Simply implement snippet running.

lib/view/page/snippet/edit.dart

@@ -1,15 +1,91 @@
+import 'package:after_layout/after_layout.dart';
 import 'package:flutter/material.dart';
+import 'package:toolbox/core/utils.dart';
+import 'package:toolbox/data/model/server/snippet.dart';
+import 'package:toolbox/data/provider/snippet.dart';
+import 'package:toolbox/locator.dart';
+import 'package:toolbox/view/widget/input_decoration.dart';
 
 class SnippetEditPage extends StatefulWidget {
-  const SnippetEditPage({Key? key}) : super(key: key);
+  const SnippetEditPage({Key? key, this.snippet}) : super(key: key);
+
+  final Snippet? snippet;
 
   @override
   _SnippetEditPageState createState() => _SnippetEditPageState();
 }
 
-class _SnippetEditPageState extends State<SnippetEditPage> {
+class _SnippetEditPageState extends State<SnippetEditPage>
+    with AfterLayoutMixin {
+  final nameController = TextEditingController();
+  final scriptController = TextEditingController();
+
+  late SnippetProvider _provider;
+
+  @override
+  void initState() {
+    super.initState();
+    _provider = locator<SnippetProvider>();
+  }
+
   @override
   Widget build(BuildContext context) {
-    return Scaffold(appBar: AppBar(title: const Text('Snippet Edit'),), body: const Center(child: Text('Developing'),),);
+    return Scaffold(
+      appBar: AppBar(title: const Text('Edit'), actions: [
+        widget.snippet != null
+            ? IconButton(
+                onPressed: () {
+                  _provider.delInfo(widget.snippet!);
+                  Navigator.of(context).pop();
+                },
+                icon: const Icon(Icons.delete))
+            : const SizedBox()
+      ]),
+      body: ListView(
+        padding: const EdgeInsets.all(13),
+        children: [
+          TextField(
+            controller: nameController,
+            keyboardType: TextInputType.text,
+            decoration: buildDecoration('Name', icon: Icons.info),
+          ),
+          TextField(
+            controller: scriptController,
+            autocorrect: false,
+            minLines: 3,
+            maxLines: 10,
+            keyboardType: TextInputType.text,
+            enableSuggestions: false,
+            decoration: buildDecoration('Snippet', icon: Icons.code),
+          ),
+        ],
+      ),
+      floatingActionButton: FloatingActionButton(
+        child: const Icon(Icons.send),
+        onPressed: () {
+          final name = nameController.text;
+          final script = scriptController.text;
+          if (name.isEmpty || script.isEmpty) {
+            showSnackBar(context, const Text('Two fields must not be empty.'));
+            return;
+          }
+          final snippet = Snippet(name, script);
+          if (widget.snippet != null) {
+            _provider.updateInfo(widget.snippet!, snippet);
+          } else {
+            _provider.addInfo(snippet);
+          }
+          Navigator.of(context).pop();
+        },
+      ),
+    );
+  }
+
+  @override
+  void afterFirstLayout(BuildContext context) {
+    if (widget.snippet != null) {
+      nameController.text = widget.snippet!.name;
+      scriptController.text = widget.snippet!.script;
+    }
   }
 }