Replay for Preact: Lightweight UI Generation from Video

TL;DR: Replay revolutionizes Preact development by generating lightweight, functional UI components directly from video recordings, enabling faster prototyping and behavior-driven development.

Stop building UI the hard way. You're staring at a finished product in a demo video, a user flow recording, or a competitor's site. Why are you still manually transcribing pixels and interactions into code? Screenshot-to-code is a dead end – it only captures static visuals. You need to understand the behavior to truly replicate the experience. That's where Replay comes in.

Replay: Behavior-Driven Reconstruction for Preact#

Replay is a game-changer. It's a video-to-code engine powered by Gemini that reconstructs working UI, specifically targeting Preact's lightweight and performant nature. Replay uses "Behavior-Driven Reconstruction" – analyzing video as the source of truth, understanding user intent, and generating functional Preact components. Forget pixel-perfect recreations; Replay delivers functional equivalents.

Why Preact?#

Preact's small size and API compatibility with React make it ideal for rapid prototyping and performance-critical applications. Replay leverages these strengths by generating highly optimized Preact code.

The Problem with Screenshot-to-Code#

Screenshot-to-code tools are fundamentally limited. They only capture a static snapshot of the UI. They don't understand:

• •User interactions (clicks, scrolls, form submissions)
• •Dynamic state changes
• •Underlying logic

This results in code that is often incomplete, brittle, and requires significant manual rework. Replay, on the other hand, analyzes the entire video to understand the user's journey and the application's behavior.

Replay vs. the Competition#

Key Features of Replay for Preact#

• •Multi-page Generation: Replay understands navigation and can generate code for entire product flows, not just single pages.
• •Supabase Integration: Seamlessly connect your Replay-generated Preact components to your Supabase backend.
• •Style Injection: Replay intelligently infers and applies styling based on the video, creating visually consistent components.
• •Product Flow Maps: Visualize the user journey extracted from the video, providing a clear understanding of the application's structure.

Building a Preact Component with Replay: A Step-by-Step Guide#

Let's say you have a video recording of a user interacting with a simple to-do list application. You want to recreate this in Preact using Replay.

Step 1: Upload the Video to Replay#

Simply upload your video recording to the Replay platform. Replay supports various video formats and resolutions.

Step 2: Replay Analyzes the Video#

Replay's AI engine analyzes the video, identifying UI elements, user interactions, and state changes. This process typically takes a few minutes, depending on the length of the video.

Step 3: Review and Refine the Generated Code#

Replay generates Preact code that closely mirrors the functionality demonstrated in the video. You can review and refine the code directly within the Replay interface.

Step 4: Download and Integrate the Preact Component#

Download the generated Preact component and integrate it into your existing Preact project.

Example: A Simple To-Do List Component#

Here's an example of Preact code that Replay might generate from a video of a to-do list application:

typescript
// Preact component generated by Replay
import { h, useState } from 'preact';

const TodoList = () => {
  const [todos, setTodos] = useState<string[]>([]);
  const [newTodo, setNewTodo] = useState('');

  const addTodo = () => {
    if (newTodo.trim() !== '') {
      setTodos([...todos, newTodo.trim()]);
      setNewTodo('');
    }
  };

  const removeTodo = (index: number) => {
    const newTodos = [...todos];
    newTodos.splice(index, 1);
    setTodos(newTodos);
  };

  return (
    <div>
      <input
        type="text"
        value={newTodo}
        onChange={(e) => setNewTodo(e.target.value)}
        placeholder="Add a new todo"
      />
      <button onClick={addTodo}>Add</button>
      <ul>
        {todos.map((todo, index) => (
          <li key={index}>
            {todo}
            <button onClick={() => removeTodo(index)}>Remove</button>
          </li>
        ))}
      </ul>
    </div>
  );
};

export default TodoList;

💡 Pro Tip: Replay's style injection feature can automatically generate CSS or styled-components code to match the visual appearance of the video.

Connecting to Supabase#

Replay simplifies connecting your Preact components to a Supabase backend. You can configure Replay to automatically generate the necessary API calls and data bindings.

typescript
// Example of fetching data from Supabase using Replay-generated code
import { useEffect, useState } from 'preact/hooks';
import { createClient } from '@supabase/supabase-js';

const supabaseUrl = 'YOUR_SUPABASE_URL';
const supabaseKey = 'YOUR_SUPABASE_ANON_KEY';
const supabase = createClient(supabaseUrl, supabaseKey);

const MyComponent = () => {
  const [data, setData] = useState([]);

  useEffect(() => {
    const fetchData = async () => {
      const { data, error } = await supabase
        .from('your_table')
        .select('*');

      if (error) {
        console.error('Error fetching data:', error);
      } else {
        setData(data);
      }
    };

    fetchData();
  }, []);

  return (
    <ul>
      {data.map(item => (
        <li key={item.id}>{item.name}</li>
      ))}
    </ul>
  );
};

export default MyComponent;

📝 Note: You'll need to replace

text

YOUR_SUPABASE_URL

and

text

YOUR_SUPABASE_ANON_KEY

with your actual Supabase credentials.

Benefits of Using Replay for Preact#

• •Rapid Prototyping: Quickly generate functional Preact components from video recordings, accelerating the prototyping process.
• •Improved Accuracy: Replay's behavior-driven approach ensures that the generated code accurately reflects the intended functionality.
• •Reduced Manual Effort: Automate the tedious task of manually transcribing UI designs into code.
• •Enhanced Collaboration: Share video recordings and Replay-generated code with your team for seamless collaboration.

⚠️ Warning: While Replay significantly reduces development time, it's important to review and test the generated code thoroughly.

Frequently Asked Questions#

Is Replay free to use?#

Replay offers a free tier with limited functionality. Paid plans are available for more advanced features and usage. Check the pricing page for more details.

How is Replay different from v0.dev?#

v0.dev generates UI components based on text prompts. Replay analyzes video of existing UIs, enabling it to capture nuanced behavior and generate more accurate and functional code. Replay focuses on behavior-driven reconstruction, whereas v0.dev relies on prompt engineering.

What video formats are supported?#

Replay supports most common video formats, including MP4, MOV, and WebM.

Can I use Replay to generate code for complex UIs?#

Yes, Replay is capable of generating code for complex UIs with multiple pages and interactions. The quality of the generated code depends on the clarity and completeness of the video recording.

Does Replay support custom styling?#

Yes, Replay includes style injection capabilities, allowing you to customize the appearance of the generated components. You can also manually edit the CSS or styled-components code.

How secure is my video data?#

Replay prioritizes data security. All video uploads are encrypted and stored securely. You can delete your videos at any time.

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Ready to try behavior-driven code generation? Get started with Replay - transform any video into working code in seconds.