFlashSupported)
{
requestBuilder.Set(CaptureRequest.ControlAeMode, (int)AeFlashMode);
}
}
-------------------------------
**//CameraCaptureSessionCallback.cs**
public override void OnConfigured(CameraCaptureSession session)
{
// The camera is already closed
if (null == owner.mCameraDevice)
{
return;
}
// When the session is ready, we start displaying the preview.
owner.mCaptureSession = session;
try
{
// Auto focus should be continuous for camera preview.
owner.SetFocus(owner.mPreviewRequestBuilder);
// Flash is automatically enabled when necessary.
owner.SetFlash(owner.mPreviewRequestBuilder);
// Finally, we start displaying the camera preview.
owner.mPreviewRequest = owner.mPreviewRequestBuilder.Build();
owner.mCaptureSession.SetRepeatingRequest(owner.mPreviewRequest,
owner.mCaptureCallback, owner.mBackgroundHandler);
}
catch (CameraAccessException e)
{
e.PrintStackTrace();
}
}

Answer 1

You can add following code to your CameraCaptureSessionCallback.cs
public void ISFlashOpenOrClose(bool isTorchOn)
{
owner.mCaptureSession = this.session;
if (isTorchOn)
{
owner.mPreviewRequestBuilder.Set(CaptureRequest.FlashMode, (int)ControlAEMode.On);
// owner.mPreviewRequestBuilder.Set(CaptureRequest.FlashMode, (int)FlashMode.Off);
// mPreviewSession.SetRepeatingRequest(mPreviewBuilder.build(), null, null);
owner.mPreviewRequest = owner.mPreviewRequestBuilder.Build();
owner.mCaptureSession.SetRepeatingRequest(owner.mPreviewRequest,
owner.mCaptureCallback, owner.mBackgroundHandler);
// isTorchOn = false;
}
else
{
owner.mPreviewRequestBuilder.Set(CaptureRequest.ControlAeMode, (int)ControlAEMode.Off);
owner.mPreviewRequest = owner.mPreviewRequestBuilder.Build();
owner.mCaptureSession.SetRepeatingRequest(owner.mPreviewRequest,
owner.mCaptureCallback, owner.mBackgroundHandler);
}
}
Here is all of code about CameraCaptureSessionCallback.cs
public class CameraCaptureSessionCallback : CameraCaptureSession.StateCallback
{
private readonly Camera2BasicFragment owner;
CameraCaptureSession session;
public CameraCaptureSessionCallback(Camera2BasicFragment owner)
{
if (owner == null)
throw new System.ArgumentNullException("owner");
this.owner = owner;
}
public override void OnConfigureFailed(CameraCaptureSession session)
{
owner.ShowToast("Failed");
}
private bool isTorchOn;
public override void OnConfigured(CameraCaptureSession session)
{
// The camera is already closed
if (null == owner.mCameraDevice)
{
return;
}
this.session = session;
// When the session is ready, we start displaying the preview.
owner.mCaptureSession = session;
try
{
// Auto focus should be continuous for camera preview.
owner.mPreviewRequestBuilder.Set(CaptureRequest.ControlAfMode, (int)ControlAFMode.ContinuousPicture);
// Flash is automatically enabled when necessary.
owner.SetAutoFlash(owner.mPreviewRequestBuilder);
// Flash is automatically enabled when necessary.
// owner.SetFlash(owner.mPreviewRequestBuilder);
// Finally, we start displaying the camera preview.
owner.mPreviewRequest = owner.mPreviewRequestBuilder.Build();
owner.mCaptureSession.SetRepeatingRequest(owner.mPreviewRequest,
owner.mCaptureCallback, owner.mBackgroundHandler);
}
catch (CameraAccessException e)
{
e.PrintStackTrace();
}
}
public void ISFlashOpenOrClose(bool isTorchOn)
{
owner.mCaptureSession = this.session;
if (isTorchOn)
{
owner.mPreviewRequestBuilder.Set(CaptureRequest.FlashMode, (int)ControlAEMode.On);
// owner.mPreviewRequestBuilder.Set(CaptureRequest.FlashMode, (int)FlashMode.Off);
// mPreviewSession.SetRepeatingRequest(mPreviewBuilder.build(), null, null);
owner.mPreviewRequest = owner.mPreviewRequestBuilder.Build();
owner.mCaptureSession.SetRepeatingRequest(owner.mPreviewRequest,
owner.mCaptureCallback, owner.mBackgroundHandler);
// isTorchOn = false;
}
else
{
owner.mPreviewRequestBuilder.Set(CaptureRequest.ControlAeMode, (int)ControlAEMode.Off);
owner.mPreviewRequest = owner.mPreviewRequestBuilder.Build();
owner.mCaptureSession.SetRepeatingRequest(owner.mPreviewRequest,
owner.mCaptureCallback, owner.mBackgroundHandler);
}
}
}
}
You can change it by ISFlashOpenOrClose method at runtime.