InfoVerticalSpeed.java

/*******************************************************************************
 * Gaggle is Copyright 2010 by Geeksville Industries LLC, a California limited liability corporation. 
 * 
 * Gaggle is distributed under a dual license.  We've chosen this approach because within Gaggle we've used a number
 * of components that Geeksville Industries LLC might reuse for commercial products.  Gaggle can be distributed under
 * either of the two licenses listed below.
 * 
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; 
 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details. 
 * 
 * Commercial Distribution License
 * If you would like to distribute Gaggle (or portions thereof) under a license other than 
 * the "GNU General Public License, version 2", contact Geeksville Industries.  Geeksville Industries reserves
 * the right to release Gaggle source code under a commercial license of its choice.
 * 
 * GNU Public License, version 2
 * All other distribution of Gaggle must conform to the terms of the GNU Public License, version 2.  The full
 * text of this license is included in the Gaggle source, see assets/manual/gpl-2.0.txt.
 ******************************************************************************/
package com.geeksville.info;

import java.util.Observable;
import java.util.Observer;

import android.app.Activity;

import com.geeksville.gaggle.R;
import com.geeksville.location.BarometerClient;
import com.geeksville.location.IBarometerClient;

/**
 * A simple vario vertical speed display
 * 
 * @author kevinh
 * 
 */
public class InfoVerticalSpeed extends InfoField implements Observer {

  private float vspd = Float.NaN;

	private IBarometerClient baro;

  @Override
  public String getLabel() {
    return context.getString(R.string.vertical_speed);
  }

  /**
   * 
   * @see com.geeksville.info.InfoField#getLabel()
   */
  @Override
  public String getShortLabel() {
    return context.getString(R.string.vspd);
  }

  /**
   * 
   * @see com.geeksville.info.InfoField#getText()
   */
  @Override
  public String getText() {
    if (Float.isNaN(vspd))
      return "---";

    return Units.instance.meterPerSecToVSpeed(vspd);
  }

  /**
   * 
   * @see com.geeksville.info.InfoField#getUnits()
   */
  @Override
  public String getUnits() {
    // TODO Auto-generated method stub
    return Units.instance.getVSpeedUnits();
  }

  /**
   * @see com.geeksville.info.InfoField#onCreate(android.app.Activity)
   */
  @Override
  public void onCreate(Activity context) {
    super.onCreate(context);

    if (context != null) {
      // FIXME - we should share one compass client object
      baro = BarometerClient.create(context);
    }
  }

  /**
   * @see com.geeksville.info.InfoField#onHidden()
   */
  @Override
  void onHidden() {
    super.onHidden();

    if (baro != null)
      baro.deleteObserver(this);
  }

  /**
   * @see com.geeksville.info.InfoField#onShown()
   */
  @Override
  void onShown() {
    super.onShown();

    if (baro != null)
      baro.addObserver(this);
  }

  @Override
  public void update(Observable observable, Object data) {

    float nvspd = baro.getVerticalSpeed();

    if (nvspd != vspd) {
      vspd = nvspd;

      onChanged();
    }
  }

}