增加若干基础页面

lib/utils/tool.dart

@@ -1,9 +1,45 @@
+import 'dart:io';
+
+import 'package:bot_toast/bot_toast.dart';
+import 'package:flutter/material.dart';
+
 class ToolFn {
+  DateTime? lastPressedAt; //上次点击时间
+
   // 字符串是否为空
-  static bool isBlank(String? str) {
-    if (str == null || str.isEmpty) {
+  static bool isBlank(String str) {
+    if (str.isEmpty) {
       return true;
     }
     return false;
   }
+
+  ///手机号验证(只验证前三位号段)
+  static bool checkMobile(String str) {
+    if (isBlank(str)) {
+      return true;
+    }
+    return !RegExp(r"^1(3\d|4[5-9]|5[0-35-9]|6[567]|7[0-8]|8\d|9[0-35-9])\d{8}")
+        .hasMatch(str);
+  }
+
+  static void tips(String msg) {
+    BotToast.showText(
+        text: msg,
+        contentColor: Colors.black,
+        textStyle: const TextStyle(fontSize: 17, color: Colors.white));
+  }
+
+  // 监听返回键
+  void isExit() {
+    if (lastPressedAt == null ||
+        DateTime.now().difference(lastPressedAt!) >
+            const Duration(seconds: 1)) {
+      //两次点击间隔超过1秒则重新计时
+      lastPressedAt = DateTime.now();
+      ToolFn.tips("再按一次退出程序");
+      return;
+    }
+    exit(0);
+  }
 }