我正在构建我的第一个应用程序，我想在按下按钮并且手机不动时获得手机的方向。用户可以看到后置摄像头的视图，指向然后按下按钮，应该得到角度。
当我在中使用它时，该代码似乎可以正常工作onSensorChanged（我将其用作示例代码：使用 getRotationMatrix() 和 getOrientation() 查找方向），但是当我在“onClick”中使用它时会崩溃。
我想获得其他计算的音高值（我制作了音高全局变量）。这是我的onClick代码：
public void onClick(View arg0)
{
camera.takePicture(myShutterCallback,
myPictureCallback_RAW, myPictureCallback_JPG);
switch (event.sensor.getType()) {
case Sensor.TYPE_ACCELEROMETER:
gravity = event.values.clone();
break;
case Sensor.TYPE_MAGNETIC_FIELD:
magnet = event.values.clone();
break;
}
if(gravity!=null && magnet!=null) {
rotMatrix = SensorManager.getRotationMatrix(inR, I, gravity, magnet);
SensorManager.remapCoordinateSystem(inR,
SensorManager.AXIS_X, SensorManager.AXIS_Z, outR);
SensorManager.getOrientation(outR, orientVals);
float azimuth = orientVals[0]*rad2deg;
pitch = orientVals[1]*rad2deg;
float roll = orientVals[2]*rad2deg;
TextView rezDisplay = (TextView) findViewById(R.id.finalRezult);
rezDisplay.setText("Atstumas iki objekto yra:" + pitch + "m");
}
}
任何建议、链接、示例或 tuts 都会很棒。
编辑：
我添加了整个课程代码。
import java.io.IOException;
import com.mindjack.measuremydistance.SensorEvnt.mSensorEventListener;
import android.app.Activity;
//import android.content.Intent;
import android.content.Context;
import android.content.pm.ActivityInfo;
//import android.graphics.Bitmap;
//import android.graphics.BitmapFactory;
import android.graphics.PixelFormat;
import android.hardware.Camera;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorManager;
import android.hardware.Camera.PictureCallback;
import android.hardware.Camera.ShutterCallback;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.ViewGroup.LayoutParams;
import android.widget.Button;
import android.widget.TextView;
public class AndroidCamera extends Activity implements SurfaceHolder.Callback
{
Camera camera;
SurfaceView surfaceView;
SurfaceHolder surfaceHolder;
boolean previewing = false;
LayoutInflater controlInflater = null;
TextView display, display1;
float[] magnet = new float[3];
float[] gravity = new float[3];
SensorEvent event;
boolean rotMatrix;
float[] outR = new float[16];
float[] inR = new float[16];
float[] I = new float[16];
float[] orientVals = new float[3];
final float pi = (float) Math.PI;
final float rad2deg = 180/pi;
float pitch;
SensorManager mSensorManager;
/** Called when the activity is first created. */
@SuppressWarnings("deprecation")
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.andcam);
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
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);
mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
Button buttonTakePicture = (Button)findViewById(R.id.takepicture);
buttonTakePicture.setOnClickListener(new Button.OnClickListener() {
// TODO Auto-generated method stub
@Override
public void onClick(View arg0) {
camera.takePicture(myShutterCallback,
myPictureCallback_RAW, myPictureCallback_JPG);
switch (event.sensor.getType()){
case Sensor.TYPE_ACCELEROMETER:
gravity = event.values.clone();
break;
case Sensor.TYPE_MAGNETIC_FIELD:
magnet = event.values.clone();
break;
}
//if(gravity!=null && magnet!=null){
rotMatrix = SensorManager.getRotationMatrix(inR,
I, gravity, magnet);
SensorManager.remapCoordinateSystem(inR,
SensorManager.AXIS_X, SensorManager.AXIS_Z, outR);
SensorManager.getOrientation(outR, orientVals);
float azimuth = orientVals[0]*rad2deg;
pitch = orientVals[1]*rad2deg;
float roll = orientVals[2]*rad2deg;
// }
TextView rezDisplay = (TextView) findViewById(R.id.finalRezult);
rezDisplay.setText("Atstumas iki objekto yra:" + pitch + "m");
}
});
}
ShutterCallback myShutterCallback = new ShutterCallback() {
@Override
public void onShutter() {
// TODO Auto-generated method stub
}
};
PictureCallback myPictureCallback_RAW = new PictureCallback() {
@Override
public void onPictureTaken(byte[] arg0, Camera arg1) {
// TODO Auto-generated method stub
}
};
PictureCallback myPictureCallback_JPG = new PictureCallback() {
@Override
public void onPictureTaken(byte[] arg0, Camera arg1) {
// TODO Auto-generated method stub
//Bitmap bitmapPicture
//= BitmapFactory.decodeByteArray(arg0, 0, arg0.length);
}
};
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width,
int height)
{
// TODO Auto-generated method stub
if(previewing) {
camera.stopPreview();
previewing = false;
}
if (camera != null){
try {
camera.setPreviewDisplay(surfaceHolder);
camera.startPreview();
previewing = true;
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
// TODO Auto-generated method stub
camera = Camera.open();
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
// TODO Auto-generated method stub
camera.stopPreview();
camera.release();
camera = null;
previewing = false;
}
}
由于我是新手，可能会有一些愚蠢的错误，但我无法弄清楚这种情况。LogCat 说它在第 84 行崩溃。我试图从第 84 行到第 91 行取出部分，然后它没有崩溃，但在音高值上也给出了 0。