BluetoothButton.java

package com.android.settings.widget.buttons;

import com.android.settings.R;
import com.android.settings.bluetooth.LocalBluetoothManager;
import com.android.settings.widget.SettingsAppWidgetProvider;
import com.android.settings.widget.StateTracker;
import com.android.settings.widget.WidgetSettings;

import android.bluetooth.BluetoothAdapter;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.AsyncTask;
import android.util.Log;

public class BluetoothButton extends WidgetButton{

	private static LocalBluetoothManager sLocalBluetoothManager = null;

	private static final StateTracker sBluetoothState = new BluetoothStateTracker();

	static BluetoothButton ownButton=null;


	/**
	 * Subclass of StateTracker to get/set Bluetooth state.
	 */
	private static final class BluetoothStateTracker extends StateTracker {

		@Override
		public int getActualState(Context context) {
			if (sLocalBluetoothManager == null) {
				sLocalBluetoothManager = LocalBluetoothManager
				.getInstance(context);
				if (sLocalBluetoothManager == null) {
					return SettingsAppWidgetProvider.STATE_UNKNOWN; // On emulator?
				}
			}
			return bluetoothStateToFiveState(sLocalBluetoothManager
					.getBluetoothState());
		}

		@Override
		protected void requestStateChange(Context context,
				final boolean desiredState) {
			if (sLocalBluetoothManager == null) {
				Log.d(SettingsAppWidgetProvider.TAG, "No LocalBluetoothManager");
				return;
			}
			// Actually request the Bluetooth change and persistent
			// settings write off the UI thread, as it can take a
			// user-noticeable amount of time, especially if there's
			// disk contention.
			new AsyncTask<Void, Void, Void>() {
				@Override
				protected Void doInBackground(Void... args) {
					sLocalBluetoothManager.setBluetoothEnabled(desiredState);
					return null;
				}
			}.execute();
		}

		@Override
		public void onActualStateChange(Context context, Intent intent) {
			if (!BluetoothAdapter.ACTION_STATE_CHANGED.equals(intent
					.getAction())) {
				return;
			}
			int bluetoothState = intent.getIntExtra(
					BluetoothAdapter.EXTRA_STATE, -1);
			setCurrentState(context, bluetoothStateToFiveState(bluetoothState));
		}

		/**
		 * Converts BluetoothAdapter's state values into our
		 * Wifi/Bluetooth-common state values.
		 */
		private static int bluetoothStateToFiveState(int bluetoothState) {
			switch (bluetoothState) {
			case BluetoothAdapter.STATE_OFF:
				return SettingsAppWidgetProvider.STATE_DISABLED;
			case BluetoothAdapter.STATE_ON:
				return SettingsAppWidgetProvider.STATE_ENABLED;
			case BluetoothAdapter.STATE_TURNING_ON:
				return SettingsAppWidgetProvider.STATE_TURNING_ON;
			case BluetoothAdapter.STATE_TURNING_OFF:
				return SettingsAppWidgetProvider.STATE_TURNING_OFF;
			default:
				return SettingsAppWidgetProvider.STATE_UNKNOWN;
			}
		}
	}



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

		return ownButton;

	}    

	@Override
	void initButton() {
		buttonID=WidgetButton.BUTTON_BLUETOOTH;
		preferenceName=WidgetSettings.TOGGLE_BLUETOOTH;
	}

	@Override
	public void toggleState(Context context) {
		sBluetoothState.toggleState(context);
	}

	@Override
	public void updateState(Context context,
			SharedPreferences globalPreferences, int[] appWidgetIds) {
		currentState=sBluetoothState.getTriState(context);
		switch (currentState) {
		case SettingsAppWidgetProvider.STATE_DISABLED:
			currentIcon=R.drawable.ic_appwidget_settings_bluetooth_off;
			break;
		case SettingsAppWidgetProvider.STATE_ENABLED:
			currentIcon=R.drawable.ic_appwidget_settings_bluetooth_on;
			break;
		case SettingsAppWidgetProvider.STATE_INTERMEDIATE:
			// In the transitional state, the bottom green bar
			// shows the tri-state (on, off, transitioning), but
			// the top dark-gray-or-bright-white logo shows the
			// user's intent. This is much easier to see in
			// sunlight.
			if (sBluetoothState.isTurningOn()) {
				currentIcon=R.drawable.ic_appwidget_settings_bluetooth_on;
			} else {
				currentIcon=R.drawable.ic_appwidget_settings_bluetooth_off;
			}
			break;
		}
	}

	public void onReceive(Context context, Intent intent) {
		sBluetoothState.onActualStateChange(context, intent);		
	}

	public void toggleState(Context context, int newState) {
		int curState = sBluetoothState.getTriState(context);
		if (curState!= SettingsAppWidgetProvider.STATE_INTERMEDIATE &&
				curState!=newState) {
			toggleState(context);
		}
	}	
}