Update README.md

README.md

@@ -6,10 +6,34 @@ Usage
 Add this to your package's pubspec.yaml file:
 ``` yaml
 dependencies:
-  cool_ui: "^0.1.6"
+  cool_ui: "^0.0.7"
 ```
 
 ## CupertinoPopover
 仿iOS的UIPopover
 
-  
+![Image text](./images/popover_demo.gif)
+
+#### 案例核心代码
+```dart
+CupertinoPopoverButton(
+        child: Container(
+          margin: EdgeInsets.all(20.0),
+          width: 80.0,
+          height: 40.0,
+          decoration: BoxDecoration(
+              color: Colors.white,
+              borderRadius: BorderRadius.all(Radius.circular(5.0)),
+              boxShadow: [BoxShadow(color: Colors.black12,blurRadius: 5.0)]
+          ),
+          child: Center(child:Text('左上角')),
+        ),
+        popoverBody:Container(
+          width: 100.0,
+          height: 100.0,
+          child: Text('左上角内容'),
+        ),
+        popoverWidth: 100.0,
+        popoverHeight: 100.0);
+  }
+```