Android之调用本地摄像头

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

http://www.cnblogs.com/over140/archive/2011/11/16/2251344.html

1、布局

1<SurfaceView 
2     android:layout_width="fill_parent"
3     android:layout_height="fill_parent"
4     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：

1@Override
2	public void surfaceChanged(SurfaceHolder arg0, int arg1, int arg2, int arg3) {
3		System.out.println("surfacechanged");
4	}
5
6@Override
7	public void surfaceCreated(SurfaceHolder holder) {
8		System.out.println("surfacecreated");
9		//获取camera对象
10		camera = Camera.open();
11		try {
12			//设置预览监听
13			camera.setPreviewDisplay(holder);
14			Camera.Parameters parameters = camera.getParameters();
15			
16			if (this.getResources().getConfiguration().orientation 
17						!= Configuration.ORIENTATION_LANDSCAPE) {
18				parameters.set("orientation", "portrait");
19				camera.setDisplayOrientation(90);
20				parameters.setRotation(90);
21			} else {
22				parameters.set("orientation", "landscape");
23				camera.setDisplayOrientation(0);
24				parameters.setRotation(0);
25			}
26			camera.setParameters(parameters);
27			//启动摄像头预览
28			camera.startPreview();
29			System.out.println("camera.startpreview");
30			
31		} catch (IOException e) {
32			e.printStackTrace();
33			camera.release();
34			System.out.println("camera.release");
35		}
36	}
37
38@Override
39	public void surfaceDestroyed(SurfaceHolder arg0) {
40		System.out.println("surfaceDestroyed");
41		if (camera != null) {
42			camera.stopPreview();
43			camera.release();			
44		}
45	}

当然还有onCreate方法

1@Override
2	protected void onCreate(Bundle savedInstanceState) {
3		super.onCreate(savedInstanceState);
4		setContentView(R.layout.activity_main);
5		context = this;
6		
7		surfaceview = (SurfaceView)findViewById(R.id.surfaceview);
8		surfaceholder = surfaceview.getHolder();
9		surfaceholder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
10		surfaceholder.addCallback(SafeActivity.this);
11	}

,

当然有些变量还需要定义，

1private static Context context = null;
2	private SurfaceView surfaceview;
3	private SurfaceHolder surfaceholder;
4	private Camera camera = null;