要开发一个相机软件，你需要遵循以下步骤：
权限设置
在AndroidManifest.xml中添加使用相机硬件的权限：
```xml
```
检测相机硬件
在运行时检查设备是否具有相机硬件，可以使用`PackageManager.hasSystemFeature（）`方法：
```java
private boolean checkCameraHardware(Context context) {
return context.getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA);
}
```
创建相机预览
创建一个继承自`SurfaceView`的类，并实现`SurfaceHolder.Callback`接口，用于显示相机预览：
```java
public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {
private Camera camera;
public CameraPreview(Context context) {
super(context);
getHolder().addCallback(this);
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
try {
camera = Camera.open();
camera.setPreviewDisplay(holder);
} catch (IOException e) {
e.printStackTrace();
}
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
if (holder.getSurface() == null || camera == null) {
return;
}
try {
camera.stopPreview();
camera.setPreviewDisplay(holder);
camera.startPreview();
} catch (IOException e) {
e.printStackTrace();
}
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
if (camera != null) {
camera.stopPreview();
camera.release();
camera = null;
}
}
}
```
拍照功能
创建一个用于拍照的监听器，并在拍照时存储图片到文件系统：
```java
private Camera.PictureCallback mPictureCallback = new Camera.PictureCallback() {
@Override
public void onPictureTaken(byte[] data, Camera camera) {
// 处理拍照后的图片数据，例如保存到文件
}
};
private void takePicture() {
Camera.CameraInfo info = new Camera.CameraInfo();
Camera.getCameraInfo(cameraIndex, info);
int deviceOrientation = info.orientation;
Matrix matrix = new Matrix();
matrix.postRotate(deviceOrientation);
// 创建一个ImageReader用于获取拍照后的图片数据
ImageReader imageReader = ImageReader.newInstance(previewSize.width, previewSize.height, ImageFormat.JPEG, 2);
imageReader.setOnImageAvailableListener(new ImageReader.OnImageAvailableListener() {
@Override
public void onImageAvailable(ImageReader reader) {
try {
Image image = reader.acquireLatestImage();
// 处理图片数据
} catch (IOException e) {
e.printStackTrace();
}
}
}, null);
// 创建一个CaptureRequest用于拍照
CaptureRequest.Builder captureBuilder = camera.createCaptureRequest(CameraDevice.TEMPLATE_STILL_CAPTURE);
captureBuilder.addTarget(imageReader.getSurface());
// 设置拍照参数
captureBuilder.set(CaptureRequest.CONTROL_AF_MODE, CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE);
captureBuilder.set(CaptureRequest.JPEG_ORIENTATION, getOrientation(rotation));
// 拍照
camera.setPreviewRequest(captureBuilder.build());
camera.takePicture(captureBuilder.build(), null, mPictureCallback);
}
```
释放相机资源
在不再需要相机时，确保释放相机资源：
```java
@Override
protected void onPause() {
super.onPause();
if (camera != null) {
camera.stopPreview();
camera.release();
camera = null;
}
}
```
以上步骤提供了一个基本的相机软件框架，你可以根据具体需求进行扩展和优化。建议参考Android官方文档和相关的开源库，以获取更详细的信息和示例代码。
