Fluid Layout

Demo: jamesblasco.github.io/fluid_layout

Fluid layouts allow you to create a responsive layout for mobile, web and desktop from a single codebase.

Let’s get started

Install it

Follow the installation process here

Understand fluid layout

The fluid layout aims to help to build a responsive experience through all the different screen sizes. Based on the boostrap approach, FluidLayout calculates a padding content (fluid_padding) that changes depending on the parent size. The Fluid widget uses that padding to set its size

The screen sizes are divided into 6 breakpoints: xs, s, m, l, xl, and can be accessed through FluidLayout.of(context).fluidBreakpoint or context.breakpoint.

You can create values(int, num, objects, functions, … whatever variable type) for different screen sizes thanks to the class FluidValue. The easiest way is:

final value = context.fluid(defaultValue, 
  xs: xsValue,  //if null xs would be defaultValue
  s:  sValue,   //if null s would be defaultValue
  m:  mValue,   //if null m would be defaultValue
  l:  lValue,   //if null l would be defaultValue
  xl: xlValue   //if null xl would be defaultValue
 )

Examples

FluidLayout & Fluid

See web example

class BasicFluidLayout extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.grey[200],
      body: Container(
        child: FluidLayout(
          child: Fluid(
            child: Container(
              color: Colors.blue,
              child: Center(
                child: Text(
                  'Fluid width',
                  style: TextStyle(color: Colors.white),
                ),
              ),
            ),
          ),
        ),
      ),
    );
  }
}

There is a fixed horizontalPadding param that can be changed to all the FluidLayout or just for a Fluid container

For CustomScrollView there is a SliverFluid equivalent to Fluid

FluidGridView

See FluidGridView web example

FluidGridView(
  children: List.filled(
    100,
    FluidCell.withFluidHeight(
      size: context.fluid(3, m: 3, s: 4, xs: 6),
      heightSize: context.fluid(3, m: 3, s: 4, xs: 6),
      child: CustomCard(
        color: Colors.red,
        child: Center(child: Text('Item')),
      )),
    ),
)

Customizable params [double spacing, ScrollPhysics physics, bool shrinkWrap] and bool fluid

FluidCell has three methods to build the cell:

FluidCell.fit({size, child})
FluidCell.withFluidHeight({size, heightSize, child})
FluidCell.withFixedHeight({size, height, child})

For CustomScrollView there is a SliverFluidGrid equivalent to FluidGridView

Conditional Layout

See Conditional Layout web example

if(FluidLayout.of(context).fluidBreakpoint.isLargerThanM)
   return Container(color: Colors.red)
else
   return Container(color: Colors.red)

Remember you can use context.breakpoint as FluidLayout.of(context).fluidBreakpoint

Combine full width widgets with fluid layouts

Fluid layouts can be built everywhere inside the app and they will calculate their constraints based on their parents’ sizes, also they can combine very easily in cases we need full-screen widgets.