我的相机应用程序出了问题。 我的应用有：
1）CameraActivity.class和
2）CameraPreview.class。
CameraPreview实现一个surfaceView，从CameraActivity调用它来进行实际预览。 （也在CameraActivity我有参数）
现在出现问题：预览开始时，预览会被拉伸。 我尝试了很多东西（很多我都记不住了） 我需要有人告诉我写什么和在哪里。提前谢谢。
这是CameraActivity（不是所有代码，但我认为重要）
private PictureCallback mPicture = new PictureCallback() {
public void onPictureTaken(byte[] data, Camera camera) {
// Replacing the button after a photho was taken.
flBtnContainer.setVisibility(View.GONE);
ibRetake.setVisibility(View.VISIBLE);
ibUse.setVisibility(View.VISIBLE);
// File name of the image that we just took.
fileName = "IMG_" + new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date()).toString() + ".jpg";
// Creating the directory where to save the image. Sadly in older
// version of Android we can not get the Media catalog name
File mkDir = new File(sdRoot, dir);
mkDir.mkdirs();
// Main file where to save the data that we recive from the camera
File pictureFile = new File(sdRoot, dir + fileName);
try {
FileOutputStream purge = new FileOutputStream(pictureFile);
purge.write(data);
purge.close();
} catch (FileNotFoundException e) {
Log.d("DG_DEBUG", "File not found: " + e.getMessage());
} catch (IOException e) {
Log.d("DG_DEBUG", "Error accessing file: " + e.getMessage());
}
// Adding Exif data for the orientation. For some strange reason the
// ExifInterface class takes a string instead of a file.
try {
exif = new ExifInterface("/sdcard/" + dir + fileName);
exif.setAttribute(ExifInterface.TAG_ORIENTATION, "" + orientation);
exif.saveAttributes();
} catch (IOException e) {
e.printStackTrace();
}
Intent intent = new Intent(CameraActivity.this, PicturePreview.class);
Bundle extras = new Bundle();
extras.putString("ImagePath", String.valueOf(pictureFile));
intent.putExtras(extras);
startActivity(intent);
//SendBroadcasts let's us instantly update the SD card with our image
sendBroadcast(new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE, Uri.parse("file://"+Environment.getExternalStorageDirectory())));
}
};
private void createCamera() {
// Create an instance of Camera
mCamera = getCameraInstance();
// Setting the right parameters in the camera
Camera.Parameters params = mCamera.getParameters();
params.setRotation(90);
mCamera.setParameters(params);
// Create our Preview view and set it as the content of our activity.
mPreview = new CameraPreview(this, mCamera);
FrameLayout preview = (FrameLayout) findViewById(R.id.camera_preview);
preview.addView(mPreview, 0);
}
@Override
protected void onResume() {
super.onResume();
// Test if there is a camera on the device and if the SD card is
// mounted.
if (!checkCameraHardware(this)) {
Intent i = new Intent(this, NoCamera.class);
startActivity(i);
finish();
} else if (!checkSDCard()) {
Intent i = new Intent(this, NoSDCard.class);
startActivity(i);
finish();
}
// Creating the camera
createCamera();
// Register this class as a listener for the accelerometer sensor
////sensorManager.registerListener(this, sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_NORMAL);
}
@Override
protected void onPause() {
super.onPause();
// release the camera immediately on pause event
releaseCamera();
// removing the inserted view - so when we come back to the app we
// won't have the views on top of each other.
FrameLayout preview = (FrameLayout) findViewById(R.id.camera_preview);
preview.removeViewAt(0);
}
这是CameraPreview.class
public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {
private SurfaceHolder mHolder;
private Camera mCamera;
boolean isPreviewRunning = true;
public CameraPreview(Context context, Camera camera) {
super(context);
mCamera = camera;
// Install a SurfaceHolder.Callback so we get notified when the
// underlying surface is created and destroyed.
mHolder = getHolder();
mHolder.addCallback(this);
// deprecated setting, but required on Android versions prior to 3.0
mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
mHolder.setFixedSize(100, 100);
}
public void surfaceCreated(SurfaceHolder holder) {
// The Surface has been created, now tell the camera where to draw the
// preview.
try {
mCamera.setPreviewDisplay(holder);
mCamera.setDisplayOrientation(90);
mCamera.startPreview();
} catch (IOException e) {
Log.d("DG_DEBUG", "Error setting camera preview: " + e.getMessage());
}
}
public void surfaceChanged(SurfaceHolder holder,
int format, int width, int height) {
if (isPreviewRunning){
return;
}
isPreviewRunning = true;
// If your preview can change or rotate, take care of those events here.
// Make sure to stop the preview before resizing or reformatting it.
if (mHolder.getSurface() == null) {
// preview surface does not exist
return;
}
// stop preview before making changes
try {
mCamera.stopPreview();
} catch (Exception e) {
// ignore: tried to stop a non-existent preview
}
// make any resize, rotate or reformatting changes here
// start preview with new settings
try {
mCamera.setPreviewDisplay(mHolder);
mCamera.startPreview();
} catch (Exception e) {
Log.d("DG_DEBUG", "Error starting camera preview: " + e.getMessage());
}
}
public void surfaceDestroyed(SurfaceHolder holder) {
// empty. Take care of releasing the Camera preview in your activity.
}
}
有人能说出我错过了什么吗？如果可能的话，我可以在Facebook或其他地方聊天，以便更快地解决我的问题..
更新：@ LikeWhiteOnRice的解决方案。
这是我的原始代码
以下是LikeWhiteOnRice的代码：
有什么想法吗？
答案 0 :(得分：1)
我将下面的代码添加到我的相机预览课程中，它适用于大多数设备。正如您所知，Android中的相机库非常糟糕，并且非常难以使用。
将此功能放在CameraPreview类中：
private Camera.Size getOptimalSize(List<Camera.Size> sizes, int h, int w) {
final double ASPECT_TOLERANCE = 0.05;
double targetRatio = (double) w/h;
if (sizes == null) {
return null;
}
Camera.Size optimalSize = null;
double minDiff = Double.MAX_VALUE;
int targetHeight = h;
for (Camera.Size size : sizes) {
double ratio = (double) size.width / size.height;
if (Math.abs(ratio - targetRatio) > ASPECT_TOLERANCE) continue;
if (Math.abs(size.height - targetHeight) < minDiff) {
optimalSize = size;
minDiff = Math.abs(size.height - targetHeight);
}
}
if (optimalSize == null) {
minDiff = Double.MAX_VALUE;
for (Camera.Size size : sizes) {
if (Math.abs(size.height - targetHeight) < minDiff) {
optimalSize = size;
minDiff = Math.abs(size.height - targetHeight);
}
}
}
return optimalSize;
}
在您的surefaceCreated函数中，在开始预览之前添加：
Camera.Parameters cameraParameters = mCamera.getParameters();
List<Camera.Size> previewSizes = cameraParameters.getSupportedPreviewSizes();
Camera.Size optimalPreviewSize = getOptimalSize(previewSizes, getResources().getDisplayMetrics().widthPixels, getResources().getDisplayMetrics().heightPixels);
cameraParameters.setPreviewSize(optimalPreviewSize.width, optimalPreviewSize.height);
mCamera.setParameters(cameraParameters);
编辑：另外，我不确定你是否想要
mHolder.setFixedSize(100, 100);
在你的构造函数中。