There is setAutoExposureLock() method in the old camera api.
And also it is possible to lock the exposure like this in camera2:
builder.set(CaptureRequest.CONTROL_AE_LOCK, true);
How to do this in CameraX? Right now I'm using ImageCapture.Builder to take a picture. Quick internet search didn't give me the answer.
You are looking for the Camera2InterOp API. https://developer.android.com/reference/androidx/camera/camera2/interop/Camera2Interop
ImageCapture.Builder builder = new ImageCapture.Builder();
Camera2Interop.Extender<ImageCapture> extender = new Camera2Interop.Extender<>(builder);
extender.setCaptureRequestOption(CaptureRequest.CONTROL_AE_LOCK, true);