React Design Patterns in a Banking App

A showcase of real-world usage of essential React design patterns, applied in the context of a banking dashboard. This guide helps you learn not just the patterns, but exactly where and why they matter in production systems.

Table of Contents

• React Design Patterns in a Banking App
  • Table of Contents
  • 🔍 Design Patterns and Use Cases
    • 1. Container and Presentation
    • 2. Custom Hook Composition
    • 3. Reducer Pattern
    • 4. Provider Pattern
    • 5. Higher-Order Component (HOC)
    • 6. Compound Components
    • 7. Props Combination Pattern
    • 8. Controlled Component
    • 9. Error Boundary
    • 10. Forward Ref
    • 11. Lazy Loading
    • 12. Memoization
  • 🧪 Run It
  • 📚 Why It Matters
  • 🎥 Bonus: Tutorial Scripts (Coming Soon)
  • Feel free to contribute improvements or request a new pattern

🔍 Design Patterns and Use Cases

1. Container and Presentation

Use Case: Transaction history list

• TransactionContainer.tsx: Fetches and manages state
• TransactionList.tsx: Displays the list
• Why: Keeps logic and UI separate, easier to maintain

👉 Real-World Example: Back office team updates filters without touching UI rendering code.

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2. Custom Hook Composition

Use Case: Fetch customer profile data

• useCustomerData.ts: Fetches and caches user data
• CustomerProfile.tsx: Displays user info
• Why: Reusable logic across multiple components

👉 Real-World Example: Used in both the dashboard and customer support panel.

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3. Reducer Pattern

Use Case: Complex loan form with steps

• LoanForm.tsx: Uses useReducer for field management and validation
• Why: Centralized and predictable form state

👉 Real-World Example: Loan officers need full control over validation states and transitions.

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4. Provider Pattern

Use Case: User authentication and role management

• UserProvider.tsx: Context for user session
• Dashboard.tsx: Shows sections based on user role
• Why: Clean global state management without prop drilling

👉 Real-World Example: Displaying different dashboards for admin, agent, and customer.

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5. Higher-Order Component (HOC)

Use Case: Add access control to admin-only views

• withAdminGuard.tsx: Wraps any component
• AdminPanel.tsx: Secured behind HOC
• Why: DRY approach to reuse logic

👉 Real-World Example: Hide certain tabs unless the user is a branch manager.

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6. Compound Components

Use Case: Customer support chat widget

• Chat: Main component
• Chat.Header, Chat.Body, Chat.Input
• Why: Flexible yet tightly coupled composition

👉 Real-World Example: Let support team adjust UI but maintain structure.

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7. Props Combination Pattern

Use Case: Transaction filter settings

• TransactionFilter.tsx: Accepts combined props (status, type, date)
• Why: Flexible API for developers using your component

👉 Real-World Example: Advanced filters for operations team.

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8. Controlled Component

Use Case: Transfer amount input with limits

• TransferForm.tsx: Controls amount, validates against balance
• Why: Full control over validation and state

👉 Real-World Example: Block user if they exceed daily limit.

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9. Error Boundary

Use Case: Prevent crash from broken widgets

• ErrorBoundary.tsx: Wraps risky components (e.g., charts)
• Why: Show fallback UI instead of breaking entire page

👉 Real-World Example: Graph API fails, show “data unavailable” instead of white screen.

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10. Forward Ref

Use Case: Focus input on page load (e.g., OTP input)

• OtpInput.tsx: Exposes ref to focus from parent
• Why: Imperative interaction support

👉 Real-World Example: Automatically focus on first OTP field after login.

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11. Lazy Loading

Use Case: Load loan calculator only when user opens tab

• LoanCalculator.tsx: Lazy loaded in App.tsx
• Why: Reduce initial bundle size

👉 Real-World Example: Improve app speed by splitting features.

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12. Memoization

Use Case: Customer segmentation analytics

• SegmentList.tsx: Memoized render to avoid recomputation
• Why: Optimize performance

👉 Real-World Example: Avoid rerendering large tables when unrelated state changes.

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🧪 Run It

npm install
npm run dev

Visit http://localhost:5173 to see each pattern rendered in the UI.

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📚 Why It Matters

In large-scale apps like banking dashboards, applying the right pattern:

• Improves maintainability
• Ensures performance
• Enables scalability
• Enhances developer collaboration

Use this repo as a reference, learning tool, or a starting point for your own app architecture.

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🎥 Bonus: Tutorial Scripts (Coming Soon)

I am preparing step-by-step YouTube tutorials explaining how and why to use each pattern, using this codebase.

Feel free to contribute improvements or request a new pattern