最近项目中使用相机功能，需要自定义，整理下，给需要的朋友
实现的功能：前后镜头切换、闪光灯模式(三种)、对焦、镜头手势缩放、本地保存、弹窗预览
实现逻辑：自定义View继承自SurfaceView，Activity 布局中引入，在Activity中进行各种操作 拍照，对焦等等
镜头切换方法：
//切换摄像头
private int cameraPosition = 1; //当前选用的摄像头，1后置 0前置
public void switchFrontCamera() {
int cameraCount = Camera.getNumberOfCameras();//得到摄像头的个数
Camera.CameraInfo cameraInfo = new Camera.CameraInfo();
for (int i = 0; i < cameraCount; i++) {
Camera.getCameraInfo(i, cameraInfo);//得到每一个摄像头的信息
if (cameraPosition == 1) {
//现在是后置，变更为前置
if (cameraInfo.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) {//代表摄像头的方位，CAMERA_FACING_FRONT前置 CAMERA_FACING_BACK后置
//重新打开
reStartCamera(i);
cameraPosition = 0;
break;
}
} else {
//现在是前置， 变更为后置
if (cameraInfo.facing == Camera.CameraInfo.CAMERA_FACING_BACK) {//代表摄像头的方位，CAMERA_FACING_FRONT前置 CAMERA_FACING_BACK后置
reStartCamera(i);
cameraPosition = 1;
break;
}
}
}
}
//重新打开预览
public void reStartCamera(int i) {
if (camera != null) {
camera.stopPreview();//停掉原来摄像头的预览
camera.release();//释放资源
camera = null;//取消原来摄像头
}
try {
camera = Camera.open(i);//打开当前选中的摄像头
camera.setPreviewDisplay(holder);//通过surfaceview显示取景画面
// camera.setDisplayOrientation(90);// 屏幕方向
camera.startPreview();//开始预览
} catch (IOException e) {
e.printStackTrace();
}
}
闪光灯模式
camePreview.setIsOpenFlashMode(Camera.Parameters.FLASH_MODE_AUTO);//自动模式
camePreview.setIsOpenFlashMode(Camera.Parameters.FLASH_MODE_ON);//总是开启
camePreview.setIsOpenFlashMode(Camera.Parameters.FLASH_MODE_OFF);//总是关闭
//设置开启闪光灯(重新预览)
public void setIsOpenFlashMode(String mIsOpenFlashMode) {
Camera.Parameters mParameters = camera.getParameters();
//设置闪光灯模式
mParameters.setFlashMode(mIsOpenFlashMode);
camera.setParameters(mParameters);
}
镜头对焦
// 手动对焦
public void autoFocus() {
camera.autoFocus(null);//自动对焦 不需要回调
}
//自动连续对焦
Camera.Parameters parameters = camera.getParameters();
if (parameters.getSupportedFocusModes().contains(android.hardware.Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE)) {
parameters.setFocusMode(android.hardware.Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE);// 连续对焦模式
}
camera.setParameters(parameters);
手势缩放
//Activity中初始化
ScaleGestureDetector gestureDetector = new ScaleGestureDetector(this, new ScaleGestureListener());
//重写onTouchEvent方法 获取手势
@Override
public boolean onTouchEvent(MotionEvent event) {
//识别手势
gestureDetector.onTouchEvent(event);
return super.onTouchEvent(event);
}
//操作类
class ScaleGestureListener implements ScaleGestureDetector.OnScaleGestureListener {
float mScaleFactor;
@Override
public boolean onScale(ScaleGestureDetector detector) {
if (detector.getCurrentSpan() > mScaleFactor) {
camePreview.zoomOut();
} else {
camePreview.zoomIn();
}
mScaleFactor = detector.getCurrentSpan();
return false;
}
@Override
public boolean onScaleBegin(ScaleGestureDetector detector) {
mScaleFactor = detector.getCurrentSpan();
//一定要返回true才会进入onScale()这个函数
return true;
}
@Override
public void onScaleEnd(ScaleGestureDetector detector) {
mScaleFactor = detector.getCurrentSpan();
}
}
//自定义相机View中定义方法
//放大
public void zoomOut() {
Camera.Parameters parameters = camera.getParameters();
if (!parameters.isZoomSupported()) return;
int zoom = parameters.getZoom() + 1;
if (zoom < parameters.getMaxZoom()) {
parameters.setZoom(zoom);
camera.setParameters(parameters);
}
}
//缩小
public void zoomIn() {
Camera.Parameters parameters = camera.getParameters();
if (!parameters.isZoomSupported()) return;
int zoom = parameters.getZoom() - 1;
if (zoom >= 0) {
parameters.setZoom(zoom);
camera.setParameters(parameters);
}
}
预览使用Dialog，还有前后摄像头拍照方向问题
//bitmap旋转90度
Matrix matrix = new Matrix();
matrix.setRotate(90);
Bitmap waterMarkBitmap = Bitmap.createBitmap(waterMarkBitmap, 0, 0, waterMarkBitmap.getWidth(), waterMarkBitmap.getHeight(), matrix, true);
