Challenges with Flutter responsive design using the flutter_screenutil library

I’m currently developing a Flutter application and utilizing the flutter_screenutil library to implement a responsive layout based on 390x844 design specifications. However, I’m facing challenges with how the layout adapts to smaller screen sizes.

While testing on devices with different dimensions, I’ve noticed that the layout does not appropriately scale. I attempted to use FittedBox, but it ended up creating a lot of inconsistencies, especially with button sizes which fluctuate unpredictably across various screens.

Should I consider switching to a ScrollView instead of striving for a perfect fit? Or is there a more effective approach to tackle this issue of responsive design?

Here’s my main app setup:

void main() {
  WidgetsFlutterBinding.ensureInitialized();
  runApp(const AppRoot());
}

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

  @override
  Widget build(BuildContext context) {
    return ScreenUtilInit(
      designSize: const Size(390, 844),
      minTextAdapt: true,
      splitScreenMode: true,
      builder: (context, child) {
        return const MaterialApp(
          debugShowCheckedModeBanner: false,
          home: LoginScreen(),
        );
      },
    );
  }
}

And here’s my login screen widget:

class LoginScreen extends StatefulWidget {
  const LoginScreen({super.key});

  @override
  State<LoginScreen> createState() => _LoginScreenState();
}

class _LoginScreenState extends State<LoginScreen> {
  @override
  Widget build(BuildContext context) {
    return SafeArea(
      child: Scaffold(
        body: Padding(
          padding: EdgeInsets.symmetric(horizontal: 20.w),
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.center,
            children: [
              SizedBox(height: 40.h),
              Center(
                child: Image.asset("assets/icons/app_logo.png"),
              ),
              SizedBox(height: 50.h),
              Text(
                "Welcome Back!",
                style: TextStyle(
                  fontSize: 28.sp,
                  fontWeight: FontWeight.w600,
                  color: Colors.black87,
                  fontFamily: "Roboto",
                ),
              ),
              SizedBox(height: 15.h),
              Text(
                "Please sign in to continue",
                style: TextStyle(
                  fontSize: 16.sp,
                  fontWeight: FontWeight.w300,
                  color: Colors.grey,
                  fontFamily: "Roboto",
                ),
              ),
              SizedBox(height: 40.h),
              _buildSocialButton(
                "Continue with Gmail",
                "assets/icons/gmail.png",
                Colors.red,
              ),
              SizedBox(height: 15.h),
              _buildSocialButton(
                "Continue with Apple ID",
                "assets/icons/apple_icon.png",
                Colors.black,
              ),
              SizedBox(height: 30.h),
              _buildActionButton(
                "Create Account",
                const Color(0xFF4285F4),
                Colors.white,
              ),
              SizedBox(height: 15.h),
              _buildActionButton(
                "Login",
                const Color(0xFFE3F2FD),
                const Color(0xFF4285F4),
              ),
            ],
          ),
        ),
      ),
    );
  }

  Widget _buildSocialButton(String title, String iconPath, Color iconColor) {
    return SizedBox(
      height: 55.h,
      width: double.infinity,
      child: ElevatedButton(
        onPressed: () {},
        style: ElevatedButton.styleFrom(
          shape: RoundedRectangleBorder(
            borderRadius: BorderRadius.circular(28.r),
          ),
        ),
        child: Row(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            Image.asset(iconPath, width: 24.w, height: 24.h),
            SizedBox(width: 12.w),
            Text(
              title,
              style: TextStyle(
                fontSize: 15.sp,
                fontWeight: FontWeight.w500,
                color: Colors.black87,
                fontFamily: "Roboto",
              ),
            ),
          ],
        ),
      ),
    );
  }

  Widget _buildActionButton(String title, Color bgColor, Color textColor) {
    return SizedBox(
      height: 55.h,
      width: double.infinity,
      child: ElevatedButton(
        onPressed: () {},
        style: ElevatedButton.styleFrom(
          backgroundColor: bgColor,
          shape: RoundedRectangleBorder(
            borderRadius: BorderRadius.circular(28.r),
          ),
        ),
        child: Text(
          title,
          style: TextStyle(
            fontSize: 15.sp,
            fontWeight: FontWeight.w500,
            color: textColor,
            fontFamily: "Roboto",
          ),
        ),
      ),
    );
  }
}

I appreciate any advice you could provide!

Honestly, screenutil’s overrated for complex layouts. Use Expanded and Flexible widgets instead of fixed heights - they handle weird screen ratios way better than .h extensions. Your 55.h buttons probably look fine on similar phones but get wonky on different sizes. Set a base minHeight and let the widgets breathe naturally. Works better than fighting the scaling algorithm.

yeah, screenutil gets wonky with big size differences. add ensureScreenSize: false to your ScreenUtilInit - fixed my button issues on small screens. also throw in some max/min values for important spacing like SizedBox(height: math.min(40.h, 30)) so things don’t get too cramped or spaced out.

Been fighting screenutil on a client project and the main issue is that 390x844 base design falls apart on edge cases - older Android phones or wide tablets. Your code’s solid but the scaling math breaks when aspect ratios get weird. Don’t ditch screenutil completely though. Add fallback logic instead. Keep your current setup but throw in bounds checking - like height: math.max(45, 55.h) for buttons so they can’t shrink below usable size. When scaling goes haywire on problem screens, just switch to a simplified layout. That Column setup definitely needs ScrollView backup. I wrap everything in SingleChildScrollView with physics: ClampingScrollPhysics() - normal screens work fine while compact devices don’t overflow. Way cleaner than forcing perfect fits across every screen size.

I’ve been fighting screenutil for months in production - it works way better when you mix it with manual breakpoints instead of relying on pure scaling. Your setup’s fine, but expecting linear scaling across all devices is where things fall apart.

What saved me was going hybrid - keep screenutil for text and small spacing, but use MediaQuery.of(context).size.width for custom scaling factors across different screen ranges. Under 350px width, I multiply .h and .w by 0.85. For tablets over 600px, I cap scaling at 1.2x so elements don’t get massive.

Saw you’re using fixed 55.h button heights - make those responsive to screen density instead. Try height: MediaQuery.of(context).size.height * 0.065 for more predictable results across Android devices. That Column layout’s gonna need ScrollView as backup for compact screens anyway.

I’ve hit this exact issue with flutter_screenutil across different device sizes. It’s super common when you rely too much on proportional scaling between phones and tablets.

What worked for me was ditching pure scaling for breakpoint-based responsive design. Use MediaQuery to check screen width and switch up your layout strategy for tablets vs phones. On smaller screens, I throw everything in a ScrollView and set fixed minimum sizes for critical stuff like buttons - stops all that weird sizing behavior.

Also try setting min/max constraints on key UI elements. Don’t just use .w and .h extensions everywhere - wrap your buttons in ConstrainedBox with reasonable bounds. Keeps buttons from getting tiny on small devices or massive on big screens.

That FittedBox inconsistency? It’s fighting to maintain aspect ratios when screen proportions don’t match your design specs. Swap in Flexible widgets with specific flex values instead - way better control over how space gets distributed.

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