问如何使用Android CameraX自动对焦

EN

val factory = DisplayOrientedMeteringPointFactory(activity.display, camera.cameraInfo, previewView.width.toFloat(), previewView.height.toFloat())

private boolean onTouchToFocus(View viewA, MotionEvent event) {
        switch (event.getAction()) {
            case MotionEvent.ACTION_DOWN:
                break;
            case MotionEvent.ACTION_UP:
                    return focus(event);
                break;
            default:
                // Unhandled event.
                return false;
        }
        return true;
    }

private boolean focus(MotionEvent event) {
        final float x = (event != null) ? event.getX() : getView().getX() + getView().getWidth() / 2f;
        final float y = (event != null) ? event.getY() : getView().getY() + getView().getHeight() / 2f;

        TextureViewMeteringPointFactory pointFactory = new TextureViewMeteringPointFactory(textureView);
        float afPointWidth = 1.0f / 6.0f;  // 1/6 total area
        float aePointWidth = afPointWidth * 1.5f;
        MeteringPoint afPoint = pointFactory.createPoint(x, y, afPointWidth, 1.0f);
        MeteringPoint aePoint = pointFactory.createPoint(x, y, aePointWidth, 1.0f);

           try {
            CameraX.getCameraControl(lensFacing).startFocusAndMetering(
                FocusMeteringAction.Builder.from(afPoint, FocusMeteringAction.MeteringMode.AF_ONLY)
                                           .addPoint(aePoint, FocusMeteringAction.MeteringMode.AE_ONLY)
                                           .build());
        } catch (CameraInfoUnavailableException e) {
            Log.d(TAG, "cannot access camera", e);
        }

        return true;
    }