Android 检测网络是否可用

/**
	 * 检测网络是否可用
	 * @return
	 */
	public boolean isNetworkConnected() {
		ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
		NetworkInfo ni = cm.getActiveNetworkInfo();
		return ni != null && ni.isConnectedOrConnecting();
	}