Android调用前后摄像头同时工作实例代码

硬件环境：小米4

Android版本：6.0

咱们先看效果图：

我把代码贴出来：

AndroidMainfest.xml文件（需要新增camera权限）：

 <uses-permission android:name="android.permission.CAMERA" />

activity_main.xml文件：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context="com.bihu.qdemopush.MainActivity">

<LinearLayout
 android:layout_width="match_parent"
 android:layout_height="200dp"
 android:orientation="horizontal">
 <SurfaceView
   android:id="@+id/surfaceview1"
   android:layout_width="0dp"
   android:layout_weight="1"
   android:layout_height="fill_parent" />
 <SurfaceView
   android:id="@+id/surfaceview2"
   android:layout_width="0dp"
   android:layout_weight="1"
   android:layout_marginLeft="5dp"
   android:layout_height="fill_parent" />
</LinearLayout>
</LinearLayout>

MainActivity.java文件：主要是对2个surfaceView的显示渲染

public class MainActivity extends AppCompatActivity {

SurfaceView surfaceview1, surfaceview2;
SurfaceHolder surfaceholder1, surfaceholder2;
String TAG = "MainActivity";
private Camera camera1 = null, camera2;
Camera.Parameters parameters;

@Override
protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.activity_main);

surfaceview1 = (SurfaceView) findViewById(R.id.surfaceview1);
 surfaceview2 = (SurfaceView) findViewById(R.id.surfaceview2);
 surfaceholder1 = surfaceview1.getHolder();
 surfaceholder1.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
 surfaceholder1.addCallback(new surfaceholderCallbackBack());

surfaceholder2 = surfaceview2.getHolder();
 surfaceholder2.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
 surfaceholder2.addCallback(new surfaceholderCallbackFont());
}

@Override
protected void onDestroy() {
 Log.e(TAG, "onDestroy");
 super.onDestroy();
}

/**
* 后置摄像头回调
*/
class surfaceholderCallbackBack implements SurfaceHolder.Callback {
 @Override
 public void surfaceCreated(SurfaceHolder holder) {
   // 获取camera对象
   int cameraCount = Camera.getNumberOfCameras();
   if (cameraCount > 0) {
     camera1 = Camera.open(0);
     try {
       // 设置预览监听
       camera1.setPreviewDisplay(holder);
       Camera.Parameters parameters = camera1.getParameters();

if (MainActivity.this.getResources().getConfiguration().orientation != Configuration.ORIENTATION_LANDSCAPE) {
         parameters.set("orientation", "portrait");
         camera1.setDisplayOrientation(90);
         parameters.setRotation(90);
       } else {
         parameters.set("orientation", "landscape");
         camera1.setDisplayOrientation(0);
         parameters.setRotation(0);
       }
       camera1.setParameters(parameters);
       // 启动摄像头预览
       camera1.startPreview();
       System.out.println("camera.startpreview");

} catch (IOException e) {
       e.printStackTrace();
       camera1.release();
       System.out.println("camera.release");
     }
   }
 }

@Override
 public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
   camera1.autoFocus(new Camera.AutoFocusCallback() {
     @Override
     public void onAutoFocus(boolean success, Camera camera) {
       if (success) {
         initCamera();// 实现相机的参数初始化
         camera.cancelAutoFocus();// 只有加上了这一句，才会自动对焦。
       }
     }
   });

}

@Override
 public void surfaceDestroyed(SurfaceHolder holder) {

}

// 相机参数的初始化设置
 private void initCamera() {
   parameters = camera1.getParameters();
   parameters.setPictureFormat(PixelFormat.JPEG);
   parameters.setFocusMode(Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE);// 1连续对焦
   setDispaly(parameters, camera1);
   camera1.setParameters(parameters);
   camera1.startPreview();
   camera1.cancelAutoFocus();// 2如果要实现连续的自动对焦，这一句必须加上
 }

// 控制图像的正确显示方向
 private void setDispaly(Camera.Parameters parameters, Camera camera) {
   if (Integer.parseInt(Build.VERSION.SDK) >= 8) {
     setDisplayOrientation(camera, 90);
   } else {
     parameters.setRotation(90);
   }

}

// 实现的图像的正确显示
 private void setDisplayOrientation(Camera camera, int i) {
   Method downPolymorphic;
   try {
     downPolymorphic = camera.getClass().getMethod("setDisplayOrientation", new Class[]{int.class});
     if (downPolymorphic != null) {
       downPolymorphic.invoke(camera, new Object[]{i});
     }
   } catch (Exception e) {
     Log.e("Came_e", "图像出错");
   }
 }
}

class surfaceholderCallbackFont implements SurfaceHolder.Callback {
 @Override
 public void surfaceCreated(SurfaceHolder holder) {
   // 获取camera对象
   int cameraCount = Camera.getNumberOfCameras();
   if (cameraCount == 2) {
     camera2 = Camera.open(1);
   }
   try {
     // 设置预览监听
     camera2.setPreviewDisplay(holder);
     Camera.Parameters parameters = camera2.getParameters();

if (MainActivity.this.getResources().getConfiguration().orientation != Configuration.ORIENTATION_LANDSCAPE) {
       parameters.set("orientation", "portrait");
       camera2.setDisplayOrientation(90);
       parameters.setRotation(90);
     } else {
       parameters.set("orientation", "landscape");
       camera2.setDisplayOrientation(0);
       parameters.setRotation(0);
     }
     camera2.setParameters(parameters);
     // 启动摄像头预览
     camera2.startPreview();
     System.out.println("camera.startpreview");

} catch (IOException e) {
     e.printStackTrace();
     camera2.release();
     System.out.println("camera.release");
   }
 }

@Override
 public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
   camera2.autoFocus(new Camera.AutoFocusCallback() {
     @Override
     public void onAutoFocus(boolean success, Camera camera) {
       if (success) {
         parameters = camera2.getParameters();
         parameters.setPictureFormat(PixelFormat.JPEG);
         parameters.setFocusMode(Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE);// 1连续对焦
         setDispaly(parameters, camera2);
         camera2.setParameters(parameters);
         camera2.startPreview();
         camera2.cancelAutoFocus();// 2如果要实现连续的自动对焦，这一句必须加上
         camera.cancelAutoFocus();// 只有加上了这一句，才会自动对焦。
       }
     }
   });

}

@Override
 public void surfaceDestroyed(SurfaceHolder holder) {

}

// 控制图像的正确显示方向
 private void setDispaly(Camera.Parameters parameters, Camera camera) {
   if (Integer.parseInt(Build.VERSION.SDK) >= 8) {
     setDisplayOrientation(camera, 90);
   } else {
     parameters.setRotation(90);
   }

}

// 实现的图像的正确显示
 private void setDisplayOrientation(Camera camera, int i) {
   Method downPolymorphic;
   try {
     downPolymorphic = camera.getClass().getMethod("setDisplayOrientation", new Class[]{int.class});
     if (downPolymorphic != null) {
       downPolymorphic.invoke(camera, new Object[]{i});
     }
   } catch (Exception e) {
     Log.e("Came_e", "图像出错");
   }
 }
}
}

可能出现的问题：

1、没有权限，需要手动打开，代码里由于追求简便，没有主动申请，只在mainfest中注册了

来源：http://www.jianshu.com/p/8f62ce31794c