Android 判断程序是否在前台运行

protected static boolean isTopActivity(Activity activity) {
		String packageName = "com.liujy.android.test";
		ActivityManager activityManager = (ActivityManager) activity
				.getSystemService(Context.ACTIVITY_SERVICE);
		List<RunningTaskInfo> tasksInfo = activityManager.getRunningTasks(1);
		if (tasksInfo.size() > 0) {
			// 应用程序位于堆栈的顶层
			if (packageName.equals(tasksInfo.get(0).topActivity.getPackageName())) {
				return true;
			}
		}
		return false;
	}