做应用可能有时候需要调用本地的摄像头，所以这里就记录意下如何调用。

摄像头预览需要在布局文件添加surfaceview, 这里需要注意，其实用FrameLayout也可以，大家可以参考

1、布局

android:layout_width="fill_parent"

android:layout_height="fill_parent"

android:id="@+id/surfaceview"/>

只要在布局文件添加这个即可。

2、摄像头预览

public class MainActivity extends Activity implements SurfaceHolder.Callback

继承Activity，实现SurfaceHolder.Callback，MainActivity里需要我们复写以下几个方法：

@Override

public void surfaceChanged(SurfaceHolder arg0, int arg1, int arg2, int arg3) {

System.out.println("surfacechanged");

}

@Override

public void surfaceCreated(SurfaceHolder holder) {

System.out.println("surfacecreated");

//获取camera对象

camera = Camera.open();

try {

//设置预览监听

camera.setPreviewDisplay(holder);

Camera.Parameters parameters = camera.getParameters();

if (this.getResources().getConfiguration().orientation

!= Configuration.ORIENTATION_LANDSCAPE) {

parameters.set("orientation", "portrait");

camera.setDisplayOrientation(90);

parameters.setRotation(90);

} else {

parameters.set("orientation", "landscape");

camera.setDisplayOrientation(0);

parameters.setRotation(0);

}

camera.setParameters(parameters);

//启动摄像头预览

camera.startPreview();

System.out.println("camera.startpreview");

} catch (IOException e) {

e.printStackTrace();

camera.release();

System.out.println("camera.release");

}

}

@Override

public void surfaceDestroyed(SurfaceHolder arg0) {

System.out.println("surfaceDestroyed");

if (camera != null) {

camera.stopPreview();

camera.release();

}

}

当然还有onCreate方法

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

context = this;

surfaceview = (SurfaceView)findViewById(R.id.surfaceview);

surfaceholder = surfaceview.getHolder();

surfaceholder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);

surfaceholder.addCallback(SafeActivity.this);

}

,

当然有些变量还需要定义，

private static Context context = null;

private SurfaceView surfaceview;

private SurfaceHolder surfaceholder;

private Camera camera = null;