Flutter UI Builder - Visual Design Tool

I'll create a prototype of a Flutter UI Builder with a drag-and-drop interface, live code generation, and all the features you requested. Let's build a modern, intuitive UI that simulates how this tool would work.

Features Implemented

This Flutter UI Builder prototype includes all the core features you requested:

1. Drag-and-Drop UI Components

• Widget panel with categorized Flutter components
• Drag widgets onto the canvas
• Snapping guides for precise alignment (10px grid)
• Support for widget selection and positioning

2. Live Code Generation & Editing

• Real-time Dart code generation as you build the UI
• Code editor panel to view and edit the generated code
• Changes in the UI reflect in the code

3. Multi-Platform Preview

• Toggle between Android, iOS, Web, and Desktop views
• Canvas size adjusts based on the selected platform

4. Property Inspector Panel

• Edit widget properties like size, color, text, etc.
• Support for numeric inputs and visual controls
• Color picker for easy color selection

5. Component Hierarchy Panel

• Tree-view structure showing the widget hierarchy
• Select widgets from the hierarchy panel

6. Project Management & Export

• UI elements for saving, loading, and exporting projects
• Export projects as Flutter code

7. IDE Integration

• Button to open exported projects in Android Studio or VS Code

8. Custom Widget Support

• Framework in place to support custom widgets

9. Interactive Live Preview

• Click on widgets in the preview to edit properties instantly

How to Use

1. Add Widgets: Drag widgets from the left panel onto the canvas
2. Edit Properties: Select a widget and modify its properties in the right panel
3. View Hierarchy: Use the hierarchy panel to navigate complex UIs
4. Generate Code: The code panel automatically updates with Flutter Dart code
5. Change Platform: Switch between platforms using the dropdown in the top bar
6. Dark/Light Mode: Toggle between dark and light themes

This prototype demonstrates the UI and interaction flow of a Flutter UI Builder. In a production version, you would implement the actual Flutter rendering engine and more advanced features.

I'll fix the error with the TabsContent component not being properly nested within a Tabs component. The issue is in the code-panel.tsx file.

I've fixed the error by properly nesting the TabsContent components inside the Tabs component in the code-panel.tsx file.

The issue was that the TabsContent components were placed outside of the Tabs component, which violates the component structure required by the shadcn/ui tabs component. In the updated code:

1. I moved both TabsContent components inside the Tabs component
2. Maintained all the existing functionality
3. Kept the same styling and layout

This change ensures that the tabs will work correctly while preserving the original design and functionality of the code panel. The error "TabsContent must be used within Tabs" should now be resolved.