giuseppe-trisciuoglio/shadcn-ui

shadcn/ui Component Patterns

Build accessible, customizable UI components with shadcn/ui, Radix UI, and Tailwind CSS.

Overview

• Components are copied into your project — you own and customize the code
• Built on Radix UI primitives for full accessibility
• Styled with Tailwind CSS and CSS variables for theming
• CLI-based installation: npx shadcn@latest add <component>

When to Use

Activate when user requests involve:

• "Set up shadcn/ui", "initialize shadcn", "add shadcn components"
• "Install button/input/form/dialog/card/select/toast/table/chart"
• "React Hook Form", "Zod validation", "form with validation"
• "accessible components", "Radix UI", "Tailwind theme"
• "shadcn button", "shadcn dialog", "shadcn sheet", "shadcn table"
• "dark mode", "CSS variables", "custom theme"
• "charts with Recharts", "bar chart", "line chart", "pie chart"

Quick Reference

Available Components

| Component | Install Command | Description | |-----------|----------------|-------------| | button | npx shadcn@latest add button | Variants: default, destructive, outline, secondary, ghost, link | | input | npx shadcn@latest add input | Text input field | | form | npx shadcn@latest add form | React Hook Form integration with validation | | card | npx shadcn@latest add card | Container with header, content, footer | | dialog | npx shadcn@latest add dialog | Modal overlay | | sheet | npx shadcn@latest add sheet | Slide-over panel (top/right/bottom/left) | | select | npx shadcn@latest add select | Dropdown select | | toast | npx shadcn@latest add toast | Notification toasts | | table | npx shadcn@latest add table | Data table | | menubar | npx shadcn@latest add menubar | Desktop-style menubar | | chart | npx shadcn@latest add chart | Recharts wrapper with theming | | textarea | npx shadcn@latest add textarea | Multi-line text input | | checkbox | npx shadcn@latest add checkbox | Checkbox input | | label | npx shadcn@latest add label | Accessible form label |

Instructions

Initialize Project

# New Next.js project
npx create-next-app@latest my-app --typescript --tailwind --eslint --app
cd my-app
npx shadcn@latest init

# Existing project
npm install tailwindcss-animate class-variance-authority clsx tailwind-merge lucide-react
npx shadcn@latest init

# Install components
npx shadcn@latest add button input form card dialog select toast

Basic Component Usage

// Button with variants and sizes
import { Button } from "@/components/ui/button"

<Button variant="default">Default</Button>
<Button variant="destructive" size="sm">Delete</Button>
<Button variant="outline" disabled>Loading...</Button>

Form with Zod Validation

"use client"

import { zodResolver } from "@hookform/resolvers/zod"
import { useForm } from "react-hook-form"
import { z } from "zod"
import { Button } from "@/components/ui/button"
import { Form, FormControl, FormField, FormItem, FormLabel, FormMessage } from "@/components/ui/form"
import { Input } from "@/components/ui/input"

const formSchema = z.object({
  email: z.string().email("Invalid email"),
  password: z.string().min(8, "Password must be at least 8 characters"),
})

export function LoginForm() {
  const form = useForm<z.infer<typeof formSchema>>({
    resolver: zodResolver(formSchema),
    defaultValues: { email: "", password: "" },
  })

  return (
    <Form {...form}>
      <form onSubmit={form.handleSubmit(console.log)} className="space-y-4">
        <FormField name="email" control={form.control} render={({ field }) => (
          <FormItem>
            <FormLabel>Email</FormLabel>
            <FormControl><Input type="email" {...field} /></FormControl>
            <FormMessage />
          </FormItem>
        )} />
        <FormField name="password" control={form.control} render={({ field }) => (
          <FormItem>
            <FormLabel>Password</FormLabel>
            <FormControl><Input type="password" {...field} /></FormControl>
            <FormMessage />
          </FormItem>
        )} />
        <Button type="submit">Login</Button>
      </form>
    </Form>
  )
}

See references/forms-and-validation.md for advanced multi-field forms, contact forms with API submission, and login card patterns.

Dialog (Modal)

import { Button } from "@/components/ui/button"
import { Dialog, DialogContent, DialogHeader, DialogTitle, DialogTrigger } from "@/components/ui/dialog"

<Dialog>
  <DialogTrigger asChild>
    <Button variant="outline">Open</Button>
  </DialogTrigger>
  <DialogContent>
    <DialogHeader>
      <DialogTitle>Edit Profile</DialogTitle>
    </DialogHeader>
    {/* content */}
  </DialogContent>
</Dialog>

Toast Notification

// 1. Add <Toaster /> to app/layout.tsx
import { Toaster } from "@/components/ui/toaster"

// 2. Use in components
import { useToast } from "@/components/ui/use-toast"

const { toast } = useToast()
toast({ title: "Success", description: "Changes saved." })
toast({ variant: "destructive", title: "Error", description: "Something went wrong." })

Bar Chart

import { Bar, BarChart, CartesianGrid, XAxis } from "recharts"
import { ChartContainer, ChartTooltipContent } from "@/components/ui/chart"

const chartConfig = {
  desktop: { label: "Desktop", color: "var(--chart-1)" },
} satisfies import("@/components/ui/chart").ChartConfig

<ChartContainer config={chartConfig} className="min-h-[200px] w-full">
  <BarChart data={data}>
    <CartesianGrid vertical={false} />
    <XAxis dataKey="month" />
    <Bar dataKey="desktop" fill="var(--color-desktop)" radius={4} />
    <ChartTooltip content={<ChartTooltipContent />} />
  </BarChart>
</ChartContainer>

See references/charts-components.md for Line, Area, and Pie chart examples.

Examples

Login Form with Validation

"use client"
import { zodResolver } from "@hookform/resolvers/zod"
import { useForm } from "react-hook-form"
import { z } from "zod"
import { Button } from "@/components/ui/button"
import { Form, FormControl, FormField, FormItem, FormLabel, FormMessage } from "@/components/ui/form"
import { Input } from "@/components/ui/input"

const formSchema = z.object({
  email: z.string().email("Invalid email"),
  password: z.string().min(8, "Min 8 characters"),
})

export function LoginForm() {
  const form = useForm<z.infer<typeof formSchema>>({
    resolver: zodResolver(formSchema),
    defaultValues: { email: "", password: "" },
  })

  return (
    <Form {...form}>
      <form onSubmit={form.handleSubmit(console.log)} className="space-y-4">
        <FormField name="email" control={form.control} render={({ field }) => (
          <FormItem>
            <FormLabel>Email</FormLabel>
            <FormControl><Input type="email" {...field} /></FormControl>
            <FormMessage />
          </FormItem>
        )} />
        <FormField name="password" control={form.control} render={({ field }) => (
          <FormItem>
            <FormLabel>Password</FormLabel>
            <FormControl><Input type="password" {...field} /></FormControl>
            <FormMessage />
          </FormItem>
        )} />
        <Button type="submit">Login</Button>
      </form>
    </Form>
  )
}

Data Table with Actions

import { ColumnDef } from "@tanstack/react-table"
import { Button } from "@/components/ui/button"
import { Checkbox } from "@/components/ui/checkbox"
import { DataTable } from "@/components/ui/data-table"

const columns: ColumnDef<User>[] = [
  { id: "select", header: ({ table }) => (
    <Checkbox checked={table.getIsAllPageRowsSelected()} />
  ), cell: ({ row }) => (
    <Checkbox checked={row.getIsSelected()} />
  )},
  { accessorKey: "name", header: "Name" },
  { accessorKey: "email", header: "Email" },
  { id: "actions", cell: ({ row }) => (
    <Button variant="ghost" size="sm">Edit</Button>
  )},
]

Dialog with Form

import { Button } from "@/components/ui/button"
import { Dialog, DialogContent, DialogHeader, DialogTitle, DialogTrigger } from "@/components/ui/dialog"

<Dialog>
  <DialogTrigger asChild>
    <Button variant="outline">Add User</Button>
  </DialogTrigger>
  <DialogContent>
    <DialogHeader>
      <DialogTitle>Add New User</DialogTitle>
    </DialogHeader>
    {/* <LoginForm /> */}
  </DialogContent>
</Dialog>

Toast Notifications

import { useToast } from "@/components/ui/use-toast"
import { Button } from "@/components/ui/button"

const { toast } = useToast()

toast({ title: "Saved", description: "Changes saved successfully." })
toast({ variant: "destructive", title: "Error", description: "Failed to save." })

Best Practices

• Accessibility: Use Radix UI primitives — ARIA attributes are built in
• Client Components: Add "use client" for interactive components (hooks, events)
• Type Safety: Use TypeScript and Zod schemas for form validation
• Theming: Configure CSS variables in globals.css for consistent design
• Customization: Modify component files directly — you own the code
• Path Aliases: Ensure @ alias is configured in tsconfig.json
• Registry Security: Only install components from trusted registries; review generated code before production use
• Dark Mode: Set up with CSS variables strategy and next-themes
• Forms: Always use Form, FormField, FormItem, FormLabel, FormMessage together
• Toaster: Add <Toaster /> once to root layout

Constraints and Warnings

• Not an NPM Package: Components are copied to your project; they are not a versioned dependency
• Registry Security: Components from npx shadcn@latest add are fetched remotely; always verify the registry source is trusted before installation
• Client Components: Most interactive components require "use client" directive
• Radix Dependencies: Ensure all @radix-ui packages are installed
• Tailwind Required: Components rely on Tailwind CSS utilities
• Path Aliases: Configure @ alias in tsconfig.json for imports

References

Consult these files for detailed patterns and code examples:

• references/setup-and-configuration.md — Full installation, tsconfig, tailwind config, CSS variables
• references/ui-components.md — Button, Input, Card, Dialog, Sheet, Select, Toast, Table, Menubar
• references/forms-and-validation.md — React Hook Form + Zod, advanced forms, login card, contact form
• references/charts-components.md — Bar, Line, Area, Pie charts with ChartContainer and theming
• references/nextjs-integration.md — App Router, Server/Client Components, dark mode, metadata
• references/customization.md — Custom variants, CSS variables, cn() utility, extending components