Java tutorial
/* * Copyright 2014 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.movie.mood; import android.Manifest; import android.app.Activity; import android.app.AlertDialog; import android.app.Dialog; import android.app.DialogFragment; import android.app.Fragment; import android.content.Context; import android.content.DialogInterface; import android.content.pm.PackageManager; import android.content.res.Configuration; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.graphics.ImageFormat; import android.graphics.Matrix; import android.graphics.Point; import android.graphics.RectF; import android.graphics.SurfaceTexture; import android.hardware.camera2.CameraAccessException; import android.hardware.camera2.CameraCaptureSession; import android.hardware.camera2.CameraCharacteristics; import android.hardware.camera2.CameraDevice; import android.hardware.camera2.CameraManager; import android.hardware.camera2.CaptureRequest; import android.hardware.camera2.CaptureResult; import android.hardware.camera2.TotalCaptureResult; import android.hardware.camera2.params.StreamConfigurationMap; import android.media.Image; import android.media.ImageReader; import android.os.Bundle; import android.os.Handler; import android.os.HandlerThread; import android.support.annotation.NonNull; import android.support.v13.app.FragmentCompat; import android.support.v4.content.ContextCompat; import android.util.Log; import android.util.Size; import android.util.SparseIntArray; import android.view.LayoutInflater; import android.view.Surface; import android.view.TextureView; import android.view.View; import android.view.View.OnClickListener; import android.view.ViewGroup; import android.widget.Toast; import java.io.File; import java.nio.ByteBuffer; import java.util.Arrays; import java.util.Collections; import java.util.Comparator; import java.util.concurrent.Semaphore; import java.util.concurrent.TimeUnit; public class Camera2BasicFragment extends Fragment implements FragmentCompat.OnRequestPermissionsResultCallback { /** * Conversion from screen rotation to JPEG orientation. */ private static final SparseIntArray ORIENTATIONS = new SparseIntArray(); private static final int REQUEST_CAMERA_PERMISSION = 1; private static final String FRAGMENT_DIALOG = "dialog"; private View mLeftColor; private View mRightColor; static { ORIENTATIONS.append(Surface.ROTATION_0, 90); ORIENTATIONS.append(Surface.ROTATION_90, 0); ORIENTATIONS.append(Surface.ROTATION_180, 270); ORIENTATIONS.append(Surface.ROTATION_270, 180); } /** * Tag for the {@link Log}. */ private static final String TAG = "Camera2BasicFragment"; /** * Camera state: Showing camera preview. */ private static final int STATE_PREVIEW = 0; /** * Camera state: Waiting for the focus to be locked. */ private static final int STATE_WAITING_LOCK = 1; /** * Camera state: Waiting for the exposure to be precapture state. */ private static final int STATE_WAITING_PRECAPTURE = 2; /** * Camera state: Waiting for the exposure state to be something other than precapture. */ private static final int STATE_WAITING_NON_PRECAPTURE = 3; /** * Camera state: Picture was taken. */ private static final int STATE_PICTURE_TAKEN = 4; /** * Max preview width that is guaranteed by Camera2 API */ private static final int MAX_PREVIEW_WIDTH = 1920; /** * Max preview height that is guaranteed by Camera2 API */ private static final int MAX_PREVIEW_HEIGHT = 1080; /** * {@link TextureView.SurfaceTextureListener} handles several lifecycle events on a * {@link TextureView}. */ private final TextureView.SurfaceTextureListener mSurfaceTextureListener = new TextureView.SurfaceTextureListener() { @Override public void onSurfaceTextureAvailable(SurfaceTexture texture, int width, int height) { openCamera(width, height); } @Override public void onSurfaceTextureSizeChanged(SurfaceTexture texture, int width, int height) { configureTransform(width, height); } @Override public boolean onSurfaceTextureDestroyed(SurfaceTexture texture) { return true; } @Override public void onSurfaceTextureUpdated(SurfaceTexture texture) { } }; /** * ID of the current {@link CameraDevice}. */ private String mCameraId; /** * An {@link AutoFitTextureView} for camera preview. */ private AutoFitTextureView mTextureView; /** * A {@link CameraCaptureSession } for camera preview. */ private CameraCaptureSession mCaptureSession; /** * A reference to the opened {@link CameraDevice}. */ private CameraDevice mCameraDevice; /** * The {@link android.util.Size} of camera preview. */ private Size mPreviewSize; /** * {@link CameraDevice.StateCallback} is called when {@link CameraDevice} changes its state. */ private final CameraDevice.StateCallback mStateCallback = new CameraDevice.StateCallback() { @Override public void onOpened(@NonNull CameraDevice cameraDevice) { // This method is called when the camera is opened. We start camera preview here. mCameraOpenCloseLock.release(); mCameraDevice = cameraDevice; createCameraPreviewSession(); } @Override public void onDisconnected(@NonNull CameraDevice cameraDevice) { mCameraOpenCloseLock.release(); cameraDevice.close(); mCameraDevice = null; } @Override public void onError(@NonNull CameraDevice cameraDevice, int error) { mCameraOpenCloseLock.release(); cameraDevice.close(); mCameraDevice = null; Activity activity = getActivity(); if (null != activity) { activity.finish(); } } }; /** * An additional thread for running tasks that shouldn't block the UI. */ private HandlerThread mBackgroundThread; /** * A {@link Handler} for running tasks in the background. */ private Handler mBackgroundHandler; /** * An {@link ImageReader} that handles still image capture. */ private ImageReader mImageReader; /** * This a callback object for the {@link ImageReader}. "onImageAvailable" will be called when a * still image is ready to be saved. */ private final ImageReader.OnImageAvailableListener mOnImageAvailableListener = new ImageReader.OnImageAvailableListener() { ImageSaver imageSaver = new ImageSaver(); @Override public void onImageAvailable(ImageReader reader) { Image image = reader.acquireNextImage(); imageSaver.setImage(image); mBackgroundHandler.removeCallbacksAndMessages(imageSaver); mBackgroundHandler.post(imageSaver); } }; /** * {@link CaptureRequest.Builder} for the camera preview */ private CaptureRequest.Builder mPreviewRequestBuilder; /** * {@link CaptureRequest} generated by {@link #mPreviewRequestBuilder} */ private CaptureRequest mPreviewRequest; /** * The current state of camera state for taking pictures. * * @see #mCaptureCallback */ private int mState = STATE_PREVIEW; /** * A {@link Semaphore} to prevent the app from exiting before closing the camera. */ private Semaphore mCameraOpenCloseLock = new Semaphore(1); /** * Whether the current camera device supports Flash or not. */ private boolean mFlashSupported; /** * A {@link CameraCaptureSession.CaptureCallback} that handles events related to JPEG capture. */ private CameraCaptureSession.CaptureCallback mCaptureCallback = new CameraCaptureSession.CaptureCallback() { private void process(CaptureResult result) { switch (mState) { case STATE_PREVIEW: { // We have nothing to do when the camera preview is working normally. break; } case STATE_WAITING_LOCK: { Integer afState = result.get(CaptureResult.CONTROL_AF_STATE); if (afState == null) { // captureStillPicture(); } else 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 Integer aeState = result.get(CaptureResult.CONTROL_AE_STATE); if (aeState == null || aeState == CaptureResult.CONTROL_AE_STATE_CONVERGED) { mState = STATE_PICTURE_TAKEN; // captureStillPicture(); } else { runPrecaptureSequence(); } } break; } case STATE_WAITING_PRECAPTURE: { // CONTROL_AE_STATE can be null on some devices Integer aeState = result.get(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; } break; } case STATE_WAITING_NON_PRECAPTURE: { // CONTROL_AE_STATE can be null on some devices Integer aeState = result.get(CaptureResult.CONTROL_AE_STATE); if (aeState == null || aeState != CaptureResult.CONTROL_AE_STATE_PRECAPTURE) { mState = STATE_PICTURE_TAKEN; // captureStillPicture(); } break; } } } @Override public void onCaptureProgressed(@NonNull CameraCaptureSession session, @NonNull CaptureRequest request, @NonNull CaptureResult partialResult) { process(partialResult); } @Override public void onCaptureCompleted(@NonNull CameraCaptureSession session, @NonNull CaptureRequest request, @NonNull TotalCaptureResult result) { process(result); } }; public void setDebugColors(int left, int right) { mLeftColor.setBackgroundColor(left); mRightColor.setBackgroundColor(right); } /** * Shows a {@link Toast} on the UI thread. * * @param text The message to show */ private void showToast(final String text) { final Activity activity = getActivity(); if (activity != null) { activity.runOnUiThread(new Runnable() { @Override public void run() { Toast.makeText(activity, text, Toast.LENGTH_SHORT).show(); } }); } } /** * Given {@code choices} of {@code Size}s supported by a camera, choose the smallest one that * is at least as large as the respective texture view size, and that is at most as large as the * respective max size, and whose aspect ratio matches with the specified value. If such size * doesn't exist, choose the largest one that is at most as large as the respective max size, * and whose aspect ratio matches with the specified value. * * @param choices The list of sizes that the camera supports for the intended output * class * @param textureViewWidth The width of the texture view relative to sensor coordinate * @param textureViewHeight The height of the texture view relative to sensor coordinate * @param maxWidth The maximum width that can be chosen * @param maxHeight The maximum height that can be chosen * @param aspectRatio The aspect ratio * @return The optimal {@code Size}, or an arbitrary one if none were big enough */ private static Size chooseOptimalSize(Size[] choices, int textureViewWidth, int textureViewHeight, int maxWidth, int maxHeight, Size aspectRatio) { // // Collect the supported resolutions that are at least as big as the preview Surface // List<Size> bigEnough = new ArrayList<>(); // // Collect the supported resolutions that are smaller than the preview Surface // List<Size> notBigEnough = new ArrayList<>(); // int w = aspectRatio.getWidth(); // int h = aspectRatio.getHeight(); // for (Size option : choices) { // if (option.getWidth() <= maxWidth && option.getHeight() <= maxHeight && // option.getHeight() == option.getWidth() * h / w) { // if (option.getWidth() >= textureViewWidth && option.getHeight() >= textureViewHeight) { // bigEnough.add(option); // } else { // notBigEnough.add(option); // } // } // } // // // Pick the smallest of those big enough. If there is no one big enough, pick the // // largest of those not big enough. // if (bigEnough.size() > 0) { // return Collections.min(bigEnough, new CompareSizesByArea()); // } else if (notBigEnough.size() > 0) { // return Collections.max(notBigEnough, new CompareSizesByArea()); // } else { // Log.e(TAG, "Couldn't find any suitable preview size"); // return choices[0]; // } System.out.println("choosing preview size " + choices[choices.length - 1]); return choices[choices.length - 1]; } public static Camera2BasicFragment newInstance() { return new Camera2BasicFragment(); } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { return inflater.inflate(R.layout.fragment_camera2_basic, container, false); } @Override public void onViewCreated(final View view, Bundle savedInstanceState) { mTextureView = (AutoFitTextureView) view.findViewById(R.id.texture); mLeftColor = view.findViewById(R.id.left); mRightColor = view.findViewById(R.id.right); } @Override public void onResume() { super.onResume(); startBackgroundThread(); // When the screen is turned off and turned back on, the SurfaceTexture is already // available, and "onSurfaceTextureAvailable" will not be called. In that case, we can open // a camera and start preview from here (otherwise, we wait until the surface is ready in // the SurfaceTextureListener). if (mTextureView.isAvailable()) { openCamera(mTextureView.getWidth(), mTextureView.getHeight()); } else { mTextureView.setSurfaceTextureListener(mSurfaceTextureListener); } } @Override public void onPause() { closeCamera(); stopBackgroundThread(); super.onPause(); } private void requestCameraPermission() { if (FragmentCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.CAMERA)) { new ConfirmationDialog().show(getChildFragmentManager(), FRAGMENT_DIALOG); } else { FragmentCompat.requestPermissions(this, new String[] { Manifest.permission.CAMERA }, REQUEST_CAMERA_PERMISSION); } } @Override public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) { if (requestCode == REQUEST_CAMERA_PERMISSION) { if (grantResults.length != 1 || grantResults[0] != PackageManager.PERMISSION_GRANTED) { ErrorDialog.newInstance("give me the permission").show(getChildFragmentManager(), FRAGMENT_DIALOG); } } else { super.onRequestPermissionsResult(requestCode, permissions, grantResults); } } /** * Sets up member variables related to camera. * * @param width The width of available size for camera preview * @param height The height of available size for camera preview */ private void setUpCameraOutputs(int width, int height) { Activity activity = getActivity(); CameraManager manager = (CameraManager) activity.getSystemService(Context.CAMERA_SERVICE); try { for (String cameraId : manager.getCameraIdList()) { CameraCharacteristics characteristics = manager.getCameraCharacteristics(cameraId); // We don't use a front facing camera in this sample. Integer facing = characteristics.get(CameraCharacteristics.LENS_FACING); if (facing != null && facing == CameraCharacteristics.LENS_FACING_FRONT) { continue; } StreamConfigurationMap map = characteristics .get(CameraCharacteristics.SCALER_STREAM_CONFIGURATION_MAP); if (map == null) { continue; } int imageFormat = ImageFormat.JPEG; // For still image captures, we use the smallest available size. Size smallest = Collections.min(Arrays.asList(map.getOutputSizes(imageFormat)), new CompareSizesByArea()); mImageReader = ImageReader.newInstance(smallest.getWidth(), smallest.getHeight(), imageFormat, /*maxImages*/2); mImageReader.setOnImageAvailableListener(mOnImageAvailableListener, mBackgroundHandler); // Find out if we need to swap dimension to get the preview size relative to sensor // coordinate. int displayRotation = activity.getWindowManager().getDefaultDisplay().getRotation(); //noinspection ConstantConditions /* Orientation of the camera sensor */ final int mSensorOrientation = characteristics.get(CameraCharacteristics.SENSOR_ORIENTATION); boolean swappedDimensions = false; switch (displayRotation) { case Surface.ROTATION_0: case Surface.ROTATION_180: if (mSensorOrientation == 90 || mSensorOrientation == 270) { swappedDimensions = true; } break; case Surface.ROTATION_90: case Surface.ROTATION_270: if (mSensorOrientation == 0 || mSensorOrientation == 180) { swappedDimensions = true; } break; default: Log.e(TAG, "Display rotation is invalid: " + displayRotation); } Point displaySize = new Point(); activity.getWindowManager().getDefaultDisplay().getSize(displaySize); int rotatedPreviewWidth = width; int rotatedPreviewHeight = height; int maxPreviewWidth = displaySize.x; int maxPreviewHeight = displaySize.y; if (swappedDimensions) { rotatedPreviewWidth = height; rotatedPreviewHeight = width; maxPreviewWidth = displaySize.y; maxPreviewHeight = displaySize.x; } if (maxPreviewWidth > MAX_PREVIEW_WIDTH) { maxPreviewWidth = MAX_PREVIEW_WIDTH; } if (maxPreviewHeight > MAX_PREVIEW_HEIGHT) { maxPreviewHeight = MAX_PREVIEW_HEIGHT; } // Danger, W.R.! Attempting to use too large a preview size could exceed the camera // bus' bandwidth limitation, resulting in gorgeous previews but the storage of // garbage capture data. mPreviewSize = chooseOptimalSize(map.getOutputSizes(SurfaceTexture.class), rotatedPreviewWidth, rotatedPreviewHeight, maxPreviewWidth, maxPreviewHeight, smallest); // We fit the aspect ratio of TextureView to the size of preview we picked. int orientation = getResources().getConfiguration().orientation; if (orientation == Configuration.ORIENTATION_LANDSCAPE) { mTextureView.setAspectRatio(mPreviewSize.getWidth(), mPreviewSize.getHeight()); } else { mTextureView.setAspectRatio(mPreviewSize.getHeight(), mPreviewSize.getWidth()); } // Check if the flash is supported. Boolean available = characteristics.get(CameraCharacteristics.FLASH_INFO_AVAILABLE); mFlashSupported = available == null ? false : available; mCameraId = cameraId; return; } } catch (CameraAccessException e) { e.printStackTrace(); } catch (NullPointerException e) { // Currently an NPE is thrown when the Camera2API is used but not supported on the // device this code runs. ErrorDialog.newInstance("camera error!!").show(getChildFragmentManager(), FRAGMENT_DIALOG); e.printStackTrace(); } } /** * Opens the camera specified by {@link Camera2BasicFragment#mCameraId}. */ private void openCamera(int width, int height) { if (ContextCompat.checkSelfPermission(getActivity(), Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) { requestCameraPermission(); return; } setUpCameraOutputs(width, height); configureTransform(width, height); Activity activity = getActivity(); CameraManager manager = (CameraManager) activity.getSystemService(Context.CAMERA_SERVICE); try { if (!mCameraOpenCloseLock.tryAcquire(2500, TimeUnit.MILLISECONDS)) { throw new RuntimeException("Time out waiting to lock camera opening."); } manager.openCamera(mCameraId, mStateCallback, mBackgroundHandler); } catch (CameraAccessException e) { e.printStackTrace(); } catch (InterruptedException e) { throw new RuntimeException("Interrupted while trying to lock camera opening.", e); } } /** * Closes the current {@link CameraDevice}. */ private void closeCamera() { try { mCameraOpenCloseLock.acquire(); if (null != mCaptureSession) { mCaptureSession.close(); mCaptureSession = null; } if (null != mCameraDevice) { mCameraDevice.close(); mCameraDevice = null; } if (null != mImageReader) { mImageReader.close(); mImageReader = null; } } catch (InterruptedException e) { throw new RuntimeException("Interrupted while trying to lock camera closing.", e); } finally { mCameraOpenCloseLock.release(); } } /** * Starts a background thread and its {@link Handler}. */ private void startBackgroundThread() { mBackgroundThread = new HandlerThread("CameraBackground"); mBackgroundThread.start(); mBackgroundHandler = new Handler(mBackgroundThread.getLooper()); } /** * Stops the background thread and its {@link Handler}. */ private void stopBackgroundThread() { mBackgroundThread.quitSafely(); try { mBackgroundThread.join(); mBackgroundThread = null; mBackgroundHandler = null; } catch (InterruptedException e) { e.printStackTrace(); } } /** * Creates a new {@link CameraCaptureSession} for camera preview. */ private void createCameraPreviewSession() { try { SurfaceTexture texture = mTextureView.getSurfaceTexture(); assert texture != null; // We configure the size of default buffer to be the size of camera preview we want. texture.setDefaultBufferSize(mPreviewSize.getWidth(), mPreviewSize.getHeight()); // This is the output Surface we need to start preview. Surface surface = new Surface(texture); // We set up a CaptureRequest.Builder with the output Surface. mPreviewRequestBuilder = mCameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW); mPreviewRequestBuilder.addTarget(surface); mPreviewRequestBuilder.addTarget(mImageReader.getSurface()); // Here, we create a CameraCaptureSession for camera preview. mCameraDevice.createCaptureSession(Arrays.asList(surface, mImageReader.getSurface()), new CameraCaptureSession.StateCallback() { @Override public void onConfigured(@NonNull CameraCaptureSession cameraCaptureSession) { // The camera is already closed if (null == mCameraDevice) { return; } // When the session is ready, we start displaying the preview. mCaptureSession = cameraCaptureSession; try { // Auto focus should be continuous for camera preview. mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_MODE, CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE); // Flash is automatically enabled when necessary. setAutoFlash(mPreviewRequestBuilder); // Finally, we start displaying the camera preview. mPreviewRequest = mPreviewRequestBuilder.build(); mCaptureSession.setRepeatingRequest(mPreviewRequest, mCaptureCallback, mBackgroundHandler); } catch (CameraAccessException e) { e.printStackTrace(); } } @Override public void onConfigureFailed(@NonNull CameraCaptureSession cameraCaptureSession) { showToast("Failed"); } }, null); } catch (CameraAccessException e) { e.printStackTrace(); } } /** * Configures the necessary {@link android.graphics.Matrix} transformation to `mTextureView`. * This method should be called after the camera preview size is determined in * setUpCameraOutputs and also the size of `mTextureView` is fixed. * * @param viewWidth The width of `mTextureView` * @param viewHeight The height of `mTextureView` */ private void configureTransform(int viewWidth, int viewHeight) { Activity activity = getActivity(); if (null == mTextureView || null == mPreviewSize || null == activity) { return; } int rotation = activity.getWindowManager().getDefaultDisplay().getRotation(); Matrix matrix = new Matrix(); RectF viewRect = new RectF(0, 0, viewWidth, viewHeight); RectF bufferRect = new RectF(0, 0, mPreviewSize.getHeight(), mPreviewSize.getWidth()); float centerX = viewRect.centerX(); float centerY = viewRect.centerY(); if (Surface.ROTATION_90 == rotation || Surface.ROTATION_270 == rotation) { bufferRect.offset(centerX - bufferRect.centerX(), centerY - bufferRect.centerY()); matrix.setRectToRect(viewRect, bufferRect, Matrix.ScaleToFit.FILL); float scale = Math.max((float) viewHeight / mPreviewSize.getHeight(), (float) viewWidth / mPreviewSize.getWidth()); matrix.postScale(scale, scale, centerX, centerY); matrix.postRotate(90 * (rotation - 2), centerX, centerY); } else if (Surface.ROTATION_180 == rotation) { matrix.postRotate(180, centerX, centerY); } mTextureView.setTransform(matrix); } /** * Run the precapture sequence for capturing a still image. This method should be called when * we get a response in {@link #mCaptureCallback} from lockFocus(). */ private void runPrecaptureSequence() { try { // This is how to tell the camera to trigger. mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AE_PRECAPTURE_TRIGGER, CaptureRequest.CONTROL_AE_PRECAPTURE_TRIGGER_START); // Tell #mCaptureCallback to wait for the precapture sequence to be set. mState = STATE_WAITING_PRECAPTURE; mCaptureSession.capture(mPreviewRequestBuilder.build(), mCaptureCallback, mBackgroundHandler); } catch (CameraAccessException e) { e.printStackTrace(); } } private void setAutoFlash(CaptureRequest.Builder requestBuilder) { if (mFlashSupported) { requestBuilder.set(CaptureRequest.CONTROL_AE_MODE, CaptureRequest.CONTROL_AE_MODE_ON_AUTO_FLASH); } } /** * Saves a JPEG {@link Image} into the specified {@link File}. */ private class ImageSaver implements Runnable { /** * The JPEG image */ private Image mImage; private byte[] bytes; public ImageSaver() { } @Override public void run() { if (onImageCapturedListener == null) { mImage.close(); return; } ByteBuffer buffer = mImage.getPlanes()[0].getBuffer(); int bufferSize = buffer.remaining(); if (bytes == null || bytes.length < bufferSize) { bytes = new byte[bufferSize]; } buffer.get(bytes, 0, bufferSize); try { Bitmap mBitmap = BitmapFactory.decodeByteArray(bytes, 0, bufferSize); onImageCapturedListener.onImageCaptured(mBitmap); //TODO post to another thread } finally { mImage.close(); } } public void setImage(Image mImage) { this.mImage = mImage; } } OnImageCapturedListener onImageCapturedListener; public void setOnImageCapturedListener(OnImageCapturedListener onImageCapturedListener) { this.onImageCapturedListener = onImageCapturedListener; } public interface OnImageCapturedListener { void onImageCaptured(Bitmap bitmap); } /** * Compares two {@code Size}s based on their areas. */ static class CompareSizesByArea implements Comparator<Size> { @Override public int compare(Size lhs, Size rhs) { // We cast here to ensure the multiplications won't overflow return Long.signum((long) lhs.getWidth() * lhs.getHeight() - (long) rhs.getWidth() * rhs.getHeight()); } } /** * Shows an error message dialog. */ public static class ErrorDialog extends DialogFragment { private static final String ARG_MESSAGE = "message"; public static ErrorDialog newInstance(String message) { ErrorDialog dialog = new ErrorDialog(); Bundle args = new Bundle(); args.putString(ARG_MESSAGE, message); dialog.setArguments(args); return dialog; } @Override public Dialog onCreateDialog(Bundle savedInstanceState) { final Activity activity = getActivity(); return new AlertDialog.Builder(activity).setMessage(getArguments().getString(ARG_MESSAGE)) .setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialogInterface, int i) { activity.finish(); } }).create(); } } /** * Shows OK/Cancel confirmation dialog about camera permission. */ public static class ConfirmationDialog extends DialogFragment { @Override public Dialog onCreateDialog(Bundle savedInstanceState) { final Fragment parent = getParentFragment(); return new AlertDialog.Builder(getActivity()).setMessage("Give me the permission!") .setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { FragmentCompat.requestPermissions(parent, new String[] { Manifest.permission.CAMERA }, REQUEST_CAMERA_PERMISSION); } }).setNegativeButton(android.R.string.cancel, new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { Activity activity = parent.getActivity(); if (activity != null) { activity.finish(); } } }).create(); } } }