代码与范例：
首先需要在Manifest文件中添加以下内容：
以使程序获取摄像头使用以及自动对焦功能的使用权限。
CameraTestActivity.java
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 |
import android.app.Activity; import android.os.Bundle; import android.view.Window; import android.view.WindowManager; public class CameraTestActivity extends Activity { @Override public void onCreate(Bundle bundle) { super.onCreate(bundle); getWindow().clearFlags(WindowManager.LayoutParams.FLAG_FORCE_NOT_FULLSCREEN); getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN); requestWindowFeature(Window.FEATURE_NO_TITLE);// 设置横屏模式以及全屏模式 setContentView(new CameraView(this)); //设置View } } |
CameraView.java
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 |
import java.io.FileOutputStream; import android.content.Context; import android.hardware.Camera; import android.os.Environment; import android.view.MotionEvent; import android.view.SurfaceHolder; import android.view.SurfaceView; public class CameraView extends SurfaceView implements SurfaceHolder.Callback, Camera.PictureCallback { private SurfaceHolder holder; private Camera camera; private boolean af; public CameraView(Context context) {//构造函数 super(context); holder = getHolder();//生成Surface Holder holder.addCallback(this); holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);//指定Push Buffer } public void surfaceCreated(SurfaceHolder holder) {//Surface生成事件的处理 try { camera = Camera.open();//摄像头的初始化 camera.setPreviewDisplay(holder); } catch (Exception e) { } } @Override public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {//Surface改变事件的处理 Camera.Parameters parameters = camera.getParameters(); parameters.setPreviewSize(width, height); camera.setParameters(parameters);//设置参数 camera.startPreview();//开始预览 } public void surfaceDestroyed(SurfaceHolder holder) {//Surface销毁时的处理 camera.setPreviewCallback(null); camera.stopPreview(); camera.release(); camera = null; } @Override public boolean onTouchEvent(MotionEvent event) {//屏幕触摸事件 if (event.getAction() == MotionEvent.ACTION_DOWN) {//按下时自动对焦 camera.autoFocus(null); af = true; } if (event.getAction() == MotionEvent.ACTION_UP && af == true) {//放开后拍照 camera.takePicture(null, null, this); af = false; } return true; } public void onPictureTaken(byte[] data, Camera camera) {//拍摄完成后保存照片 try { String path = Environment.getExternalStorageDirectory() + "/test.jpg"; data2file(data, path); } catch (Exception e) { } camera.startPreview(); } private void data2file(byte[] w, String fileName) throws Exception {//将二进制数据转换为文件的函数 FileOutputStream out = null; try { out = new FileOutputStream(fileName); out.write(w); out.close(); } catch (Exception e) { if (out != null) out.close(); throw e; } } } |
说明：这是一个简单的示例程序。功能是使用自动对焦功能拍摄一张照片保存于SD卡根目录下。需要注意的是要在manifest文件中声明相关的许可。本例中许多参数都没有设置，可以根据具体需要进行适当的修改以满足特定要求。