GPSButton.java

package com.android.settings.widget.buttons;

import android.content.ContentResolver;
import android.content.Context;
import android.content.SharedPreferences;
import android.location.LocationManager;
import android.provider.Settings;

import com.android.settings.R;
import com.android.settings.widget.SettingsAppWidgetProvider;
import com.android.settings.widget.WidgetSettings;

public class GPSButton extends WidgetButton {

	static GPSButton ownButton=null;

	public void updateState(Context context,
			SharedPreferences globalPreferences, int[] appWidgetIds) {
		if (getGpsState(context)) {
			currentIcon=R.drawable.ic_appwidget_settings_gps_on;
			currentState=SettingsAppWidgetProvider.STATE_ENABLED;
		} else {
			currentIcon=R.drawable.ic_appwidget_settings_gps_off;
			currentState=SettingsAppWidgetProvider.STATE_DISABLED;
		}		

	}

	/**
	 * Toggles the state of GPS.
	 * 
	 * @param context
	 */
	public void toggleState(Context context) {
		ContentResolver resolver = context.getContentResolver();
		boolean enabled = getGpsState(context);
		Settings.Secure.setLocationProviderEnabled(resolver,
				LocationManager.GPS_PROVIDER, !enabled);
	}	

	/**
	 * Gets the state of GPS location.
	 * 
	 * @param context
	 * @return true if enabled.
	 */
	private static boolean getGpsState(Context context) {
		ContentResolver resolver = context.getContentResolver();
		return Settings.Secure.isLocationProviderEnabled(resolver,
				LocationManager.GPS_PROVIDER);
	}


	public static GPSButton getInstance() {
		if (ownButton==null)
			ownButton = new GPSButton();

		return ownButton;
	}

	@Override
	void initButton() {
		buttonID=WidgetButton.BUTTON_GPS;
		preferenceName=WidgetSettings.TOGGLE_GPS;
	}

}