DoubleClickExitHelper.java

package com.iwhys.cnode.util;

import android.app.Activity;
import android.os.Handler;
import android.os.Looper;
import android.view.KeyEvent;
import android.widget.Toast;

/**
 * 类名 DoubleClickExitHelper.java</br>
 * 创建日期 2014年4月28日</br>
 * @author LeonLee (http://my.oschina.net/lendylongli)</br>
 * Email lendylongli@gmail.com</br>
 * 更新时间 2014年4月28日 上午12:14:06</br>
 * 最后更新者 LeonLee</br>
 * 
 * 说明 双击退出
 */
public class DoubleClickExitHelper {

	private final Activity mActivity;
	
	private boolean isOnKeyBacking;
	private Handler mHandler;
	private Toast mBackToast;
	
	public DoubleClickExitHelper(Activity activity) {
		mActivity = activity;
		mHandler = new Handler(Looper.getMainLooper());
	}
	
	/**
	 * Activity onKeyDown事件
	 * */
	public boolean onKeyDown(int keyCode, KeyEvent event) {
		if(keyCode != KeyEvent.KEYCODE_BACK) {
			return false;
		}
		if(isOnKeyBacking) {
			mHandler.removeCallbacks(onBackTimeRunnable);
			if(mBackToast != null){
				mBackToast.cancel();
			}
            //退出程序
            ActivitySwitcher.popDefault(mActivity);
			return true;
		} else {
			isOnKeyBacking = true;
			if(mBackToast == null) {
				mBackToast = Toast.makeText(mActivity, "再按一次退出！", Toast.LENGTH_LONG);
			}
			mBackToast.show();
			mHandler.postDelayed(onBackTimeRunnable, 3000);
			return true;
		}
	}
	
	private Runnable onBackTimeRunnable = new Runnable() {
		
		@Override
		public void run() {
			isOnKeyBacking = false;
			if(mBackToast != null){
				mBackToast.cancel();
			}
		}
	};
}