Posts from the ‘Projects’ Category

package uk.co.connorhd.android.tapemeasure;
 
import android.app.Activity;
import android.os.Bundle;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;
 
public class TapeMeasure extends Activity implements SensorEventListener,
		OnClickListener {
	private SensorManager sensorMgr;
	private Sensor sensorAccel;
	private TextView accuracyLabel;
	private TextView xLabel, yLabel, zLabel;
	private Button calibrateButton;
 
	private float moved = 0;
	private float speed = 0;
	private float accel = 0;
	private float accelDiff = 0;
 
	private float[] a;
 
	private long lastUpdate = 0;
	private float curAccel = 0;
	private int accelUpdates = 0;
 
	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main);
		accuracyLabel = (TextView) findViewById(R.id.accuracy_label);
		xLabel = (TextView) findViewById(R.id.x_label);
		yLabel = (TextView) findViewById(R.id.y_label);
		zLabel = (TextView) findViewById(R.id.z_label);
		calibrateButton = (Button) findViewById(R.id.calibrate_button);
		calibrateButton.setOnClickListener(this);
	}
 
	@Override
	protected void onPause() {
		super.onPause();
		sensorMgr.unregisterListener(this, sensorAccel);
		sensorMgr = null;
	}
 
	@Override
	protected void onResume() {
		super.onResume();
 
		sensorMgr = (SensorManager) getSystemService(SENSOR_SERVICE);
		sensorAccel = sensorMgr.getSensorList(Sensor.TYPE_ACCELEROMETER).get(0);
		boolean accelSupported = sensorMgr.registerListener(this, sensorAccel,
				SensorManager.SENSOR_DELAY_FASTEST);
 
		if (!accelSupported) {
			// on accelerometer on this device
			sensorMgr.unregisterListener(this, sensorAccel);
			accuracyLabel.setText(R.string.no_accelerometer);
		}
	}
 
	public void onClick(View v) {
		if (v == calibrateButton) {
			// Clicked button
			moved = 0;
			speed = 0;
			accelDiff = accel+accelDiff;
			accel = 0;
 
		}
	}
 
	public void onAccuracyChanged(Sensor sensor, int accuracy) {
		// this method is called very rarely, so we don't have to
		// limit our updates as we do in onSensorChanged(...)
		if (sensor.getType() == Sensor.TYPE_ACCELEROMETER) {
			switch (accuracy) {
			case SensorManager.SENSOR_STATUS_UNRELIABLE:
				accuracyLabel.setText(R.string.accuracy_unreliable);
				break;
			case SensorManager.SENSOR_STATUS_ACCURACY_LOW:
				accuracyLabel.setText(R.string.accuracy_low);
				break;
			case SensorManager.SENSOR_STATUS_ACCURACY_MEDIUM:
				accuracyLabel.setText(R.string.accuracy_medium);
				break;
			case SensorManager.SENSOR_STATUS_ACCURACY_HIGH:
				accuracyLabel.setText(R.string.accuracy_high);
				break;
			}
		}
	}
 
	public void onSensorChanged(SensorEvent event) {
		int sensorType = event.sensor.getType();
		if (sensorType == Sensor.TYPE_ACCELEROMETER) {
			a = event.values;
			accel = (float) (Math.sqrt((a[0]*a[0]+a[1]*a[1]+a[2]*a[2]))-SensorManager.GRAVITY_EARTH)-accelDiff;
			curAccel += accel;
			accelUpdates++;
 
			long curTime = event.timestamp - lastUpdate;
			if (curTime > 1000000000) {
				curAccel = curAccel/accelUpdates;
				speed += curAccel*curTime*10e-10;
				moved += speed*curTime*10e-10;
 
				lastUpdate = event.timestamp;
 
				xLabel.setText(String.format("Moved: %+2.20f", moved));
				yLabel.setText(String.format("Speed: %+2.20f", speed));
				zLabel.setText(String.format("Accel: %+2.20f Time:  %+2.3f", curAccel, curTime*10e-10));
				curAccel = 0;
				accelUpdates = 0;
			}
		}
	}
}