Android监听Home键和Back键的区别介绍

package com.scd.homewatcher.util;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.util.Log;

/**
 * Home键监听封装
 * 
 * @author way
 * 
 */
public class HomeWatcher {

  // 回调接口
  public interface OnHomePressedListener {

    public void onHomePressed();

    public void onHomeLongPressed();
  }

  private static final String TAG = "HomeWatcher";
  /** 上下文 */
  private Context mContext;
  /** 过滤器 */
  private IntentFilter mFilter;
  /** 接口 */
  private OnHomePressedListener mListener;
  /** 广播接收者 */
  private InnerRecevier mRecevier;

  public HomeWatcher(Context context) {
    mContext = context;
    mRecevier = new InnerRecevier();
    mFilter = new IntentFilter(Intent.ACTION_CLOSE_SYSTEM_DIALOGS);
  }

  /**
   * 设置监听
   * 
   * @param listener
   */
  public void setOnHomePressedListener(OnHomePressedListener listener) {
    mListener = listener;
  }

  /**
   * 开始监听，注册广播
   */
  public void startWatch() {
    if (mRecevier != null) {
      mContext.registerReceiver(mRecevier, mFilter);
    }
  }

  /**
   * 停止监听，注销广播
   */
  public void stopWatch() {
    if (mRecevier != null) {
      mContext.unregisterReceiver(mRecevier);
    }
  }

  /**
   * 广播接收者
   */
  private class InnerRecevier extends BroadcastReceiver {
    final String SYSTEM_DIALOG_REASON_KEY = "reason";
    final String SYSTEM_DIALOG_REASON_GLOBAL_ACTIONS = "globalactions";
    final String SYSTEM_DIALOG_REASON_RECENT_APPS = "recentapps";
    final String SYSTEM_DIALOG_REASON_HOME_KEY = "homekey";

    @Override
    public void onReceive(Context context, Intent intent) {
      String action = intent.getAction();
      if (action.equals(Intent.ACTION_CLOSE_SYSTEM_DIALOGS)) {
        String reason = intent.getStringExtra(SYSTEM_DIALOG_REASON_KEY);
        if (reason != null) {
          Log.i(TAG, "action:" + action + ",reason:" + reason);
          if (mListener != null) {
            if (reason.equals(SYSTEM_DIALOG_REASON_HOME_KEY)) {
              // 短按home键
              mListener.onHomePressed();
            } else if (reason
                .equals(SYSTEM_DIALOG_REASON_RECENT_APPS)) {
              // 长按home键
              mListener.onHomeLongPressed();
            }
          }
        }
      }
    }
  }
}

package com.scd.homewatcher;

import android.app.Activity;
import android.os.Bundle;
import android.view.KeyEvent;
import android.widget.Toast;

import com.scd.homewatcher.util.HomeWatcher;
import com.scd.homewatcher.util.HomeWatcher.OnHomePressedListener;

public class MainActivity extends Activity implements OnHomePressedListener {
  private HomeWatcher mHomeWatcher;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

  }

  @Override
  protected void onResume() {
    mHomeWatcher = new HomeWatcher(this);
    mHomeWatcher.setOnHomePressedListener(this);
    // 注册广播
    mHomeWatcher.startWatch();
    super.onResume();
  }

  @Override
  protected void onPause() {
    mHomeWatcher.setOnHomePressedListener(null);
    // 注销广播
    mHomeWatcher.stopWatch();
    super.onPause();
  }

  @Override
  public void onHomePressed() {
    // TODO
    Toast.makeText(this, "短按Home键,实现自己的逻辑", Toast.LENGTH_SHORT).show();

  }

  @Override
  public void onHomeLongPressed() {
    // TODO
    Toast.makeText(this, "长按Home键,实现自己的逻辑", Toast.LENGTH_SHORT).show();

  }

  @Override
  public boolean onKeyDown(int keyCode, KeyEvent event) {
    if ((keyCode == KeyEvent.KEYCODE_BACK)) {
      System.out.println("按下了back键 onKeyDown()");
      return false;
    } else {
      return super.onKeyDown(keyCode, event);
    }

  }

  @Override
  public void onBackPressed() {
    // super.onBackPressed()会自动调用finish()方法,关闭
    super.onBackPressed();
  }

}