Responsive Design

import 'package:flutter/material.dart';
import 'package:fluttersdk_wind/fluttersdk_wind.dart';

class ResponsiveDesign extends StatelessWidget {
  const ResponsiveDesign({super.key});

  @override
  Widget build(BuildContext context) {
    return WFlexContainer(
      className: 'w-full h-full justify-center items-center flex-col bg-gray-200',
      children: [
        WCard(
          className: 'sm:w-full lg:w-100 p-4 bg-white rounded-lg items-center justify-center',
          child: WText('Full width on small screens, fixed on large.', className: 'text-black'),
        ),
        WCard(
          className: 'lg:w-full p-4 bg-white rounded-lg items-center justify-center',
          child: WText('Full width on large screens.', className: 'text-black'),
        ),
      ],
    );
  }
}

Basic Usage#

Prefix any utility with a breakpoint name to apply it from that width upward:

WCard(
  className: 'sm:w-full md:w-1/2 lg:w-100 p-4 bg-white rounded-lg',
  child: WText('Resizes as the viewport grows.', className: 'text-black'),
);

Breakpoints are min-width based: lg:w-100 takes effect once the available width is at least the lg breakpoint and stays in effect at wider sizes.

Default Breakpoints#

Wind ships with five breakpoints out of the box. The width is the minimum screen width, in logical pixels, at which the prefix activates:

Retrieve the full map programmatically:

final screens = WindTheme.getScreens();

How It Works#

Wind reads each space-separated token in a className. When a token carries a known breakpoint prefix, the screens parser checks the current MediaQuery width against WindTheme.getScreenValue(prefix). If the width meets or exceeds that value, the prefix is stripped and the underlying utility is applied; otherwise the token is skipped.

Because the check is min-width based, listing several breakpoints lets the larger one win at wider sizes:

// w-full below lg, then a fixed 100-unit width from lg upward.
WContainer(className: 'sm:w-full lg:w-100');

The same prefix machinery also resolves dark:/light: and operating-system prefixes (ios:, android:, web:, ...), so a single token can target a breakpoint and a mode together.

Managing Breakpoints#

Add, update, or remove custom breakpoints through WindTheme. Do this once during setup, before the widgets that depend on them build:

// Add a custom breakpoint.
WindTheme.addScreen('watch', 300);

// Update an existing breakpoint.
WindTheme.updateScreen('watch', 400);

// Remove a custom breakpoint.
WindTheme.removeScreen('watch');

Once registered, a custom prefix behaves exactly like the built-in ones: watch:w-full applies from its width upward.

Best Practices#

• Order tokens from smallest to largest breakpoint so the intent reads top-down (sm:... md:... lg:...).
• Remember breakpoints are min-width based: a value with no prefix is the base, and each prefix overrides it from its width upward.
• Register custom breakpoints during app setup, not inside build, so the map is stable across rebuilds.
• Combine breakpoint and mode prefixes when needed (lg:dark:bg-gray-800) rather than duplicating widgets.

Related Documentation#

• Dark Mode — the dark: prefix that shares this resolution model.
• State-Based Styling — applying styles for widget states.
• Width — the w-* utilities most often made responsive.
• Display — hide/show utilities with breakpoint prefixes.