Android自定义照相机倒计时拍照

核心代码详解：

1.创建SurfaceView时，surfaceCreated()方法中

for (int i = 0; i < Camera.getNumberOfCameras(); i++) {
  CameraInfo info = new CameraInfo();
  Camera.getCameraInfo(i, info);
  // 调用系统的前置摄像头
  if (info.facing == CameraInfo.CAMERA_FACING_FRONT) {
  camera = Camera.open(i);
  }
 }

此部分代码为打开相机时默认打开前置摄像头CameraInfo.CAMERA_FACING_BACK为默认打开后置摄像头，CameraInfo.CAMERA_FACING_FRONT前置摄像头

2.照片拍摄takePhoto()方法中：

Bitmap bitmap = BitmapFactory.decodeByteArray(data, 0,
  data.length);
  timeString = formatDate();
  filename = "/data/data/com.example.pujiejiaapp/images/"
  + timeString + ".jpg";
  photo = timeString + ".jpg";
  File file = new File(filename);
  boolean createNewFile = file.createNewFile();
  FileOutputStream outStream = new FileOutputStream(file);
  bitmap.compress(Bitmap.CompressFormat.JPEG, 60, outStream);

此部分代码为将拍摄到的图片保存为以bitmap格式保存在指定的目录下

3.开子线程用于倒计时拍摄

public void run() {
 while (!stopThread) {
 try {
 Thread.sleep(1000);
 } catch (InterruptedException e) {
 // TODO Auto-generated catch block
 e.printStackTrace();
 }
 cameratime--;
 mHandler.sendEmptyMessage(222);
 if (cameratime <= 0) {
 break;
 }
 }
 }

希望大家理解核心代码的详细注释，欢迎提供意见，希望能给大家带来帮助，谢谢！

注：相关教程知识阅读请移步到Android开发频道。