1.5 Layouts & Templates - Cordoba Institute of Knowledge

Learning Objectives

By the end of this section, you will be able to:

Implement consistent layouts across your Next.js application
Create reusable layout patterns for different sections
Set up proper layout hierarchies and nesting
Optimize layout performance and user experience
Apply layout patterns to the VSL Service Center structure

Duration: 2-3 hours

Part 1: Strategic Understanding

Review if needed: Layouts and Templates

Overview

Next.js App Router provides powerful layout features for creating consistent UI patterns. Understanding layouts is crucial for building maintainable applications.

What are Layouts?

Layouts are shared UI that persists across route changes and maintains state during navigation.

Key Characteristics

Layout Characteristics

Shared UI across multiple pages
Maintains state during navigation
Renders once and stays mounted
Perfect for navigation, headers, footers

Layout Benefits

Consistent user experience
Performance optimization
State preservation
Reduced re-rendering

Root Layout

The root layout wraps all pages and is required in every Next.js app.

// app/layout.tsx
import type { Metadata } from "next";
import { Inter } from "next/font/google";
import "./globals.css";

const inter = Inter({ subsets: ["latin"] });

export const metadata: Metadata = {
  title: "My App",
  description: "Generated by create next app",
};

export default function RootLayout({
  children,
}: {
  children: React.ReactNode;
}) {
  return (
    <html lang="en" className={inter.className}>
      <body>
        <header>
          <nav>
            <a href="/">Home</a>
            <a href="/about">About</a>
            <a href="/contact">Contact</a>
          </nav>
        </header>
        <main>{children}</main>
        <footer>
          <p>&copy; 2024 My App. All rights reserved.</p>
        </footer>
      </body>
    </html>
  );
}

Nested Layouts

Layouts can be nested to create hierarchical UI structures.

// app/dashboard/layout.tsx
import Sidebar from "@/components/Sidebar";

export default function DashboardLayout({
  children,
}: {
  children: React.ReactNode;
}) {
  return (
    <div className="dashboard-layout">
      <Sidebar />
      <div className="dashboard-content">{children}</div>
    </div>
  );
}

Layout Hierarchy

app/
├── layout.tsx              # Root layout (wraps everything)
├── dashboard/
│   ├── layout.tsx          # Dashboard layout (wraps dashboard pages)
│   ├── page.tsx            # /dashboard
│   └── settings/
│       ├── layout.tsx      # Settings layout (wraps settings pages)
│       └── page.tsx        # /dashboard/settings

Basic Layout Patterns

// app/layout.tsx
export default function RootLayout({
  children,
}: {
  children: React.ReactNode;
}) {
  return (
    <html lang="en">
      <body>
        <div className="min-h-screen flex flex-col">
          <header className="bg-white shadow-sm">
            <nav className="max-w-7xl mx-auto px-4 sm:px-6 lg:px-8">
              <div className="flex justify-between items-center">
                <div className="flex space-x-8">
                  <a href="/" className="text-gray-900">
                    Home
                  </a>
                  <a href="/about" className="text-gray-900">
                    About
                  </a>
                  <a href="/contact" className="text-gray-900">
                    Contact
                  </a>
                </div>
              </div>
            </nav>
          </header>

          <main className="flex-1">{children}</main>

          <footer className="bg-gray-800 text-white">
            <div className="max-w-7xl mx-auto px-4 sm:px-6 lg:px-8">
              <p>&copy; 2024 My App. All rights reserved.</p>
            </div>
          </footer>
        </div>
      </body>
    </html>
  );
}

Dashboard Layout

// app/dashboard/layout.tsx
import Sidebar from "@/components/Sidebar";
import Header from "@/components/Header";

export default function DashboardLayout({
  children,
}: {
  children: React.ReactNode;
}) {
  return (
    <div className="dashboard-layout">
      <Sidebar />
      <div className="dashboard-main">
        <Header />
        <div className="dashboard-content">{children}</div>
      </div>
    </div>
  );
}

Layout with Metadata

// app/blog/layout.tsx
import { Metadata } from "next";

export const metadata: Metadata = {
  title: "Blog - My App",
  description: "Read our latest blog posts",
};

export default function BlogLayout({
  children,
}: {
  children: React.ReactNode;
}) {
  return (
    <div className="blog-layout">
      <aside className="blog-sidebar">
        <h2>Categories</h2>
        {/* Category links */}
      </aside>
      <main className="blog-main">{children}</main>
    </div>
  );
}

Best Practices for Module 1

Layout Design

Keep Layouts Simple: Focus on shared UI elements and avoid complex logic
Use Nested Layouts: Create hierarchical layouts for better organization
Optimize Performance: Minimize re-renders and use proper state management
Handle Loading States: Provide appropriate loading states

Key Takeaway: Layouts are powerful tools for creating consistent UI patterns. Use them for shared UI that should persist across routes, like navigation, headers, and footers.

Layout vs Template

Layout

Shared UI that persists across route changes - Maintains state during navigation - Perfect for navigation, headers, footers - Renders once and stays mounted

Template

Creates new instance for each route - Re-renders on every navigation - Perfect for animations, enter/exit effects - Useful for page transitions

Layout Hierarchy Concept

Next.js layouts create a hierarchy where child layouts wrap their parent layouts. This allows you to:

Share common UI elements across multiple pages
Maintain state during navigation
Create section-specific layouts for different parts of your app
Optimize performance by reducing re-renders

VSL Service Center Layout Strategy

For the VSL Service Center, we’ll create a layout hierarchy that includes:

Root Layout: Global navigation, footer, and authentication state
Auth Layout: Clean, centered design for login/register pages
Master Layout: Navigation and breadcrumbs for master data sections
Transaction Layout: Specialized layout for transaction workflows

Part 2: Hands-On Implementation

Exercise 1: Create Root Layout

Create the root layout with proper structure:

app/layout.tsx

import type { Metadata } from "next";
import { Inter } from "next/font/google";
import "./globals.css";
import RootLayoutClient from "@/components/layout/RootLayoutClient";

const inter = Inter({ subsets: ["latin"] });

export const metadata: Metadata = {
  title: "VSL Service Center",
  description: "Warehouse Management System",
  keywords: ["warehouse", "management", "inventory", "logistics"],
};

export default function RootLayout({
  children,
}: {
  children: React.ReactNode;
}) {
  return (
    <html lang="en" className={inter.className}>
      <body className="min-h-screen bg-gray-50">
        <RootLayoutClient>{children}</RootLayoutClient>
      </body>
    </html>
  );
}

Create the root layout client component:

components/layout/RootLayoutClient.tsx

"use client";

import { useState, useEffect } from "react";
import { usePathname } from "next/navigation";
import Navbar from "./Navbar";
import Sidebar from "./Sidebar";
import Footer from "./Footer";

export default function RootLayoutClient({
  children,
}: {
  children: React.ReactNode;
}) {
  const [sidebarOpen, setSidebarOpen] = useState(false);
  const [isAuthenticated, setIsAuthenticated] = useState(false);
  const pathname = usePathname();

  useEffect(() => {
    const token = localStorage.getItem("token");
    setIsAuthenticated(!!token);
  }, []);

  // Don't show navbar/sidebar on auth pages
  const isAuthPage =
    pathname.startsWith("/login") || pathname.startsWith("/register");

  return (
    <div className="min-h-screen flex flex-col">
      {!isAuthPage && (
        <>
          <Navbar onMenuClick={() => setSidebarOpen(!sidebarOpen)} />
          <div className="flex flex-1">
            <Sidebar
              isOpen={sidebarOpen}
              onClose={() => setSidebarOpen(false)}
            />
            <main className="flex-1 overflow-x-hidden">{children}</main>
          </div>
        </>
      )}

      {isAuthPage && <main className="flex-1">{children}</main>}

      {!isAuthPage && <Footer />}
    </div>
  );
}

Exercise 2: Create Authentication Layout

Create the auth layout for login/register pages:

app/(auth)/layout.tsx

import Image from "next/image";
import logo from "@/public/images/TSSCL_Logo.png";

export default function AuthLayout({
  children,
}: {
  children: React.ReactNode;
}) {
  return (
    <div className="min-h-screen flex items-center justify-center bg-gray-50 py-12 px-4 sm:px-6 lg:px-8">
      <div className="max-w-md w-full space-y-8">
        <div className="text-center">
          <Image
            src={logo}
            alt="VSL Service Center"
            width={80}
            height={80}
            className="mx-auto"
          />
          <h2 className="mt-6 text-3xl font-extrabold text-gray-900">
            VSL Service Center
          </h2>
          <p className="mt-2 text-sm text-gray-600">
            Warehouse Management System
          </p>
        </div>

        <div className="bg-white py-8 px-6 shadow rounded-lg">
          {children}
        </div>
      </div>
    </div>
  );
}

Exercise 3: Create Master Data Layout

Create the master data layout with navigation:

app/master/layout.tsx

import Link from "next/link";
import { Metadata } from "next";

export const metadata: Metadata = {
  title: "Master Data - VSL Service Center",
  description:
    "Manage warehouse master data including customers, suppliers, and materials",
};

export default function MasterLayout({
  children,
}: {
  children: React.ReactNode;
}) {
  const masterMenuItems = [
    { name: "Customers", href: "/master/customers", icon: "Users" },
    { name: "Suppliers", href: "/master/suppliers", icon: "Building" },
    { name: "Materials", href: "/master/materials", icon: "Package" },
    { name: "Locations", href: "/master/locations", icon: "MapPin" },
    { name: "Operators", href: "/master/operators", icon: "User" },
    { name: "Work Centers", href: "/master/work-centers", icon: "Factory" },
  ];

  return (
    <div className="container mx-auto px-4 py-8">
      <div className="mb-8">
        <h1 className="text-3xl font-bold text-gray-900">
          Master Data Management
        </h1>
        <p className="text-gray-600 mt-2">
          Manage your warehouse master data and configuration
        </p>
      </div>

      <div className="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-3 gap-6 mb-8">
        {masterMenuItems.map((item) => (
          <Link
            key={item.href}
            href={item.href}
            className="bg-white p-6 rounded-lg shadow-md hover:shadow-lg transition-shadow border border-gray-200 hover:border-blue-300">
            <div className="flex items-center">
              <span className="text-2xl mr-3">{item.icon}</span>
              <div>
                <h3 className="text-lg font-semibold text-gray-900">
                  {item.name}
                </h3>
                <p className="text-sm text-gray-600">
                  Manage {item.name.toLowerCase()}
                </p>
              </div>
            </div>
          </Link>
        ))}
      </div>

      <div className="bg-white rounded-lg shadow-md">{children}</div>
    </div>
  );
}

Transaction Layout

Transaction Layout (app/transactions/layout.tsx):

app/transactions/layout.tsx

import Link from "next/link";
import { Metadata } from "next";

export const metadata: Metadata = {
  title: "Transactions - VSL Service Center",
  description:
    "Manage warehouse transactions including inward and outward operations",
};

export default function TransactionLayout({
  children,
}: {
  children: React.ReactNode;
}) {
  const transactionMenuItems = [
    { name: "Material Inward", href: "/transactions/inward", icon: "📥" },
    { name: "Material Outward", href: "/transactions/outward", icon: "📤" },
    { name: "Packing", href: "/transactions/packing", icon: "📦" },
    { name: "Loading Slip", href: "/transactions/loading-slip", icon: "🚛" },
    {
      name: "Delivery Challan",
      href: "/transactions/delivery-challan",
      icon: "📋",
    },
    { name: "Production Entry", href: "/transactions/production", icon: "⚙️" },
  ];

  return (
    <div className="container mx-auto px-4 py-8">
      <div className="mb-8">
        <h1 className="text-3xl font-bold text-gray-900">
          Transaction Management
        </h1>
        <p className="text-gray-600 mt-2">
          Process warehouse transactions and operations
        </p>
      </div>

      <div className="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-3 gap-6 mb-8">
        {transactionMenuItems.map((item) => (
          <Link
            key={item.href}
            href={item.href}
            className="bg-white p-6 rounded-lg shadow-md hover:shadow-lg transition-shadow border border-gray-200 hover:border-green-300">
            <div className="flex items-center">
              <span className="text-2xl mr-3">{item.icon}</span>
              <div>
                <h3 className="text-lg font-semibold text-gray-900">
                  {item.name}
                </h3>
                <p className="text-sm text-gray-600">
                  Process {item.name.toLowerCase()}
                </p>
              </div>
            </div>
          </Link>
        ))}
      </div>

      <div className="bg-white rounded-lg shadow-md">{children}</div>
    </div>
  );
}

Template Implementation

Page Transition Template

Template (app/template.tsx):

app/template.tsx

"use client";

import { useEffect, useState } from "react";
import { usePathname } from "next/navigation";

export default function Template({ children }: { children: React.ReactNode }) {
  const [isLoading, setIsLoading] = useState(false);
  const pathname = usePathname();

  useEffect(() => {
    setIsLoading(true);
    const timer = setTimeout(() => setIsLoading(false), 300);
    return () => clearTimeout(timer);
  }, [pathname]);

  return (
    <div
      className={`transition-opacity duration-300 ${
        isLoading ? "opacity-0" : "opacity-100"
      }`}>
      {children}
    </div>
  );
}

Loading Templates

Loading Template (app/loading.tsx):

app/loading.tsx

export default function Loading() {
  return (
    <div className="flex items-center justify-center min-h-screen">
      <div className="animate-spin rounded-full h-32 w-32 border-b-2 border-blue-500"></div>
    </div>
  );
}

Master Loading Template (app/master/loading.tsx):

app/master/loading.tsx

export default function MasterLoading() {
  return (
    <div className="container mx-auto px-4 py-8">
      <div className="mb-8">
        <div className="h-8 bg-gray-200 rounded w-1/3 animate-pulse"></div>
        <div className="h-4 bg-gray-200 rounded w-1/2 mt-2 animate-pulse"></div>
      </div>

      <div className="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-3 gap-6 mb-8">
        {Array.from({ length: 6 }).map((_, i) => (
          <div key={i} className="bg-white p-6 rounded-lg shadow-md">
            <div className="flex items-center">
              <div className="w-8 h-8 bg-gray-200 rounded mr-3 animate-pulse"></div>
              <div>
                <div className="h-4 bg-gray-200 rounded w-24 mb-2 animate-pulse"></div>
                <div className="h-3 bg-gray-200 rounded w-32 animate-pulse"></div>
              </div>
            </div>
          </div>
        ))}
      </div>

      <div className="bg-white rounded-lg shadow-md p-8">
        <div className="space-y-4">
          {Array.from({ length: 5 }).map((_, i) => (
            <div
              key={i}
              className="h-4 bg-gray-200 rounded animate-pulse"></div>
          ))}
        </div>
      </div>
    </div>
  );
}

Create a responsive sidebar component:

components/layout/Sidebar.tsx

"use client";

import { useState } from "react";
import Link from "next/link";
import { usePathname } from "next/navigation";

interface SidebarProps {
  isOpen: boolean;
  onClose: () => void;
}

export default function Sidebar({ isOpen, onClose }: SidebarProps) {
  const pathname = usePathname();

  const menuItems = [
    { name: "Dashboard", href: "/dashboard", icon: "📊" },
    { name: "Master Data", href: "/master", icon: "📋" },
    { name: "Transactions", href: "/transactions", icon: "🔄" },
    { name: "Reports", href: "/reports", icon: "📈" },
    { name: "Visitor Management", href: "/visitor", icon: "👥" },
    { name: "YMS", href: "/yms", icon: "🏭" },
  ];

  return (
    <>
      {/* Mobile overlay */}
      {isOpen && (
        <div
          className="fixed inset-0 bg-black bg-opacity-50 z-40 lg:hidden"
          onClick={onClose}
        />
      )}

      {/* Sidebar */}
      <div
        className={`
        fixed top-0 left-0 h-full w-64 bg-white shadow-lg transform transition-transform duration-300 ease-in-out z-50
        ${isOpen ? "translate-x-0" : "-translate-x-full"}
        lg:translate-x-0 lg:static lg:shadow-none
      `}>
        <div className="p-6">
          <h2 className="text-xl font-bold text-gray-800 mb-6">
            Navigation
          </h2>

          <nav className="space-y-2">
            {menuItems.map((item) => (
              <Link
                key={item.href}
                href={item.href}
                className={`
                  flex items-center px-4 py-3 rounded-lg transition-colors
                  ${
                    pathname === item.href
                      ? "bg-blue-100 text-blue-700"
                      : "text-gray-700 hover:bg-gray-100"
                  }
                `}
                onClick={onClose}>
                <span className="mr-3">{item.icon}</span>
                {item.name}
              </Link>
            ))}
          </nav>
        </div>
      </div>
    </>
  );
}

Exercise 5: Test Layout Hierarchy

Create a dashboard-specific layout:

app/dashboard/layout.tsx

import { Metadata } from "next";

export const metadata: Metadata = {
  title: "Dashboard - VSL Service Center",
  description:
    "Warehouse management dashboard with key metrics and insights",
};

export default function DashboardLayout({
  children,
}: {
  children: React.ReactNode;
}) {
  return (
    <div className="container mx-auto px-4 py-8">
      <div className="mb-8">
        <h1 className="text-3xl font-bold text-gray-900">Dashboard</h1>
        <p className="text-gray-600 mt-2">
          Welcome to your warehouse management dashboard
        </p>
      </div>

      <div className="grid grid-cols-1 lg:grid-cols-4 gap-6">
        <div className="lg:col-span-3">{children}</div>

        <div className="lg:col-span-1">
          <div className="bg-white p-6 rounded-lg shadow-md">
            <h3 className="text-lg font-semibold mb-4">Quick Actions</h3>
            <div className="space-y-3">
              <button className="w-full text-left p-3 bg-blue-50 rounded-lg hover:bg-blue-100 transition-colors">
                📥 New Inward
              </button>
              <button className="w-full text-left p-3 bg-green-50 rounded-lg hover:bg-green-100 transition-colors">
                📤 New Outward
              </button>
              <button className="w-full text-left p-3 bg-yellow-50 rounded-lg hover:bg-yellow-100 transition-colors">
                📋 Generate Report
              </button>
            </div>
          </div>
        </div>
      </div>
    </div>
  );
}

Part 3: Reflection & Assessment

Create test pages to verify layout hierarchy:

app/dashboard/page.tsx

export default function DashboardPage() {
  return (
    <div className="bg-white p-6 rounded-lg shadow-md">
      <h2 className="text-2xl font-bold mb-4">Dashboard Content</h2>
      <p>
        This page is wrapped by both the root layout and dashboard layout.
      </p>
    </div>
  );
}

app/master/customers/page.tsx

export default function CustomersPage() {
  return (
    <div className="p-6">
      <h2 className="text-2xl font-bold mb-4">Customer Management</h2>
      <p>This page is wrapped by root layout and master layout.</p>
    </div>
  );
}

Layout Implementation Best Practices

Consistent Structure

Maintain consistent layout structure across all pages

Responsive Design

Ensure layouts work well on all device sizes

Component Organization

Organize layout components logically

Assessment Criteria

Your layout implementation will be evaluated based on:

Layout Structure

Proper layout hierarchy implementation - Consistent UI patterns across pages - Responsive design implementation - Clean and maintainable code structure

User Experience

Smooth navigation between pages - Proper loading states and transitions - Intuitive layout organization - Accessibility compliance

Common Layout Challenges & Solutions

Layout State Management

Challenge: Managing state across different layouts Solution: Use context providers or state management libraries

Responsive Layout Issues

Challenge: Ensuring layouts work on all screen sizes Solution: Use Tailwind CSS responsive utilities and test thoroughly

Layout Performance

Challenge: Large layouts causing performance issues Solution: Split layouts into smaller components and use dynamic imports

Layout Consistency

Challenge: Maintaining consistent styling across layouts Solution: Create a design system and reusable layout components

Reflection Questions

How did implementing layouts change your understanding of Next.js architecture?
- Consider the hierarchy and nesting concepts
- Think about state management across layouts
- Reflect on performance implications
What challenges did you face when creating responsive layouts?
- Mobile vs desktop considerations
- Navigation and sidebar behavior
- Content organization and spacing
How would you optimize the layout performance for a larger application?
- Component splitting strategies
- Lazy loading considerations
- State management optimization

Extension Activities

Layout Patterns:
- Research nested layout patterns
- Study layout composition techniques
- Explore dynamic layout switching
Advanced Layout Features:
- Learn about layout-level code splitting
- Study layout performance optimization
- Explore advanced layout patterns

Next Steps

After completing this lesson, you’ll be ready to move on to Lesson 1.6: Module 1 Assessment, where you’ll:

Test your migrated components and layouts
Demonstrate understanding of Next.js App Router concepts
Complete hands-on exercises and assessments
Prepare for Module 2: Data Integration & API Modernization

Key Takeaway: Well-designed layouts create a consistent user experience and provide a solid foundation for your application. Focus on creating reusable, responsive layouts that enhance usability and performance.

Next.js Migration Course

​Learning Objectives

​Part 1: Strategic Understanding

​Overview

​What are Layouts?

​Key Characteristics

Layout Characteristics

Layout Benefits

​Root Layout

​Nested Layouts

​Layout Hierarchy

​Basic Layout Patterns

​Simple Layout with Navigation

​Dashboard Layout

​Layout with Metadata

​Best Practices for Module 1

​Layout Design

​Layout vs Template

Layout

Template

​Layout Hierarchy Concept

​VSL Service Center Layout Strategy

​Part 2: Hands-On Implementation

​Exercise 1: Create Root Layout

​Exercise 2: Create Authentication Layout

​Exercise 3: Create Master Data Layout

​Transaction Layout

​Template Implementation

​Page Transition Template

​Loading Templates

​Exercise 4: Create Sidebar Component

​Exercise 5: Test Layout Hierarchy

​Part 3: Reflection & Assessment

​Layout Implementation Best Practices

​Assessment Criteria

Layout Structure

User Experience

​Common Layout Challenges & Solutions

​Reflection Questions

​Extension Activities

​Next Steps

Learning Objectives

Part 1: Strategic Understanding

Overview

What are Layouts?

Key Characteristics

Root Layout

Nested Layouts

Layout Hierarchy

Basic Layout Patterns

Simple Layout with Navigation

Dashboard Layout

Layout with Metadata

Best Practices for Module 1

Layout Design

Layout vs Template

Layout Hierarchy Concept

VSL Service Center Layout Strategy

Part 2: Hands-On Implementation

Exercise 1: Create Root Layout

Exercise 2: Create Authentication Layout

Exercise 3: Create Master Data Layout

Transaction Layout

Template Implementation

Page Transition Template

Loading Templates

Exercise 4: Create Sidebar Component

Exercise 5: Test Layout Hierarchy

Part 3: Reflection & Assessment

Layout Implementation Best Practices

Assessment Criteria

Common Layout Challenges & Solutions

Reflection Questions

Extension Activities

Next Steps