Android 安卓相机片段预览
到目前为止，我有一个完整的工作代码，可以插入一个摄像头来查看前摄像头的预览 我现在要做的是让相机在Android 安卓相机片段预览,android,android-fragments,android-camera,Android,Android Fragments,Android Camera,到目前为止，我有一个完整的工作代码，可以插入一个摄像头来查看前摄像头的预览 我现在要做的是让相机在片段中工作 完整代码： MainActivity.java public class MainActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.
片段中工作
完整代码：
MainActivity.java
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.fragment_main);
getFragmentManager().beginTransaction().add(R.id.mainLayout, new CameraExtractionFragment()).commit();
}
}
public class CameraExtractionFragment extends Fragment {
private CameraExtraction mCameraExtraction;
Camera mCamera;
int mNumberOfCameras;
int cameraId;
int rotation;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mCameraExtraction = new CameraExtraction(
this.getActivity().getBaseContext(),
this.getActivity().getWindowManager().getDefaultDisplay().getRotation()
);
// Find the total number of cameras available
mNumberOfCameras = Camera.getNumberOfCameras();
// Find the ID of the rear-facing ("default") camera
CameraInfo cameraInfo = new CameraInfo();
for (int i = 0; i < mNumberOfCameras; i++) {
Camera.getCameraInfo(i, cameraInfo);
if (cameraInfo.facing == CameraInfo.CAMERA_FACING_FRONT) {
cameraId = i;
}
}
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
return mCameraExtraction;
}
@Override
public void onResume() {
super.onResume();
// Use mCurrentCamera to select the camera desired to safely restore
// the fragment after the camera has been changed
mCamera = Camera.open(cameraId);
mCameraExtraction.setCamera(mCamera);
}
@Override
public void onPause() {
super.onPause();
if (mCamera != null)
{
mCamera.release();
}
}
// Modo en el que se pinta la cámara: encajada por dentro o saliendo los bordes por fuera.
public enum CameraViewMode {
/**
* Inner mode
*/
Inner,
/**
* Outer mode
*/
Outer
}
}
public class CameraExtraction extends ViewGroup implements SurfaceHolder.Callback {
private final String TAG = "CameraExtraction";
Camera mCamera;
SurfaceHolder mHolder;
SurfaceView mSurfaceView;
int mNumberOfCameras;
int cameraId;
Rect desiredSize;
CameraViewMode cameraViewMode;
boolean mSurfaceCreated = false;
List<Size> mSupportedPreviewSizes;
int rotation;
Size mPreviewSize;
public CameraExtraction(Context context, int rotation) {
super(context);
this.rotation = rotation;
mSurfaceView = new SurfaceView(context);
addView(mSurfaceView);
// Install a SurfaceHolder.Callback so we get notified when the
mHolder = mSurfaceView.getHolder();
mHolder.addCallback(this);
mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
cameraViewMode = CameraViewMode.Inner;
}
public void setCamera(Camera camera) {
mCamera = camera;
if (mCamera != null) {
mSupportedPreviewSizes = mCamera.getParameters().getSupportedPreviewSizes();
if (mSurfaceCreated) requestLayout();
}
}
public void switchCamera(Camera camera) {
setCamera(camera);
try {
camera.setPreviewDisplay(mHolder);
} catch (IOException exception) {
Log.e(TAG, "IOException caused by setPreviewDisplay()", exception);
}
}
@SuppressLint("DrawAllocation")
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
if (mSurfaceView == null ||mSurfaceView.getHolder() == null) return;
if (mSurfaceView.getHolder().getSurface() == null) {
// preview surface does not exist
return;
}
final int width = resolveSize(getSuggestedMinimumWidth(),
widthMeasureSpec);
final int height = resolveSize(getSuggestedMinimumHeight(),
heightMeasureSpec);
setMeasuredDimension(width, height);
if (mSupportedPreviewSizes != null) {
mPreviewSize = getNearestPreviewSize(mCamera.new Size(widthMeasureSpec,heightMeasureSpec));
}
if (mCamera != null) {
Camera.Parameters parameters = mCamera.getParameters();
parameters.setPreviewSize(mPreviewSize.width, mPreviewSize.height);
mCamera.setParameters(parameters);
}
}
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
if (getChildCount() > 0) {
final View child = getChildAt(0);
final int width = r - l;
final int height = b - t;
int previewWidth = width;
int previewHeight = height;
if (mPreviewSize != null) {
previewWidth = mPreviewSize.width;
previewHeight = mPreviewSize.height;
}
// Center the child SurfaceView within the parent.
if (width * previewHeight > height * previewWidth) {
final int scaledChildWidth = previewWidth * height
/ previewHeight;
child.layout((width - scaledChildWidth) / 2, 0,
(width + scaledChildWidth) / 2, height);
} else {
final int scaledChildHeight = previewHeight * width
/ previewWidth;
child.layout(0, (height - scaledChildHeight) / 2, width,
(height + scaledChildHeight) / 2);
}
}
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
mCamera = Camera.open(cameraId);
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width,int height) {
if (mSurfaceView == null || mSurfaceView.getHolder() == null) return;
if (mSurfaceView.getHolder().getSurface() == null) {
// preview surface does not exist
return;
}
// set preview size and make any resize, rotate or
// reformatting changes here
Camera.Parameters param = mCamera.getParameters();
Point previewSize = new Point(640,480);
Camera.Size size = getNearestPreviewSize(mCamera.new Size(previewSize.x,previewSize.y));
param.setPreviewSize(size.width, size.height);
mCamera.setParameters(param);
rotation = setCameraDisplayOrientation(cameraId, mCamera);
// start preview with new settings
try {
mCamera.setPreviewCallback(new Camera.PreviewCallback() {
@Override
public void onPreviewFrame(byte[] data, Camera camera) {
// TODO Auto-generated method stub
}
});
mCamera.setPreviewDisplay(mSurfaceView.getHolder());
mCamera.startPreview();
} catch (Exception e) {
Log.d("AndroidControlSurfaceView",
"Error starting camera preview: " + e.getMessage());
}
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
if (mCamera != null)
{
mCamera.stopPreview();
mCamera.release();
}
}
protected Rect getCameraViewSizeCompensated(Camera.Size cameraPreviewSize, Point hostViewSize) {
Rect toReturn=null;
float ratioWidth = hostViewSize.x / (float)cameraPreviewSize.width;
float ratioHeight = hostViewSize.y / (float)cameraPreviewSize.height;
switch (cameraViewMode){
case Inner:
if (ratioWidth < ratioHeight) {
int newHeight = (int)(cameraPreviewSize.height*ratioWidth);
int y = (hostViewSize.y - newHeight) / 2;
toReturn = new Rect(0, y, hostViewSize.x, y+newHeight);
} else {
int newWidth = (int)(cameraPreviewSize.width*ratioHeight);
int x = (hostViewSize.x - newWidth) / 2;
toReturn = new Rect(x, 0, x+newWidth,hostViewSize.y);
}
break;
case Outer:
if (ratioWidth < ratioHeight) {
int newWidth = (int)(cameraPreviewSize.width*ratioHeight);
int x = (hostViewSize.x - newWidth) / 2;
toReturn = new Rect(x, 0, x+newWidth,hostViewSize.y);
} else {
int newHeight = (int)(cameraPreviewSize.height*ratioWidth);
int y = (hostViewSize.y - newHeight) / 2;
toReturn = new Rect(0, y, hostViewSize.x, y+newHeight);
}
break;
}
return toReturn;
}
private Camera.Size getNearestPreviewSize(Camera.Size size) {
List<Camera.Size> availableSizes = mCamera.getParameters().getSupportedPreviewSizes();
if (availableSizes == null || availableSizes.size() <= 0) return null;
Camera.Size toReturn = availableSizes.get(0);
int distance = Math.abs(size.width*size.height - toReturn.width*toReturn.height);
for (int a=1; a<availableSizes.size(); a++) {
int temp = Math.abs(size.width*size.height - availableSizes.get(a).width*availableSizes.get(a).height);
if (temp < distance) {
distance = temp;
toReturn = availableSizes.get(a);
}
}
return toReturn;
}
public int setCameraDisplayOrientation(int cameraId, android.hardware.Camera camera) {
CameraInfo info = new Camera.CameraInfo();
Camera.getCameraInfo(cameraId, info);
int degrees = 0;
switch (rotation) {
case Surface.ROTATION_0: degrees = 0; break;
case Surface.ROTATION_90: degrees = 90; break;
case Surface.ROTATION_180: degrees = 180; break;
case Surface.ROTATION_270: degrees = 270; break;
}
int result;
if (info.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) {
result = (info.orientation + degrees) % 360;
result = (360 - result) % 360; // compensate the mirror
} else { // back-facing
result = (info.orientation - degrees + 360) % 360;
}
camera.setDisplayOrientation(result);
return result/90;
}
}
CameraExtractionFragment.java
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.fragment_main);
getFragmentManager().beginTransaction().add(R.id.mainLayout, new CameraExtractionFragment()).commit();
}
}
public class CameraExtractionFragment extends Fragment {
private CameraExtraction mCameraExtraction;
Camera mCamera;
int mNumberOfCameras;
int cameraId;
int rotation;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mCameraExtraction = new CameraExtraction(
this.getActivity().getBaseContext(),
this.getActivity().getWindowManager().getDefaultDisplay().getRotation()
);
// Find the total number of cameras available
mNumberOfCameras = Camera.getNumberOfCameras();
// Find the ID of the rear-facing ("default") camera
CameraInfo cameraInfo = new CameraInfo();
for (int i = 0; i < mNumberOfCameras; i++) {
Camera.getCameraInfo(i, cameraInfo);
if (cameraInfo.facing == CameraInfo.CAMERA_FACING_FRONT) {
cameraId = i;
}
}
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
return mCameraExtraction;
}
@Override
public void onResume() {
super.onResume();
// Use mCurrentCamera to select the camera desired to safely restore
// the fragment after the camera has been changed
mCamera = Camera.open(cameraId);
mCameraExtraction.setCamera(mCamera);
}
@Override
public void onPause() {
super.onPause();
if (mCamera != null)
{
mCamera.release();
}
}
// Modo en el que se pinta la cámara: encajada por dentro o saliendo los bordes por fuera.
public enum CameraViewMode {
/**
* Inner mode
*/
Inner,
/**
* Outer mode
*/
Outer
}
}
public class CameraExtraction extends ViewGroup implements SurfaceHolder.Callback {
private final String TAG = "CameraExtraction";
Camera mCamera;
SurfaceHolder mHolder;
SurfaceView mSurfaceView;
int mNumberOfCameras;
int cameraId;
Rect desiredSize;
CameraViewMode cameraViewMode;
boolean mSurfaceCreated = false;
List<Size> mSupportedPreviewSizes;
int rotation;
Size mPreviewSize;
public CameraExtraction(Context context, int rotation) {
super(context);
this.rotation = rotation;
mSurfaceView = new SurfaceView(context);
addView(mSurfaceView);
// Install a SurfaceHolder.Callback so we get notified when the
mHolder = mSurfaceView.getHolder();
mHolder.addCallback(this);
mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
cameraViewMode = CameraViewMode.Inner;
}
public void setCamera(Camera camera) {
mCamera = camera;
if (mCamera != null) {
mSupportedPreviewSizes = mCamera.getParameters().getSupportedPreviewSizes();
if (mSurfaceCreated) requestLayout();
}
}
public void switchCamera(Camera camera) {
setCamera(camera);
try {
camera.setPreviewDisplay(mHolder);
} catch (IOException exception) {
Log.e(TAG, "IOException caused by setPreviewDisplay()", exception);
}
}
@SuppressLint("DrawAllocation")
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
if (mSurfaceView == null ||mSurfaceView.getHolder() == null) return;
if (mSurfaceView.getHolder().getSurface() == null) {
// preview surface does not exist
return;
}
final int width = resolveSize(getSuggestedMinimumWidth(),
widthMeasureSpec);
final int height = resolveSize(getSuggestedMinimumHeight(),
heightMeasureSpec);
setMeasuredDimension(width, height);
if (mSupportedPreviewSizes != null) {
mPreviewSize = getNearestPreviewSize(mCamera.new Size(widthMeasureSpec,heightMeasureSpec));
}
if (mCamera != null) {
Camera.Parameters parameters = mCamera.getParameters();
parameters.setPreviewSize(mPreviewSize.width, mPreviewSize.height);
mCamera.setParameters(parameters);
}
}
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
if (getChildCount() > 0) {
final View child = getChildAt(0);
final int width = r - l;
final int height = b - t;
int previewWidth = width;
int previewHeight = height;
if (mPreviewSize != null) {
previewWidth = mPreviewSize.width;
previewHeight = mPreviewSize.height;
}
// Center the child SurfaceView within the parent.
if (width * previewHeight > height * previewWidth) {
final int scaledChildWidth = previewWidth * height
/ previewHeight;
child.layout((width - scaledChildWidth) / 2, 0,
(width + scaledChildWidth) / 2, height);
} else {
final int scaledChildHeight = previewHeight * width
/ previewWidth;
child.layout(0, (height - scaledChildHeight) / 2, width,
(height + scaledChildHeight) / 2);
}
}
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
mCamera = Camera.open(cameraId);
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width,int height) {
if (mSurfaceView == null || mSurfaceView.getHolder() == null) return;
if (mSurfaceView.getHolder().getSurface() == null) {
// preview surface does not exist
return;
}
// set preview size and make any resize, rotate or
// reformatting changes here
Camera.Parameters param = mCamera.getParameters();
Point previewSize = new Point(640,480);
Camera.Size size = getNearestPreviewSize(mCamera.new Size(previewSize.x,previewSize.y));
param.setPreviewSize(size.width, size.height);
mCamera.setParameters(param);
rotation = setCameraDisplayOrientation(cameraId, mCamera);
// start preview with new settings
try {
mCamera.setPreviewCallback(new Camera.PreviewCallback() {
@Override
public void onPreviewFrame(byte[] data, Camera camera) {
// TODO Auto-generated method stub
}
});
mCamera.setPreviewDisplay(mSurfaceView.getHolder());
mCamera.startPreview();
} catch (Exception e) {
Log.d("AndroidControlSurfaceView",
"Error starting camera preview: " + e.getMessage());
}
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
if (mCamera != null)
{
mCamera.stopPreview();
mCamera.release();
}
}
protected Rect getCameraViewSizeCompensated(Camera.Size cameraPreviewSize, Point hostViewSize) {
Rect toReturn=null;
float ratioWidth = hostViewSize.x / (float)cameraPreviewSize.width;
float ratioHeight = hostViewSize.y / (float)cameraPreviewSize.height;
switch (cameraViewMode){
case Inner:
if (ratioWidth < ratioHeight) {
int newHeight = (int)(cameraPreviewSize.height*ratioWidth);
int y = (hostViewSize.y - newHeight) / 2;
toReturn = new Rect(0, y, hostViewSize.x, y+newHeight);
} else {
int newWidth = (int)(cameraPreviewSize.width*ratioHeight);
int x = (hostViewSize.x - newWidth) / 2;
toReturn = new Rect(x, 0, x+newWidth,hostViewSize.y);
}
break;
case Outer:
if (ratioWidth < ratioHeight) {
int newWidth = (int)(cameraPreviewSize.width*ratioHeight);
int x = (hostViewSize.x - newWidth) / 2;
toReturn = new Rect(x, 0, x+newWidth,hostViewSize.y);
} else {
int newHeight = (int)(cameraPreviewSize.height*ratioWidth);
int y = (hostViewSize.y - newHeight) / 2;
toReturn = new Rect(0, y, hostViewSize.x, y+newHeight);
}
break;
}
return toReturn;
}
private Camera.Size getNearestPreviewSize(Camera.Size size) {
List<Camera.Size> availableSizes = mCamera.getParameters().getSupportedPreviewSizes();
if (availableSizes == null || availableSizes.size() <= 0) return null;
Camera.Size toReturn = availableSizes.get(0);
int distance = Math.abs(size.width*size.height - toReturn.width*toReturn.height);
for (int a=1; a<availableSizes.size(); a++) {
int temp = Math.abs(size.width*size.height - availableSizes.get(a).width*availableSizes.get(a).height);
if (temp < distance) {
distance = temp;
toReturn = availableSizes.get(a);
}
}
return toReturn;
}
public int setCameraDisplayOrientation(int cameraId, android.hardware.Camera camera) {
CameraInfo info = new Camera.CameraInfo();
Camera.getCameraInfo(cameraId, info);
int degrees = 0;
switch (rotation) {
case Surface.ROTATION_0: degrees = 0; break;
case Surface.ROTATION_90: degrees = 90; break;
case Surface.ROTATION_180: degrees = 180; break;
case Surface.ROTATION_270: degrees = 270; break;
}
int result;
if (info.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) {
result = (info.orientation + degrees) % 360;
result = (360 - result) % 360; // compensate the mirror
} else { // back-facing
result = (info.orientation - degrees + 360) % 360;
}
camera.setDisplayOrientation(result);
return result/90;
}
}
公共类CameraExtractionFragment扩展了片段{
私人摄像机提取；
麦克默拉照相机；
国际货币基金组织；
int cameraId；
整数旋转；
@凌驾
创建时的公共void（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）；
mCameraExtraction=新的CameraExtraction(
此.getActivity（）.getBaseContext（），
此.getActivity（）.getWindowManager（）.getDefaultDisplay（）.getRotation（）文件
);
//查找可用相机的总数
mNumberOfCameras=Camera.getNumberOfCameras（）；
//查找后向（“默认”）摄像头的ID
camerRainfo camerRainfo=新的camerRainfo（）；
for（int i=0；i
CameraExtraction.java
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.fragment_main);
getFragmentManager().beginTransaction().add(R.id.mainLayout, new CameraExtractionFragment()).commit();
}
}
public class CameraExtractionFragment extends Fragment {
private CameraExtraction mCameraExtraction;
Camera mCamera;
int mNumberOfCameras;
int cameraId;
int rotation;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mCameraExtraction = new CameraExtraction(
this.getActivity().getBaseContext(),
this.getActivity().getWindowManager().getDefaultDisplay().getRotation()
);
// Find the total number of cameras available
mNumberOfCameras = Camera.getNumberOfCameras();
// Find the ID of the rear-facing ("default") camera
CameraInfo cameraInfo = new CameraInfo();
for (int i = 0; i < mNumberOfCameras; i++) {
Camera.getCameraInfo(i, cameraInfo);
if (cameraInfo.facing == CameraInfo.CAMERA_FACING_FRONT) {
cameraId = i;
}
}
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
return mCameraExtraction;
}
@Override
public void onResume() {
super.onResume();
// Use mCurrentCamera to select the camera desired to safely restore
// the fragment after the camera has been changed
mCamera = Camera.open(cameraId);
mCameraExtraction.setCamera(mCamera);
}
@Override
public void onPause() {
super.onPause();
if (mCamera != null)
{
mCamera.release();
}
}
// Modo en el que se pinta la cámara: encajada por dentro o saliendo los bordes por fuera.
public enum CameraViewMode {
/**
* Inner mode
*/
Inner,
/**
* Outer mode
*/
Outer
}
}
public class CameraExtraction extends ViewGroup implements SurfaceHolder.Callback {
private final String TAG = "CameraExtraction";
Camera mCamera;
SurfaceHolder mHolder;
SurfaceView mSurfaceView;
int mNumberOfCameras;
int cameraId;
Rect desiredSize;
CameraViewMode cameraViewMode;
boolean mSurfaceCreated = false;
List<Size> mSupportedPreviewSizes;
int rotation;
Size mPreviewSize;
public CameraExtraction(Context context, int rotation) {
super(context);
this.rotation = rotation;
mSurfaceView = new SurfaceView(context);
addView(mSurfaceView);
// Install a SurfaceHolder.Callback so we get notified when the
mHolder = mSurfaceView.getHolder();
mHolder.addCallback(this);
mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
cameraViewMode = CameraViewMode.Inner;
}
public void setCamera(Camera camera) {
mCamera = camera;
if (mCamera != null) {
mSupportedPreviewSizes = mCamera.getParameters().getSupportedPreviewSizes();
if (mSurfaceCreated) requestLayout();
}
}
public void switchCamera(Camera camera) {
setCamera(camera);
try {
camera.setPreviewDisplay(mHolder);
} catch (IOException exception) {
Log.e(TAG, "IOException caused by setPreviewDisplay()", exception);
}
}
@SuppressLint("DrawAllocation")
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
if (mSurfaceView == null ||mSurfaceView.getHolder() == null) return;
if (mSurfaceView.getHolder().getSurface() == null) {
// preview surface does not exist
return;
}
final int width = resolveSize(getSuggestedMinimumWidth(),
widthMeasureSpec);
final int height = resolveSize(getSuggestedMinimumHeight(),
heightMeasureSpec);
setMeasuredDimension(width, height);
if (mSupportedPreviewSizes != null) {
mPreviewSize = getNearestPreviewSize(mCamera.new Size(widthMeasureSpec,heightMeasureSpec));
}
if (mCamera != null) {
Camera.Parameters parameters = mCamera.getParameters();
parameters.setPreviewSize(mPreviewSize.width, mPreviewSize.height);
mCamera.setParameters(parameters);
}
}
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
if (getChildCount() > 0) {
final View child = getChildAt(0);
final int width = r - l;
final int height = b - t;
int previewWidth = width;
int previewHeight = height;
if (mPreviewSize != null) {
previewWidth = mPreviewSize.width;
previewHeight = mPreviewSize.height;
}
// Center the child SurfaceView within the parent.
if (width * previewHeight > height * previewWidth) {
final int scaledChildWidth = previewWidth * height
/ previewHeight;
child.layout((width - scaledChildWidth) / 2, 0,
(width + scaledChildWidth) / 2, height);
} else {
final int scaledChildHeight = previewHeight * width
/ previewWidth;
child.layout(0, (height - scaledChildHeight) / 2, width,
(height + scaledChildHeight) / 2);
}
}
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
mCamera = Camera.open(cameraId);
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width,int height) {
if (mSurfaceView == null || mSurfaceView.getHolder() == null) return;
if (mSurfaceView.getHolder().getSurface() == null) {
// preview surface does not exist
return;
}
// set preview size and make any resize, rotate or
// reformatting changes here
Camera.Parameters param = mCamera.getParameters();
Point previewSize = new Point(640,480);
Camera.Size size = getNearestPreviewSize(mCamera.new Size(previewSize.x,previewSize.y));
param.setPreviewSize(size.width, size.height);
mCamera.setParameters(param);
rotation = setCameraDisplayOrientation(cameraId, mCamera);
// start preview with new settings
try {
mCamera.setPreviewCallback(new Camera.PreviewCallback() {
@Override
public void onPreviewFrame(byte[] data, Camera camera) {
// TODO Auto-generated method stub
}
});
mCamera.setPreviewDisplay(mSurfaceView.getHolder());
mCamera.startPreview();
} catch (Exception e) {
Log.d("AndroidControlSurfaceView",
"Error starting camera preview: " + e.getMessage());
}
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
if (mCamera != null)
{
mCamera.stopPreview();
mCamera.release();
}
}
protected Rect getCameraViewSizeCompensated(Camera.Size cameraPreviewSize, Point hostViewSize) {
Rect toReturn=null;
float ratioWidth = hostViewSize.x / (float)cameraPreviewSize.width;
float ratioHeight = hostViewSize.y / (float)cameraPreviewSize.height;
switch (cameraViewMode){
case Inner:
if (ratioWidth < ratioHeight) {
int newHeight = (int)(cameraPreviewSize.height*ratioWidth);
int y = (hostViewSize.y - newHeight) / 2;
toReturn = new Rect(0, y, hostViewSize.x, y+newHeight);
} else {
int newWidth = (int)(cameraPreviewSize.width*ratioHeight);
int x = (hostViewSize.x - newWidth) / 2;
toReturn = new Rect(x, 0, x+newWidth,hostViewSize.y);
}
break;
case Outer:
if (ratioWidth < ratioHeight) {
int newWidth = (int)(cameraPreviewSize.width*ratioHeight);
int x = (hostViewSize.x - newWidth) / 2;
toReturn = new Rect(x, 0, x+newWidth,hostViewSize.y);
} else {
int newHeight = (int)(cameraPreviewSize.height*ratioWidth);
int y = (hostViewSize.y - newHeight) / 2;
toReturn = new Rect(0, y, hostViewSize.x, y+newHeight);
}
break;
}
return toReturn;
}
private Camera.Size getNearestPreviewSize(Camera.Size size) {
List<Camera.Size> availableSizes = mCamera.getParameters().getSupportedPreviewSizes();
if (availableSizes == null || availableSizes.size() <= 0) return null;
Camera.Size toReturn = availableSizes.get(0);
int distance = Math.abs(size.width*size.height - toReturn.width*toReturn.height);
for (int a=1; a<availableSizes.size(); a++) {
int temp = Math.abs(size.width*size.height - availableSizes.get(a).width*availableSizes.get(a).height);
if (temp < distance) {
distance = temp;
toReturn = availableSizes.get(a);
}
}
return toReturn;
}
public int setCameraDisplayOrientation(int cameraId, android.hardware.Camera camera) {
CameraInfo info = new Camera.CameraInfo();
Camera.getCameraInfo(cameraId, info);
int degrees = 0;
switch (rotation) {
case Surface.ROTATION_0: degrees = 0; break;
case Surface.ROTATION_90: degrees = 90; break;
case Surface.ROTATION_180: degrees = 180; break;
case Surface.ROTATION_270: degrees = 270; break;
}
int result;
if (info.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) {
result = (info.orientation + degrees) % 360;
result = (360 - result) % 360; // compensate the mirror
} else { // back-facing
result = (info.orientation - degrees + 360) % 360;
}
camera.setDisplayOrientation(result);
return result/90;
}
}
公共类CameraExtraction扩展了视图组，实现了SurfaceHolder.Callback{
私有最终字符串标记=“CameraExtraction”；
麦克默拉照相机；
表面粗糙度；
SurfaceView mSurfaceView；
国际货币基金组织；
int cameraId；
矩形所需尺寸；
CameraViewMode CameraViewMode；
布尔值mSurfaceCreated=false；
列出MSSupportedPreviewsizes；
整数旋转；
大小mPreviewSize；
公共摄影机提取（上下文、整数旋转）{
超级（上下文）；
这个旋转=旋转；
mSurfaceView=新的SurfaceView（上下文）；
addView（mSurfaceView）；
//安装SurfaceHolder.Callback，以便在
mHolder=mSurfaceView.getHolder（）；
mHolder.addCallback（this）；
mHolder.setType（SurfaceHolder.SURFACE\u TYPE\u PUSH\u缓冲区）；
cameraViewMode=cameraViewMode.internal；
}
公共摄像机（摄像机）{
mCamera=摄像机；
if（mCamera！=null）{
mSupportedPreviewSizes=mCamera.getParameters（）.getSupportedPreviewSizes（）；
如果（mSurfaceCreated）requestLayout（）；
}
}
公共摄像机（摄像机）{
设置摄像机（摄像机）；
试一试{
摄像头。设置预览显示（mHolder）；
}捕获（IOException异常）{
Log.e（标记“setPreviewDisplay（）引起的IOException”，exception）；
}
}
@SuppressLint（“DrawAllocation”）
@凌驾
测量时的保护空隙（内部宽度测量等级、内部高度测量等级）{
if（mSurfaceView==null | | mSurfaceView.getHolder（）==null）返回；
if（mSurfaceView.getHolder（）.getSurface（）==null）{
//预览曲面不存在
返回；
}
最终整数宽度=resolveSize（getSuggestedMinimumWidth（），
宽度（特殊）；
最终整数高度=resolveSize（getSuggestedMinimumHeight（），
高度测量（特殊）；
设置测量尺寸（宽度、高度）；
if（mSupportedPreviewSizes！=null）{
mPreviewSize=getNearestPreviewSize（mCamera.new Size（widthmasurespec，heightMeasureSpec））；
}
if（mCamera！=null）{
Camera.Parameters=mCamera.getParameters（）；
parameters.setPreviewSize（mPreviewSize.width、mPreviewSize.height）；
mCamera.setParameters（参数）；
}
}
@凌驾
仅受保护的void布局（布尔值已更改、int l、int t、int r、int b）{
如果（getChildCount（）>0）{
最终视图子对象=getChildAt（0）；
最终整数宽度=r-l；
最终内部高度=b-t；
int previewWidth=宽度；
亮度=高度；
if（mPreviewSize！=null）{
previewWidth=mPreviewSize.width；
PreviewView=mPreviewSize.height；
}
//将子曲面视图居中放置在父曲面视图中。
如果（宽度*预览宽度>高度*预览宽度）{
最终整数scaledChildWidth=预览宽度*高度
/预演；
布局（（宽度-scaledChildWidth）/2,0，
（宽度+缩放儿童宽度）/2，高度）；
}否则{
最终int scaledChildHeight=预览视图*宽度
/预览宽度；
布局（0，（高度-缩放儿童高度）/2，宽度，
（身高+缩放儿童身高）/2）；
}
}
}
@凌驾
已创建的公共空白表面（表面持有人）{
mCamera=Camera.open（cameraId）；
}
@凌驾
公共空白表面更改（表面文件夹持有者、整型格式、整型宽度、整型高度）{
if（mSurfaceView==null | | mSurfaceView.getHolder（）==null）返回；
if（mSurfaceView.getHolder（）.getSurface（）==null）{
//预览曲面不存在
返回；
}
//设置预览大小并进行任何调整大小、旋转或
//在此处重新格式化更改
Camera.Parameters param=mCamera.getParameters（）；
点预览大小=新点（640480）；
Camera.Size Size=getNearestPreviewSize（mCamera.new Size）（previewSize.x，previ