Android实现极简打开摄像头 Android实现极简打开摄像头

很多时候忘记Android摄像头如何打开，查看google文档的话，发现太复杂（只是单纯的想打开摄像头而已，不想添加那么多设置，添加那么功能），很多博客也是对官方文档的小修小改，连方法名都一样，因此，我决定完成Android相机最简单的打开摄像头（仅仅打开）。很久没用忘掉的话，打开链接复制粘贴一下就完事了。
AndroidManifest.xml设置CAMERA权限后，在代码中还要设置权限检查，但是因为我连权限检查都懒得加了，装好后直接在手机系统里手动允许权限。
Camera1（已废弃）：
【Android实现极简打开摄像头】xml中使用SurfaceView作为预览View

MainActivity:

public class MainActivity extends AppCompatActivity implements SurfaceHolder.Callback{private SurfaceHolder holder; private Camera camera; @Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState); requestWindowFeature(Window.FEATURE_NO_TITLE); getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN); setContentView(R.layout.activity_main); SurfaceView surfaceView = findViewById(R.id.surfaceView); holder = surfaceView.getHolder(); holder.addCallback(this); }@Overridepublic void surfaceCreated(SurfaceHolder holder) {if(camera == null){try {camera = Camera.open(Camera.CameraInfo.CAMERA_FACING_BACK); camera.setPreviewDisplay(holder); camera.startPreview(); Camera.Parameters parameters = camera.getParameters(); parameters.setFocusMode(Camera.Parameters.FOCUS_MODE_AUTO); parameters.setFlashMode(Camera.Parameters.FLASH_MODE_AUTO); camera.setParameters(parameters); camera.setDisplayOrientation(90); }catch (Exception e){e.printStackTrace(); }}}}

这样就完成了最简单的打开摄像头并在手机中出现画面。（代码里去掉2个接口中未实现的方法）
Camera2
Android 5.0（API 21）以后，谷歌就决定废弃原有的Camera API改用Camera2 API，因为功能更强大

文章图片

xml使用TextureView作为预览（其实SurfaceView也行，官方的Demo是用TextureView的一个子类）：

MainActivity:

public class MainActivity extends AppCompatActivity implements TextureView.SurfaceTextureListener {private TextureView textureView; private CaptureRequest.Builder builder; @Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); textureView = findViewById(R.id.surfaceView); textureView.setSurfaceTextureListener(this); }@Overridepublic void onSurfaceTextureAvailable(final SurfaceTexture surface, int width, int height) {CameraManager manager = (CameraManager) getSystemService(CAMERA_SERVICE); if (ActivityCompat.checkSelfPermission(MainActivity.this, Manifest.permission.CAMERA)!= PackageManager.PERMISSION_GRANTED) {return; }try {manager.openCamera("0", new CameraDevice.StateCallback() {@Overridepublic void onOpened(@NonNull CameraDevice camera) {try {SurfaceTexture surfaceTexture = textureView.getSurfaceTexture(); surfaceTexture.setDefaultBufferSize(1440,1080); Surface surface = new Surface(surfaceTexture); builder = camera.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW); builder.addTarget(surface); camera.createCaptureSession(Arrays.asList(surface),new CameraCaptureSession.StateCallback() {@Overridepublic void onConfigured(@NonNull CameraCaptureSession session) {try {session.setRepeatingRequest(builder.build(), null, null); } catch (CameraAccessException e) {e.printStackTrace(); }}@Overridepublic void onConfigureFailed(@NonNull CameraCaptureSession session) {}}, null); } catch (CameraAccessException e) {e.printStackTrace(); }}@Overridepublic void onDisconnected(@NonNull CameraDevice camera) {}@Overridepublic void onError(@NonNull CameraDevice camera, int error) {}}, null); } catch (CameraAccessException e) {e.printStackTrace(); }}}

这样就成功使用Camera2的API打开并预览了（代码里去掉3个接口中未实现的方法）
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持脚本之家。