运行Camera Service时takePicture失败
我试图在后台运行相机服务，在服务启动后不久我得到一个错误takePicture failed 。 我是Android的新手，也是Stackoverflow的新手，也不是一个优秀的程序员。
我已添加了正确的权限，并且该服务也已在清单文件中声明。 package com.example.nevii.camera;
import android.app.Service; import android.content.Intent; import android.hardware.Camera; import android.hardware.Camera.Parameters; import android.os.IBinder; import android.view.SurfaceHolder; import android.view.SurfaceView; import android.widget.Toast; import java.io.IOException; public class CameraService extends Service { //Camera variables //a surface holder private SurfaceHolder sHolder; //a variable to control the camera private Camera mCamera; //the camera parameters private Parameters parameters; private boolean safeToTakePicture = false; /** Called when the activity is first created. */ @Override public void onCreate() { super.onCreate(); } @Override public int onStartCommand(Intent intent, int flags, int startId) { // TODO Auto-generated method stub super.onStartCommand(intent, flags, startId); Toast.makeText(getBaseContext(), "onStartCommand", Toast.LENGTH_SHORT).show(); mCamera = Camera.open(1); mCamera.setDisplayOrientation(90); SurfaceView sv = new SurfaceView(getApplicationContext()); try { mCamera.setPreviewDisplay(sv.getHolder()); parameters = mCamera.getParameters(); //set camera parameters mCamera.setParameters(parameters); mCamera.startPreview(); safeToTakePicture = true; takePic(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); //stop the preview mCamera.stopPreview(); mCamera.setPreviewCallback(null); //release the camera mCamera.release(); //unbind the camera from this object mCamera = null; } //Get a surface sHolder = sv.getHolder(); //tells Android that this surface will have its data constantly replaced sHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS); return START_STICKY; } public void takePic(){ Camera.PictureCallback mCall = new Camera.PictureCallback() { public void onPictureTaken(byte[] data, Camera camera) { //decode the data obtained by the camera into a Bitmap MyCamera myCamera = new MyCamera(); myCamera.SavePicture(data); //stop the preview mCamera.stopPreview(); mCamera.setPreviewCallback(null); //release the camera mCamera.release(); //unbind the camera from this object mCamera = null; } }; mCamera.takePicture(null, null, mCall); Toast.makeText(getApplicationContext(),"Pic taken",Toast.LENGTH_LONG).show(); } @Override public IBinder onBind(Intent intent) { // TODO Auto-generated method stub return null; } }
我从这里得到了SourceCode： http ： //androideasylessons.blogspot.ch/2012/09/capture-image-without-surface-view-as.html
在MainActivity中，我使用以下命令启动了服务： startService(new Intent(this, CameraService.class));
myCamera.SavePicture只是一个Asynchtask，它保存了Picture，我认为没有问题。
我希望你们能帮助我。
快乐的编码！
更新Logcat错误：
03-03 09:04:46.150 27530-27530/com.example.nevii.videocam D/Camera﹕ app passed NULL surface 03-03 09:04:46.153 27530-27530/com.example.nevii.videocam D/AndroidRuntime﹕ Shutting down VM 03-03 09:04:46.154 27530-27530/com.example.nevii.videocam E/AndroidRuntime﹕ FATAL EXCEPTION: main Process: com.example.nevii.videocam, PID: 27530 java.lang.RuntimeException: Unable to start service com.example.nevii.videocam.CameraService@3f53f37f with Intent { cmp=com.example.nevii.videocam/.CameraService }: java.lang.RuntimeException: takePicture failed at android.app.ActivityThread.handleServiceArgs(ActivityThread.java:2881) at android.app.ActivityThread.access$2100(ActivityThread.java:144) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1376) at android.os.Handler.dispatchMessage(Handler.java:102) at android.os.Looper.loop(Looper.java:135) at android.app.ActivityThread.main(ActivityThread.java:5221) at java.lang.reflect.Method.invoke(Native Method) at java.lang.reflect.Method.invoke(Method.java:372) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694) Caused by: java.lang.RuntimeException: takePicture failed at android.hardware.Camera.native_takePicture(Native Method) at android.hardware.Camera.takePicture(Camera.java:1436) at android.hardware.Camera.takePicture(Camera.java:1381) at com.example.nevii.videocam.CameraService.takePic(CameraService.java:101) at com.example.nevii.videocam.CameraService.onStartCommand(CameraService.java:57) at android.app.ActivityThread.handleServiceArgs(ActivityThread.java:2864) at android.app.ActivityThread.access$2100(ActivityThread.java:144) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1376) at android.os.Handler.dispatchMessage(Handler.java:102) at android.os.Looper.loop(Looper.java:135) at android.app.ActivityThread.main(ActivityThread.java:5221) at java.lang.reflect.Method.invoke(Native Method) at java.lang.reflect.Method.invoke(Method.java:372) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
只需添加SurfaceTexture st = new SurfaceTexture(MODE_PRIVATE); mCamera.setPreviewTexture(st); SurfaceTexture st = new SurfaceTexture(MODE_PRIVATE); mCamera.setPreviewTexture(st); 在mCamera.startPreview();之前mCamera.startPreview();