I branched form an example of Google Camera2Basic and changed it to use CaptureRequest.CONTROL_AF_MODE_AUTO instead of CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE
You can take a project from git and test it - https://github.com/pinhassi/android-Camera2Basic
Or just add this to Camera2BasicFragment :
private static final long LOCK_FOCUS_DELAY_ON_FOCUSED = 5000; private static final long LOCK_FOCUS_DELAY_ON_UNFOCUSED = 1000; private Integer mLastAfState = null; private Handler mUiHandler = new Handler(); // UI handler private Runnable mLockAutoFocusRunnable = new Runnable() { @Override public void run() { lockAutoFocus(); } }; public void lockAutoFocus() { try { // This is how to tell the camera to lock focus. mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_TRIGGER, CameraMetadata.CONTROL_AF_TRIGGER_START); CaptureRequest captureRequest = mPreviewRequestBuilder.build(); mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_TRIGGER, null); // prevent CONTROL_AF_TRIGGER_START from calling over and over again mCaptureSession.capture(captureRequest, mCaptureCallback, mBackgroundHandler); } catch (CameraAccessException e) { e.printStackTrace(); } } /** * * @return */ private float getMinimumFocusDistance() { if (mCameraId == null) return 0; Float minimumLens = null; try { CameraManager manager = (CameraManager) getActivity().getSystemService(Context.CAMERA_SERVICE); CameraCharacteristics c = manager.getCameraCharacteristics(mCameraId); minimumLens = c.get(CameraCharacteristics.LENS_INFO_MINIMUM_FOCUS_DISTANCE); } catch (Exception e) { Log.e(TAG, "isHardwareLevelSupported Error", e); } if (minimumLens != null) return minimumLens; return 0; } /** * * @return */ private boolean isAutoFocusSupported() { return isHardwareLevelSupported(CameraCharacteristics.INFO_SUPPORTED_HARDWARE_LEVEL_LEGACY) || getMinimumFocusDistance() > 0; } // Returns true if the device supports the required hardware level, or better. @TargetApi(Build.VERSION_CODES.LOLLIPOP) private boolean isHardwareLevelSupported(int requiredLevel) { boolean res = false; if (mCameraId == null) return res; try { CameraManager manager = (CameraManager) getActivity().getSystemService(Context.CAMERA_SERVICE); CameraCharacteristics cameraCharacteristics = manager.getCameraCharacteristics(mCameraId); int deviceLevel = cameraCharacteristics.get(CameraCharacteristics.INFO_SUPPORTED_HARDWARE_LEVEL); switch (deviceLevel) { case CameraCharacteristics.INFO_SUPPORTED_HARDWARE_LEVEL_3: Log.d(TAG, "Camera support level: INFO_SUPPORTED_HARDWARE_LEVEL_3"); break; case CameraCharacteristics.INFO_SUPPORTED_HARDWARE_LEVEL_FULL: Log.d(TAG, "Camera support level: INFO_SUPPORTED_HARDWARE_LEVEL_FULL"); break; case CameraCharacteristics.INFO_SUPPORTED_HARDWARE_LEVEL_LEGACY: Log.d(TAG, "Camera support level: INFO_SUPPORTED_HARDWARE_LEVEL_LEGACY"); break; case CameraCharacteristics.INFO_SUPPORTED_HARDWARE_LEVEL_LIMITED: Log.d(TAG, "Camera support level: INFO_SUPPORTED_HARDWARE_LEVEL_LIMITED"); break; default: Log.d(TAG, "Unknown INFO_SUPPORTED_HARDWARE_LEVEL: " + deviceLevel); break; } if (deviceLevel == CameraCharacteristics.INFO_SUPPORTED_HARDWARE_LEVEL_LEGACY) { res = requiredLevel == deviceLevel; } else { // deviceLevel is not LEGACY, can use numerical sort res = requiredLevel <= deviceLevel; } } catch (Exception e) { Log.e(TAG, "isHardwareLevelSupported Error", e); } return res; }
Then add to the STATE_PREVIEW block:
case STATE_PREVIEW: { // We have nothing to do when the camera preview is working normally. // TODO: handle auto focus Integer afState = result.get(CaptureResult.CONTROL_AF_STATE); if (afState != null && !afState.equals(mLastAfState)) { switch (afState) { case CaptureResult.CONTROL_AF_STATE_INACTIVE: Log.d(TAG, "CaptureResult.CONTROL_AF_STATE_INACTIVE"); lockAutoFocus(); break; case CaptureResult.CONTROL_AF_STATE_ACTIVE_SCAN: Log.d(TAG, "CaptureResult.CONTROL_AF_STATE_ACTIVE_SCAN"); break; case CaptureResult.CONTROL_AF_STATE_FOCUSED_LOCKED: Log.d(TAG, "CaptureResult.CONTROL_AF_STATE_FOCUSED_LOCKED"); mUiHandler.removeCallbacks(mLockAutoFocusRunnable); mUiHandler.postDelayed(mLockAutoFocusRunnable, LOCK_FOCUS_DELAY_ON_FOCUSED); break; case CaptureResult.CONTROL_AF_STATE_NOT_FOCUSED_LOCKED: mUiHandler.removeCallbacks(mLockAutoFocusRunnable); mUiHandler.postDelayed(mLockAutoFocusRunnable, LOCK_FOCUS_DELAY_ON_UNFOCUSED); Log.d(TAG, "CaptureResult.CONTROL_AF_STATE_NOT_FOCUSED_LOCKED"); break; case CaptureResult.CONTROL_AF_STATE_PASSIVE_UNFOCUSED: mUiHandler.removeCallbacks(mLockAutoFocusRunnable); //mUiHandler.postDelayed(mLockAutoFocusRunnable, LOCK_FOCUS_DELAY_ON_UNFOCUSED); Log.d(TAG, "CaptureResult.CONTROL_AF_STATE_PASSIVE_UNFOCUSED"); break; case CaptureResult.CONTROL_AF_STATE_PASSIVE_SCAN: Log.d(TAG, "CaptureResult.CONTROL_AF_STATE_PASSIVE_SCAN"); break; case CaptureResult.CONTROL_AF_STATE_PASSIVE_FOCUSED: mUiHandler.removeCallbacks(mLockAutoFocusRunnable); //mUiHandler.postDelayed(mLockAutoFocusRunnable, LOCK_FOCUS_DELAY_ON_FOCUSED); Log.d(TAG, "CaptureResult.CONTROL_AF_STATE_PASSIVE_FOCUSED"); break; } } mLastAfState = afState; break; }
And replace all occurrences:
mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_MODE, CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE);
WITH
if (isAutoFocusSupported()) mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_MODE, CaptureRequest.CONTROL_AF_MODE_AUTO); else mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_MODE, CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE);