判断Android机器是否在充电

package com.android.factorymode;

import android.app.Activity;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.BatteryManager;
import android.os.Bundle;
import android.widget.TextView;

public class ChargeTest extends Activity
{
    TextView myText;
    private BroadcastReceiver mbatteryReceiver=new BroadcastReceiver()
    {
        public void onReceive(Context context, Intent intent)
        {
            String action =intent.getAction();
            if(Intent.ACTION_BATTERY_CHANGED.equals(action));
            {
                int status=intent.getIntExtra("status",BatteryManager.BATTERY_STATUS_UNKNOWN);
                if(status==BatteryManager.BATTERY_STATUS_CHARGING)
                {
                    myText.setText(R.string.Charge);
                }
                else
                {
                    myText.setText(R.string.notCharge);
                }
            }
        }
    };
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.charge_test);
        myText=(TextView)findViewById(R.id.message);

        registerReceiver(mbatteryReceiver, new IntentFilter(Intent.ACTION_BATTERY_CHANGED));
    }
}