Question

我需要通过使用传感器来了解设备是否接近耳朵

我尝试使用接近度，我想结合使用加速器和陀螺仪传感器，以确切地发现设备离耳朵很近或远离。

接近代码

@覆盖 public void onSensorChanged（SensorEvent event）{

    float distance = event.values[0];

    if (event.sensor.getType() == Sensor.TYPE_PROXIMITY) {
        if (distance < mProximity.getMaximumRange()) {
            iv.setText("Near");
        } else {
            iv.setText("far");
        }
    }
}

Answer 1

这是我从Android Documentation得到的，我相信你可以挖掘更多来解决你的问题，但这应该足以让你开始。你也可以在android中对位置传感器做一些研究。文档非常有用

// Create a constant to convert nanoseconds to seconds.
private static final float NS2S = 1.0f / 1000000000.0f;
private final float[] deltaRotationVector = new float[4]();
private float timestamp;

public void onSensorChanged(SensorEvent event) {
// This timestep's delta rotation to be multiplied by the current rotation
// after computing it from the gyro sample data.
if (timestamp != 0) {
    final float dT = (event.timestamp - timestamp) * NS2S;
    // Axis of the rotation sample, not normalized yet.    
    float axisX = event.values[0];
    float axisY = event.values[1];
    float axisZ = event.values[2];

    // Calculate the angular speed of the sample
    float omegaMagnitude = sqrt(axisX*axisX + axisY*axisY + axisZ*axisZ);

    // Normalize the rotation vector if it's big enough to get the axis
    // (that is, EPSILON should represent your maximum allowable margin of error)
    if (omegaMagnitude > EPSILON) {
      axisX /= omegaMagnitude;
      axisY /= omegaMagnitude;
      axisZ /= omegaMagnitude;
    }

    // Integrate around this axis with the angular speed by the timestep
    // in order to get a delta rotation from this sample over the timestep
    // We will convert this axis-angle representation of the delta rotation
    // into a quaternion before turning it into the rotation matrix.
    float thetaOverTwo = omegaMagnitude * dT / 2.0f;
    float sinThetaOverTwo = sin(thetaOverTwo);
    float cosThetaOverTwo = cos(thetaOverTwo);
    deltaRotationVector[0] = sinThetaOverTwo * axisX;
    deltaRotationVector[1] = sinThetaOverTwo * axisY;
    deltaRotationVector[2] = sinThetaOverTwo * axisZ;    
    deltaRotationVector[3] = cosThetaOverTwo;
  }
  timestamp = event.timestamp;
  float[] deltaRotationMatrix = new float[9];
  SensorManager.getRotationMatrixFromVector(deltaRotationMatrix,
                              deltaRotationVector);
// User code should concatenate the delta rotation we computed with the current rotation
// in order to get the updated rotation.
// rotationCurrent = rotationCurrent * deltaRotationMatrix;
   }
}

将设备检测到接近或远离Ear Android代码

1 个答案: