SvelteKit UI Prototyping: From Screen Recording to Interactive App

TL;DR: Replay lets you rapidly prototype SvelteKit UIs by converting screen recordings of user flows into functional code, saving you time and effort compared to traditional methods.

SvelteKit UI Prototyping: From Screen Recording to Interactive App#

Building user interfaces can be time-consuming, especially in the early stages of prototyping. You often find yourself writing boilerplate code and tweaking designs before even validating your core ideas. What if you could skip the initial setup and jump straight into a functional prototype based on a simple screen recording?

That's where Replay comes in. Replay is a video-to-code engine that uses Gemini to understand user behavior and reconstruct working UI from screen recordings. Forget static mockups; Replay delivers interactive SvelteKit components ready for further development.

The Problem with Traditional Prototyping#

Traditional UI prototyping often involves these steps:

1. •Design Mockups: Creating static designs in tools like Figma or Sketch.
2. •Manual Coding: Translating those designs into code, which is often tedious and repetitive.
3. •Iteration: Making changes based on feedback, which requires going back to the design and recoding.

This process can be slow and inefficient, especially when you're exploring different ideas or trying to validate a user flow quickly. Screenshot-to-code tools offer a partial solution, but they lack the crucial understanding of user intent. They just see pixels, not actions.

Replay: Behavior-Driven Reconstruction#

Replay takes a different approach. Instead of relying on static screenshots, it analyzes video recordings of user interactions. This allows Replay to understand the behavior behind the UI, leading to more accurate and functional code generation.

Here's how Replay works:

1. •Record: Capture a screen recording of your desired user flow. This could be a demonstration of how a user interacts with an existing website or a hand-drawn mockup brought to life.
2. •Upload: Upload the video to Replay.
3. •Generate: Replay analyzes the video, identifies UI elements, and reconstructs the corresponding SvelteKit components.
4. •Customize: Fine-tune the generated code and integrate it into your SvelteKit project.

Key Features of Replay#

• •Multi-page Generation: Replay can handle complex user flows that span multiple pages.
• •Supabase Integration: Easily connect your generated UI to a Supabase backend.
• •Style Injection: Replay intelligently infers and applies styles based on the video.
• •Product Flow Maps: Visualize the user flow that Replay has identified.

Replay vs. Screenshot-to-Code Tools#

Here's a comparison of Replay with traditional screenshot-to-code tools:

Building a SvelteKit UI with Replay: A Step-by-Step Guide#

Let's walk through an example of using Replay to prototype a simple SvelteKit UI. We'll create a basic task list application.

Step 1: Recording the User Flow

First, record a video of yourself interacting with a hand-drawn mockup or a simple HTML prototype of the task list. Demonstrate the following actions:

1. •Adding a new task.
2. •Marking a task as complete.
3. •Deleting a task.

The clearer the video, the better Replay can understand the user flow.

Step 2: Uploading to Replay

Upload the recorded video to the Replay platform. The platform will process the video and begin the code generation process.

Step 3: Reviewing and Customizing the Generated Code

Once Replay has finished processing the video, you'll be presented with the generated SvelteKit code. This will include:

• •Svelte components for the task list and individual tasks.
• •JavaScript code for handling user interactions.
• •CSS styles for the UI elements.

svelte
<!-- src/lib/components/TaskList.svelte -->
<script>
  let tasks = [
    { id: 1, text: 'Learn SvelteKit', completed: false },
    { id: 2, text: 'Build a Replay prototype', completed: true },
  ];

  let newTask = '';

  function addTask() {
    if (newTask) {
      tasks = [...tasks, { id: Date.now(), text: newTask, completed: false }];
      newTask = '';
    }
  }

  function toggleComplete(id) {
    tasks = tasks.map(task =>
      task.id === id ? { ...task, completed: !task.completed } : task
    );
  }

  function deleteTask(id) {
    tasks = tasks.filter(task => task.id !== id);
  }
</script>

<div class="task-list">
  <h1>Task List</h1>
  <div class="add-task">
    <input type="text" bind:value={newTask} placeholder="Add a new task" />
    <button on:click={addTask}>Add</button>
  </div>
  <ul>
    {#each tasks as task (task.id)}
      <li class:completed={task.completed}>
        <input type="checkbox" checked={task.completed} on:change={() => toggleComplete(task.id)} />
        <span>{task.text}</span>
        <button on:click={() => deleteTask(task.id)}>Delete</button>
      </li>
    {/each}
  </ul>
</div>

<style>
  .task-list {
    font-family: sans-serif;
  }

  .add-task {
    margin-bottom: 1rem;
  }

  .completed {
    text-decoration: line-through;
    color: gray;
  }
</style>

Review the generated code and make any necessary adjustments. You might need to refine the styles or add more complex logic.

Step 4: Integrating with Supabase (Optional)

If you want to persist the task list data, you can easily integrate Replay with Supabase. Replay can generate the necessary code to connect to your Supabase database and perform CRUD operations on the task list.

typescript
// src/lib/supabaseClient.js
import { createClient } from '@supabase/supabase-js'

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

svelte
// src/lib/components/TaskList.svelte (with Supabase)
<script>
  import { supabase } from '../supabaseClient';
  import { onMount } from 'svelte';

  let tasks = [];
  let newTask = '';

  onMount(async () => {
    await fetchTasks();
  });

  async function fetchTasks() {
    const { data, error } = await supabase
      .from('tasks')
      .select('*')
      .order('id', { ascending: false });

    if (error) {
      console.error('Error fetching tasks:', error);
      return;
    }

    tasks = data;
  }

  async function addTask() {
    if (newTask) {
      const { data, error } = await supabase
        .from('tasks')
        .insert([{ text: newTask, completed: false }])
        .select();

      if (error) {
        console.error('Error adding task:', error);
        return;
      }

      tasks = [...tasks, data[0]]; // Assuming data is returned correctly
      newTask = '';
      await fetchTasks(); // Refresh tasks after adding
    }
  }

  async function toggleComplete(id, completed) {
    const { error } = await supabase
      .from('tasks')
      .update({ completed: !completed })
      .eq('id', id);

    if (error) {
      console.error('Error updating task:', error);
      return;
    }
    await fetchTasks(); // Refresh tasks after updating
  }

  async function deleteTask(id) {
    const { error } = await supabase
      .from('tasks')
      .delete()
      .eq('id', id);

    if (error) {
      console.error('Error deleting task:', error);
      return;
    }
    await fetchTasks(); // Refresh tasks after deleting
  }
</script>

<!-- Rest of the component remains similar, using the functions above -->

💡 Pro Tip: For more complex UIs, break down the recording into smaller, more focused videos. This will help Replay generate more accurate and maintainable code.

📝 Note: Replay is constantly improving its code generation capabilities. Be sure to check the documentation for the latest features and best practices.

Benefits of Using Replay for SvelteKit Prototyping#

• •Rapid Prototyping: Quickly generate functional UI prototypes from screen recordings.
• •Reduced Boilerplate: Eliminate the need to write repetitive boilerplate code.
• •Improved Collaboration: Easily share prototypes with stakeholders for feedback.
• •Behavior-Driven Development: Focus on user behavior and intent, leading to more user-friendly UIs.
• •Faster Iteration: Quickly iterate on prototypes based on user feedback.

⚠️ Warning: While Replay significantly accelerates the prototyping process, it's crucial to review and refine the generated code. Treat it as a starting point for further development.

Real-World Use Cases#

Replay can be used in a variety of scenarios, including:

• •Validating UI/UX concepts: Quickly create prototypes to test different UI ideas.
• •Building MVPs: Develop a minimum viable product faster than with traditional methods.
• •Creating interactive tutorials: Generate code examples from screen recordings of software usage.
• •Reverse engineering existing UIs: Reconstruct the code behind a UI by recording a video of its usage.

Beyond Simple Prototypes#

Replay's capabilities extend beyond simple prototypes. With its ability to understand user flows and generate complex UI components, it can be used to build entire applications. The integration with Supabase allows for seamless backend connectivity, making it a powerful tool for full-stack development.

Frequently Asked Questions#

Is Replay free to use?#

Replay offers a free tier with limited features. Paid plans are available for more advanced features and usage. Check the pricing page for the most up-to-date information.

How is Replay different from v0.dev?#

While both tools aim to accelerate UI development, Replay focuses on behavior-driven reconstruction from video, whereas v0.dev relies on AI-powered code generation from text prompts. Replay excels at capturing existing UI patterns and user flows, while v0.dev is better suited for generating novel UI designs.

What types of videos work best with Replay?#

Clear, well-lit videos with minimal background noise tend to produce the best results. Focus on demonstrating the desired user flow clearly and concisely.

What SvelteKit features are supported by Replay?#

Replay supports a wide range of SvelteKit features, including components, routes, stores, and actions. It is constantly being updated to support the latest SvelteKit features.

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