小编use*_*291的帖子

我写的是非常简单的应用程序.它工作正常,但是当我按下后退键时它崩溃了(Activity已经泄露了最初在这里注册的IntentReceiver).这个应用程序应该在后台工作.怎么做得好？

import android.app.Activity;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.SharedPreferences;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.os.PowerManager;
import android.os.PowerManager.WakeLock;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ProgressBar;
import android.widget.RadioButton;
import android.widget.SeekBar;
import android.widget.SeekBar.OnSeekBarChangeListener;
import android.widget.TextView;
import android.widget.Toast;

public class Bateria extends Activity implements OnClickListener, OnSeekBarChangeListener {

    ProgressBar pbBatteryLevel;
    TextView tvBatteryLevel;
    TextView tvLeft;
    RadioButton rbPercent;
    RadioButton rbTime;
    SeekBar sbSetLeft;
    boolean percent; // true - percent, false - time
    boolean informed;
    int progress;
    int MAX_TIME;

    /** …