我试图为研究创建一个简单的相机应用程序。 我阅读Android Camera Official Document然后开始编码。 所以我采取了一些措施让它发挥作用
1.在应用中添加了相机功能所需的权限。
2.仅将我的活动锁定到PORTRAIT模式。
setRequestedOrientation（ActivityInfo.SCREEN_ORIENTATION_PORTRAIT）;
3.增加了几个相机回调以使相机正常工作。
4.在 surfaceChanged 方法中，我正在自定义相机设置。 到目前为止，我已经为几乎所有的Android设备工作了
但是然后我在Android版本2.3.6上测试三星Galaxy ACE 并发现相机显示预览已旋转为横向模式。
所以在输入log-cat / break点之后我才知道以下方法对于这个特定的模型不起作用
//This method is not working for Samsung Galaxy ACE
camera.setDisplayOrientation(90);
//or
parameters.set("orientation", "portrait");
//or
parameters.setRotation(90);
注意： 我在Google和SO上搜索了大量解决方案，但到目前为止还没有运气好
供参考我的示例代码位于
之下@Override
public void surfaceChanged(SurfaceHolder arg0, int arg1, int arg2, int arg3) {
Log.v(TAG, "surfaceChanged get called");
if (previewing) {
camera.stopPreview();
previewing = false;
}
if (camera != null) {
try {
Camera.Parameters parameters = camera.getParameters();
List<Size> sizes = parameters.getSupportedPictureSizes();
Camera.Size result = null;
for (int i = 0; i < sizes.size(); i++) {
result = (Size) sizes.get(i);
Log.i("PictureSize", "Supported Size. Width: "
+ result.width + "height : " + result.height);
if (result.width == 640) {
parameters.setPreviewSize(result.width, result.height);// 640*480
parameters.setPictureSize(result.width, result.height);
} else {
}
}
//**************************************************************//
/*
* Here is the logic I have added to Manage Camera Display Orientation
* It checks Current Orientation and SDK and then rotate display to make it Portrait view.
*/
int currentSDKVersion = android.os.Build.VERSION.SDK_INT;
Log.d(TAG, "currentVersion " + currentSDKVersion);
if (getResources().getConfiguration().orientation == Configuration.ORIENTATION_PORTRAIT) {
if (currentSDKVersion != 7) {
camera.setDisplayOrientation(90);
parameters.setRotation(90);
} else {
parameters.setRotation(90);
/*
* params.set("orientation", "portrait");
* params.set("rotation",90);
*/
}
} else if (getResources().getConfiguration().orientation == Configuration.ORIENTATION_LANDSCAPE) {
if (currentSDKVersion != 7) {
camera.setDisplayOrientation(0);
} else {
parameters.set("orientation", "landscape");
parameters.set("rotation", 90);
}
}
//**************************************************************//
camera.setParameters(parameters);
camera.setPreviewDisplay(surfaceHolder);
camera.startPreview();
camera.autoFocus(myAutoFocusCallback);
camera.setOneShotPreviewCallback(cameraPreviewCallback);
previewing = true;
} catch (IOException e) {
e.printStackTrace();
}
}
}
我的相机活动（MainActivity.java）完整代码是：
public class MainActivity extends Activity implements SurfaceHolder.Callback,
OnClickListener {
public static final String TAG = "CameraActivity";
private Context context = null;
Camera camera = null;
private SurfaceView surfaceView = null;
private SurfaceHolder surfaceHolder = null;
boolean previewing = false;
private LayoutInflater controlInflater = null;
private Button buttonTakePicture = null;
//private TextView textViewResultInfo = null;
@SuppressWarnings("deprecation")
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Log.v(TAG, "onCreate get called");
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
//textViewResultInfo = (TextView) findViewById(R.id.textViewResultInfo);
context = this;
getWindow().setFormat(PixelFormat.UNKNOWN);
surfaceView = (SurfaceView) findViewById(R.id.surfaceview);
surfaceHolder = surfaceView.getHolder();
surfaceHolder.addCallback(this);
surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
controlInflater = LayoutInflater.from(getBaseContext());
View viewControl = controlInflater.inflate(R.layout.control, null);
LayoutParams layoutParamsControl = new LayoutParams(
LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT);
this.addContentView(viewControl, layoutParamsControl);
buttonTakePicture = (Button) findViewById(R.id.takepicture);
buttonTakePicture.setOnClickListener(this);
}
@Override
public void surfaceCreated(SurfaceHolder arg0) {
Log.v(TAG, "surfaceCreated get called");
camera = Camera.open();
if (camera != null) {
try {
camera.setPreviewDisplay(surfaceHolder);
camera.startPreview();
previewing = true;
} catch (IOException e) {
e.printStackTrace();
}
}
}
@Override
public void surfaceChanged(SurfaceHolder arg0, int arg1, int arg2, int arg3) {
Log.v(TAG, "surfaceChanged get called");
if (previewing) {
camera.stopPreview();
previewing = false;
}
if (camera != null) {
try {
//new MainActivity().setCameraDisplayOrientation();
Camera.Parameters parameters = camera.getParameters();
// List<String> focusModes =
// parameters.getSupportedFocusModes();
// if (focusModes.contains(Camera.Parameters.FOCUS_MODE_AUTO))
// {
// parameters.setFocusMode(Camera.Parameters.FOCUS_MODE_AUTO);
// }
List<Size> sizes = parameters.getSupportedPictureSizes();
Camera.Size result = null;
for (int i = 0; i < sizes.size(); i++) {
result = (Size) sizes.get(i);
Log.i("PictureSize", "Supported Size. Width: "
+ result.width + "height : " + result.height);
if (result.width == 640) {
parameters.setPreviewSize(result.width, result.height);// 640*480
parameters.setPictureSize(result.width, result.height);
} else {
}
}
//**************************************************************//
Display display = ((WindowManager) context.getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
int rotation = display.getRotation();
Log.v(TAG, "Current Device Orientation is ="+rotation);
/*
* Here is the logic I have added to Manage Camera Display Orientation
* It checks Current Orientation and SDK and then rotate display to make it Portrait view.
*/
int currentSDKVersion = android.os.Build.VERSION.SDK_INT;
Log.d(TAG, "currentVersion " + currentSDKVersion);
if (getResources().getConfiguration().orientation == Configuration.ORIENTATION_PORTRAIT) {
if (currentSDKVersion != 7) {
Log.i(TAG, "ORIENTATION_PORTRAIT +SDK is: " + currentSDKVersion
+ "rotate 90");
camera.setDisplayOrientation(90);
parameters.setRotation(90);
} else {
Log.i(TAG, "ORIENTATION_PORTRAIT +SDK is: " + currentSDKVersion
+ "rotate 90");
parameters.setRotation(90);
/*
* params.set("orientation", "portrait");
* params.set("rotation",90);
*/
}
} else if (getResources().getConfiguration().orientation == Configuration.ORIENTATION_LANDSCAPE) {
if (currentSDKVersion != 7) {
Log.i(TAG, "ORIENTATION_LANDSCAPE +SDK is: " + currentSDKVersion
+ "rotate 90");
camera.setDisplayOrientation(0);
} else {
Log.i(TAG, "ORIENTATION_LANDSCAPE +SDK is: " + currentSDKVersion
+ "rotate 90");
parameters.set("orientation", "landscape");
parameters.set("rotation", 90);
}
}
//**************************************************************//
camera.setParameters(parameters);
camera.setPreviewDisplay(surfaceHolder);
camera.startPreview();
camera.autoFocus(myAutoFocusCallback);
camera.setOneShotPreviewCallback(cameraPreviewCallback);
previewing = true;
} catch (IOException e) {
e.printStackTrace();
}
}
}
@Override
public void surfaceDestroyed(SurfaceHolder arg0) {
Log.v(TAG, "surfaceDestroyed get called");
camera.stopPreview();
camera.release();
camera = null;
previewing = false;
}
public void setCameraDisplayOrientation()
{
Log.v(TAG, "setCameraDisplayOrientation get called");
if (camera == null)
{
Log.d(TAG,"setCameraDisplayOrientation - camera null");
return;
}
Camera.CameraInfo info = new Camera.CameraInfo();
Camera.getCameraInfo(1, info);
WindowManager winManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
int rotation = winManager.getDefaultDisplay().getRotation();
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);
}
@Override
public void onClick(View v) {
Log.v(TAG, "onClick get called");
if (v == buttonTakePicture) {
camera.takePicture(myShutterCallback, myPictureCallback_RAW,
myPictureCallback_JPG);
}
}
private Camera.PreviewCallback cameraPreviewCallback = new Camera.PreviewCallback() {
@Override
public void onPreviewFrame(byte[] data, Camera camera) {
Log.i(TAG, "onPreviewFrame size=" + data.length);
}
};
AutoFocusCallback myAutoFocusCallback = new AutoFocusCallback() {
@Override
public void onAutoFocus(boolean arg0, Camera arg1) {
Log.v(TAG, "onAutoFocus get called");
buttonTakePicture.setEnabled(true);
}
};
ShutterCallback myShutterCallback = new ShutterCallback() {
@Override
public void onShutter() {
Log.v(TAG, "onShutter get called");
}
};
PictureCallback myPictureCallback_RAW = new PictureCallback() {
@Override
public void onPictureTaken(byte[] arg0, Camera arg1) {
Log.v(TAG, "onPictureTaken-RAW get called");
}
};
public static Bitmap RotateBitmap(Bitmap source, float angle) {
Matrix matrix = new Matrix();
matrix.postRotate(angle);
return Bitmap.createBitmap(source, 0, 0, source.getWidth(),
source.getHeight(), matrix, true);
}
PictureCallback myPictureCallback_JPG = new PictureCallback() {
@Override
public void onPictureTaken(byte[] arg0, Camera arg1) {
Bitmap rawImage = BitmapFactory.decodeByteArray(arg0, 0,
arg0.length);
if (getResources().getConfiguration().orientation == Configuration.ORIENTATION_PORTRAIT) {
Log.v(TAG, "##### ORIENTATION_PORTRAIT ####");
rawImage = MainActivity.RotateBitmap(rawImage, 90);
ByteArrayOutputStream stream = new ByteArrayOutputStream();
rawImage.compress(Bitmap.CompressFormat.JPEG, 100, stream);
arg0 = stream.toByteArray();
} else if (getResources().getConfiguration().orientation == Configuration.ORIENTATION_LANDSCAPE) {
Log.v(TAG, "##### ORIENTATION_LANDSCAPE #####");
}
Intent intent = new Intent(MainActivity.this, ResultActivity.class);
intent.putExtra("picture", arg0);
startActivity(intent);
Log.v(TAG, "onPictureTaken-JPG get called");
}
};
/**
* Get the size in bitmap.
*
* @param bitmap
* @return size in bytes
*/
@TargetApi(12)
public static int getBitmapSize(Bitmap bitmap) {
if (MainActivity.hasHoneycombMR1()) {
return bitmap.getByteCount();
}
// Pre HC-MR1
return bitmap.getRowBytes() * bitmap.getHeight();
}
public static boolean hasHoneycombMR1() {
return Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB_MR1;
}
}
修改：我发表了对Developer forum的评论，但没有回复。
请!!有人对这个问题有任何想法。
我真的很感激任何建议。
答案 0 :(得分：9)
当我遇到与运行2.2.1的原始Galaxy Tab类似的问题时，我能够通过执行以下操作来解决它：
Camera.Parameters parameters = camera.getParameters();
parameters.set("orientation", "portrait");
parameters.setRotation(90);
camera.setParameters(parameters);
但是，看起来你可能已经尝试过这种确切的组合，因为你有相同的（但已注释掉的）代码。但是，你现在拥有代码的方式，由于它的API级别（1），Ace会绕过你所注释代码的位置。在这个区块内专门尝试：
if (currentSDKVersion != 7) { }
请告诉我它是否有效。谢谢！
答案 1 :(得分：0)
我也在寻找一个小时的解决方案。它真的很疯狂。 我的解决方案是在横向模式下（在我的人像应用程序中）使用相机预览，并屏蔽我不需要的预览部分。我通过将我的全屏预览的上下部分与一些视图重叠来完成此操作。因为你必须裁剪你从相机获得的照片，然后，结果很少解决。对于我的应用程序，这不是问题。
我现在对我的解决方案非常满意 - 用户看不出任何差异;
答案 2 :(得分：0)
我通过编写一些主要改编自ZXing项目的代码来处理相机：http://code.google.com/p/zxing/
您可以尝试使用它们。如果您尝试使用此功能，我建议您仔细阅读此stackoverflow question
的解决方案这可能不是您问题的完美解决方案，但我已经解决了这个问题，并决定使用Zxing。