我的应用程序启动时,如何在没有预览的情况下从相机拍照？

Question

现在我想要的只是一个应用程序,只需在启动时从相机拍摄照片.没有布局,没有相机预览......没有,只是一个简单的应用程序图标来启动应用程序.一旦启动,相机应该拍照.

这是预览图像,我不想在我的应用程序中显示.我只是想让我的应用程序点击图片中包围的拍照按钮:

拍完照片后,我需要将照片保存在照片库中.

有人能指导我吗？谢谢

这是我在仿真器和设备上尝试过的一些代码.

import java.io.IOException;
import android.app.Activity;
import android.hardware.Camera;
import android.hardware.Camera.PictureCallback;
import android.hardware.Camera.ShutterCallback;
import android.os.Bundle;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ImageButton;

public class Main extends Activity implements SurfaceHolder.Callback{

    private Camera camera;
     private ImageButton cameraClick;
     private SurfaceHolder mHolder; 

    /** Called when the activity is first created. */
     @Override
     public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);

      SurfaceView surfaceView = (SurfaceView)findViewById(R.id.surfaceView1);
      mHolder = surfaceView.getHolder();
      mHolder.addCallback(this);
      mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);  

      cameraClick = (ImageButton) findViewById(R.id.cameraClick);
      cameraClick.setOnClickListener( new OnClickListener() {
       public void onClick(View v)
       {
            camera.takePicture(shutterCallback, rawCallback,jpegCallback);
       }
      });  





      }

     // Handles when shutter open
     ShutterCallback shutterCallback = new ShutterCallback()
     {
      public void onShutter()
      {   

      }
     };

     /** Handles data for raw picture */
     PictureCallback rawCallback = new PictureCallback()
     {
      public void onPictureTaken(byte[] data, Camera camera)
      {   

      }
     }; 

     /** Handles data for jpeg picture */
     PictureCallback jpegCallback = new PictureCallback()
    {
      public void onPictureTaken(byte[] data, Camera camera)
    {
       // we do something using return byte[] of taken image.
      }
     };

     @Override
     public void surfaceChanged(SurfaceHolder holder,int format,int width,int height)
    {

      // Set camera preview size,orientation,rotation using parameters 

    Camera.Parameters parameters = camera.getParameters();
            parameters.set("orientation", "portrait");
            camera.setParameters(parameters);
             camera.startPreview();       

     }

     @Override
     public void surfaceCreated(SurfaceHolder holder)
    {
      camera = Camera.open();
             try {
        camera.setPreviewDisplay(holder);
       }
    catch (IOException e)
    {
        e.printStackTrace();
       }

     }

     @Override
     public void surfaceDestroyed(SurfaceHolder holder)
    {
      camera.stopPreview();
             camera.release();
            camera = null; 

     }

}

现在我能够听到图片点击按钮,同时点击模拟器和设备.现在我想保存图片.任何线索？

Answer 1

使用以下代码.它经过测试并为我工作.任何问题请随时发表评论.

private void takeSnapShots()
{
      Toast.makeText(getApplicationContext(), "Image snapshot   Started",Toast.LENGTH_SHORT).show();
     // here below "this" is activity context.  
 SurfaceView surface = new SurfaceView(this);
    Camera camera = Camera.open();
    try {
        camera.setPreviewDisplay(surface.getHolder());
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    camera.startPreview();
    camera.takePicture(null,null,jpegCallback);
}


 /** picture call back */
PictureCallback jpegCallback = new PictureCallback() {
public void onPictureTaken(byte[] data, Camera camera) 
{
    FileOutputStream outStream = null;
    try {
  String dir_path = "";// set your directory path here
        outStream = new FileOutputStream(dir_path+File.separator+image_name+no_pics+".jpg");    
        outStream.write(data);
        outStream.close();
        Log.d(TAG, "onPictureTaken - wrote bytes: " + data.length);
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    } finally 
    {
        camera.stopPreview();
        camera.release();
        camera = null;
        Toast.makeText(getApplicationContext(), "Image snapshot Done",Toast.LENGTH_LONG).show();


    }
    Log.d(TAG, "onPictureTaken - jpeg");
}
};

Answer 2

从API级别11 开始,添加了SurfaceTexture.有了它,不再需要SurfaceView.我用三星Galaxy S3 Neo测试了以下代码.

mCamera = Camera.open();
try {
    mCamera.setPreviewTexture(new SurfaceTexture(10));
} catch (IOException e1) {
    Log.e(Version.APP_ID, e1.getMessage());
}

Parameters params = mCamera.getParameters();
params.setPreviewSize(640, 480);
params.setFlashMode(Camera.Parameters.FLASH_MODE_OFF);
params.setPictureFormat(ImageFormat.JPEG);
mCamera.setParameters(params);
mCamera.startPreview();
mCamera.takePicture(null, null, null, new PictureCallback() {
    @Override
    public void onPictureTaken(byte[] data, Camera camera) {
        Log.i(Version.APP_ID, "picture-taken");
    }
});