Update README.md

Author: JarvanMo

README.md

@@ -4,4 +4,125 @@
 
 ## Getting Started
 
-For help getting started with Flutter, view our on
+For help getting started with Flutter, view our online [documentation](https://flutter.io/).
+
+For help on editing package code, view the [documentation](https://flutter.io/developing-packages/).
+![image](https://github.com/zhangruiyu/flutter_gesture_password/blob/master/wow.gif)
+
+## How to use ?
+
+1. Depend on it
+ 
+```yaml
+dependencies:
+  gesture_password: "^0.0.4"
+```
+
+2. Install it
+ 
+```sh
+$ flutter packages get
+```
+
+3. Import it
+
+```dart
+import 'package:gesture_password/gesture_password.dart';
+import 'package:gesture_password/mini_gesture_password.dart';
+```
+
+## 属性
+* width 控件宽度(xia-weiyang想法)
+* selectedColor 选中的颜色
+* normalColor:  没选中的颜色
+* lineStrokeWidth: 线宽
+* circleStrokeWidth: 选中外圈圆宽
+* smallCircleR: 小圆半径
+* bigCircleR: 大圆半径
+* focusDistance: 选中差值 越大越容易选中
+* successCallback 选择4个以上松手回调,返回值为选中的index相加的字符串
+* failCallback 选择4下以上松手回调
+* selectedCallback 经过任意一个后回调,返回值为选中的index相加的字符串
+
+## Example
+```
+import 'package:flutter/material.dart';
+import 'package:gesture_password/gesture_password.dart';
+import 'package:gesture_password/mini_gesture_password.dart';
+
+void main() => runApp(new MyApp());
+
+class MyApp extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    return new MaterialApp(
+      title: 'Flutter Demo',
+      theme: new ThemeData(
+        primarySwatch: Colors.blue,
+      ),
+      home: new MyHomePage(title: 'Flutter Demo Home Page'),
+    );
+  }
+}
+
+class MyHomePage extends StatefulWidget {
+  MyHomePage({Key key, this.title}) : super(key: key);
+
+  final String title;
+
+  @override
+  _MyHomePageState createState() => new _MyHomePageState();
+}
+
+class _MyHomePageState extends State<MyHomePage> {
+  GlobalKey<MiniGesturePasswordState> miniGesturePassword =
+      new GlobalKey<MiniGesturePasswordState>();
+
+  GlobalKey<ScaffoldState> scaffoldState = new GlobalKey<ScaffoldState>();
+
+  @override
+  Widget build(BuildContext context) {
+    return new MaterialApp(
+      home: new Scaffold(
+        key: scaffoldState,
+        appBar: new AppBar(
+          title: new Text('Plugin example app'),
+        ),
+        body: new Column(
+          children: <Widget>[
+            new Center(
+                child: new MiniGesturePassword(key: miniGesturePassword)),
+            new LayoutBuilder(
+              builder: (BuildContext context, BoxConstraints constraints) {
+                return new Container(
+                  color: Colors.red,
+                  margin: const EdgeInsets.only(top: 100.0),
+                  child: new GesturePassword(
+                    successCallback: (s) {
+                      print("successCallback$s");
+                      scaffoldState.currentState?.showSnackBar(new SnackBar(
+                          content: new Text('successCallback:$s')));
+                      miniGesturePassword.currentState?.setSelected('');
+                    },
+                    failCallback: () {
+                      print('failCallback');
+                      scaffoldState.currentState?.showSnackBar(
+                          new SnackBar(content: new Text('failCallback')));
+                      miniGesturePassword.currentState?.setSelected('');
+                    },
+                    selectedCallback: (str) {
+                      miniGesturePassword.currentState?.setSelected(str);
+                    },
+                  ),
+                );
+              },
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}
+```
+
+##### 有需求的话,后期再加入其他的吧