java - 运行相机服务时 takePicture 失败

Question

我尝试在后台运行相机服务，服务启动后我立即收到错误takePicture failed。我是 Android 新手，Stackoverflow 新手，也不是一个好的程序员。

我已经添加了正确的权限，并且该服务也已在 list 文件中声明。包 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;
    }
}

I got the SourceCode from here: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 只是一个异步任务，它保存图片，我认为这没有问题。

希望大家能够帮助我。

祝你编码愉快!

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)

Answer 1

只需添加SurfaceTexture st = new SurfaceTexture(MODE_PRIVATE); mCamera.setPreviewTexture(st);在mCamera.startPreview();

之前