我正在开展一个项目,我希望在设备移动时拍照,以便创建全景图像本身。一旦陀螺力超过阈值,我希望相机拍照。我有失败的保险箱,所以一次只拍摄一张照片,但我不知道它为什么会失败。
这是我的主要活动代码:
public class MainActivity extends Activity implements SensorEventListener {
static CameraPreview mPreview;
Camera mCamera;
static TextView pCount;
public SensorManager sensorManager;
public Sensor gyroscope;
public float xGyro;
public float yGyro;
public float zGyro;
public TextView xG;
public TextView yG;
public TextView zG;
public static double PHOTOTHRESHOLD = 1;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Create an instance of Camera
mCamera = getCameraInstance();
// 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);
pCount = (TextView) findViewById(R.id.pictureCount);
sensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
gyroscope = sensorManager.getDefaultSensor(Sensor.TYPE_GYROSCOPE);
xG = (TextView) findViewById(R.id.xG);
yG = (TextView) findViewById(R.id.yG);
zG = (TextView) findViewById(R.id.zG);
}
public static void capture(){
mPreview.capturePicture();
}
/** A safe way to get an instance of the Camera object. */
public static Camera getCameraInstance(){
Camera c = null;
try {
c = Camera.open(); // attempt to get a Camera instance
}
catch (Exception e){
// Camera is not available (in use or does not exist)
}
return c; // returns null if camera is unavailable
}
@Override
public void onSensorChanged(SensorEvent event) {
xGyro = event.values[0];
yGyro = event.values[1];
zGyro = event.values[2];
xG.setText(String.valueOf(xGyro));
yG.setText(String.valueOf(yGyro));
zG.setText(String.valueOf(zGyro));
if(xGyro > PHOTOTHRESHOLD || yGyro > PHOTOTHRESHOLD || zGyro > PHOTOTHRESHOLD){
capture();
}
}
@Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
}
@Override
protected void onResume(){
super.onResume();
sensorManager.registerListener(this, gyroscope, SensorManager.SENSOR_DELAY_NORMAL);
}
@Override
protected void onPause() {
super.onPause();
sensorManager.unregisterListener(this);
}
}
和cameraPreview类的代码
public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {
private SurfaceHolder mHolder;
private Camera mCamera;
public boolean safeToTakePicture;
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);
}
public void surfaceCreated(SurfaceHolder holder) {
// The Surface has been created, now tell the camera where to draw the preview.
try {
mCamera.setPreviewDisplay(holder);
mCamera.startPreview();
safeToTakePicture = true;
} catch (IOException e) {
Log.d("CAMERA", "Error setting camera preview: " + e.getMessage());
}
}
public void surfaceDestroyed(SurfaceHolder holder) {
// empty. Take care of releasing the Camera preview in your activity.
}
public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
// 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
}
// set preview size and make any resize, rotate or
// reformatting changes here
// start preview with new settings
try {
mCamera.setPreviewDisplay(mHolder);
mCamera.startPreview();
} catch (Exception e){
Log.d("CAMERA", "Error starting camera preview: " + e.getMessage());
}
}
private Camera.PictureCallback mPicture = new Camera.PictureCallback() {
@Override
public void onPictureTaken(byte[] data, Camera camera) {
safeToTakePicture = true;
}
};
public void capturePicture() {
if(safeToTakePicture) {
safeToTakePicture = false;
mCamera.takePicture(null, null, mPicture);
}
}
}
我的错误是:
Process: rimodel.streampictures, PID: 21185
java.lang.RuntimeException: takePicture failed
at android.hardware.Camera.native_takePicture(Native Method)
at android.hardware.Camera.takePicture(Camera.java:1436)
at android.hardware.Camera.takePicture(Camera.java:1381)
at rimodel.streampictures.CameraPreview.capturePicture(CameraPreview.java:114)
at rimodel.streampictures.MainActivity.capture(MainActivity.java:70)
at rimodel.streampictures.MainActivity.onSensorChanged(MainActivity.java:98)
at android.hardware.SystemSensorManager$SensorEventQueue.dispatchSensorEvent(SystemSensorManager.java:405)
at android.os.MessageQueue.nativePollOnce(Native Method)
at android.os.MessageQueue.next(MessageQueue.java:143)
at android.os.Looper.loop(Looper.java:122)
at android.app.ActivityThread.main(ActivityThread.java:5254)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
我知道我在主线程上有很多事情,但我认为这不足以让程序崩溃。
非常感谢任何帮助
答案 0 :(得分:2)
我想通了......
如果遇到类似问题,请务必再次开始预览。
private Camera.PictureCallback mPicture = new Camera.PictureCallback() {
@Override
public void onPictureTaken(byte[] data, Camera camera) {
mCamera.startPreview();
safeToTakePicture = true;