安卓调用相机和自定义相机SurfaceView实现预览

private File file;
public void startCamera(View view) {
Intent intent = new Intent();
intent.setAction(MediaStore.ACTION_IMAGE_CAPTURE);
file = new File("/mnt/sdcard/my.jpg");
intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(file));
startActivityForResult(intent, 1);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode==1) {
Bitmap bitmap = BitmapFactory.decodeFile("/mnt/sdcard/my.jpg");
iv.setImageBitmap(bitmap);
}
}

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

<SurfaceView
android:id="@+id/sv"
android:layout_width="match_parent"
android:layout_height="match_parent" />

SurfaceView sv = (SurfaceView) findViewById(R.id.sv);
holder = sv.getHolder();
holder.addCallback(new Callback() {
//当界面不可见的时候回调该方法
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
if (camera!=null) {
//停止预览
camera.stopPreview();
//释放资源
camera.release();
camera = null;
}
}
//当 界面展现出来的时候回调
@Override
public void surfaceCreated(SurfaceHolder holder) {
if (camera==null) {
//打开照相机
camera = Camera.open();
}
//开启预览
camera.startPreview();
try {
//设置预览界面
camera.setPreviewDisplay(holder);
} catch (IOException e) {
e.printStackTrace();
}
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {

}
});

if (camera!=null) {
//参数1：拍照声音的回调
//参数2：照片的原生的没有压缩过的数据
//参数3：压缩过后的相片数据
camera.takePicture(null, null, new PictureCallback() {
//参数1：照片的字节码
@Override
public void onPictureTaken(byte[] data, Camera camera) {
try {
//将data保存到sdcard上
FileOutputStream fos = new FileOutputStream(new File("/mnt/sdcard/my2.jpg"));
fos.write(data);
fos.close();
/*
* 需要重新开启预览，因此拍照的时候，系统会自动停止预览
*/
camera.startPreview();
} catch (Exception e) {
e.printStackTrace();
}
}
});
}

//点击拍照按钮，摄像头自动对焦，对焦完成后拍照并保存
camera.autoFocus(new AutoFocusCallback() {
@Override
public void onAutoFocus(boolean success, Camera camera) {
//对焦完成，拍照并保存
camera.takePicture(null, null, new PictureCallback() {
@Override
public void onPictureTaken(byte[] data, Camera camera) {
//设置照片保存路径
String path =Environment.getExternalStorageDirectory().getAbsolutePath() + "/" +UUID.randomUUID().toString() + ".jpg";
try {
FileOutputStream outputStream = new FileOutputStream(path);
//将照片字节数组写到文件中
outputStream.write(data);
outputStream.close();
//重新开启预览
camera.startPreview();
} catch (Exception e) {
e.printStackTrace();
}
}
});
}