number_inc_dec

A flutter widget that accepts numbers along with buttons to increment and decrement. This is a simple TextFormField with buttons and logic to handle factored increments/decrements and with some additional properties like minimum and maximum allowed value. The factor of incrementing/decrementing is also configurable.

Please check the example section which provides granular examples for each options.

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Breaking Changes from v0.7.x

Some major changes are introduced. I am bumping the version to 0.7.x because following changes may break existing users. Please do report for any issues in the repository, which I will try to address.

1. autovalidate has been replaced with autovalidateMode. More details in TextFormField docs

   • In your code replace autovalidate: true to autovalidateMode: AutovalidateMode.always

   • In your code replace autovalidate: false to autovalidateMode: AutovalidateMode.disabled

2. autovalidateMode is by default set to always. The morale behind this is to perform validations similar to html's <input type='number'> tag kind validation performed in chrome. Its not upto the specification but at least mimics to its best.

3. New attribute enableMinMaxClamping is created to and handles the behaviour of clamping the values to min and max when provided. For example if min is -2 and user enter -5 this is auto-corrected to -2. By default this is attribute is set to true.

4. New attribute onChanged is introduced which when provided will be called whenever the user edits the value. Note this callback will not be called if any validation error exists.

5. By default the numbers will be validated for stepped increments like in browser and suggest valid nearest possible values. The intention is to mimic the behaviour of number field in Chrome.

Getting Started

1. Install the latest version of the package by adding it to pubspec.yaml as noted in the install page.

2. Import the number_inc_dec.dart as follows import 'package:number_inc_dec/number_inc_dec.dart';.

3. Utilize the NumberIncrementDecrement as usual like any other flutter widget.

   • e.g.

     NumberInputWithIncrementDecrement(
        controller: TextEditingController(),
        min: -3,
        max: 3,
     ),

Demo with different options

Check the examples sections for the corresponding code snippets.

Configurable options

NumberInputWithIncrementDecrementwidget comes with some configurable options. The same configurations are application for NumberInputPrefabbed widgets.

Property	Type	Purpose	Default Value
controller	TextEditingController	A mandatory text editing controller to be used by the TextFormField.	This is a mandatory field because its the easiest way to access the field's value, when not using a Form widget.
buttonArrangement	ButtonArrangement	Decides the layout of the increment/decrement buttons. Following values are possible. 1. leftEnd 2. rightEnd 3. incLeftDecRight 4.incRightDecLeft	ButtonArrangement.rightEnd
autovalidate	bool	This is passed down to the TextFormField. It auto-validates the field with the provided validators. Check TextFormField documentation for more details.	true
autovalidateMode	AutovalidateMode	This is passed down to underlying TextFormField. However this is by default to set to AutovalidateMode.always to perform some default validations like min , max and incDecFactor based validations. This validation closely mimics html's <input type='number'> tag available in chrome.	AutovalidateMode.always
min	num	Minimum acceptable value for this numeric field. Note: No error message will be shown. To show error a validator can be used and the widget should wrapped in Form widget.	0
max	num	Maximum acceptable value for this numeric field. Note: No error message will be shown. To show error a validator can be used and the widget should wrapped in Form widget.	double.infinity
enableMinMaxClamping	bool	Clamp the values to either min or max depending on which value is exceeded. e.g if min is 3 and max is 5 and user enters 7 it will clamped to 5 and if user enters 1 it will be clamped to 3.	true
incDecFactor	num	Factor by which the increment or decrement should happen. e.g. setting it 0.5 increments/decrements the field value by 0.5. This also decides what are valid steps of increment or decrement starting from the min value.	1
initialValue	num	An initial value to be set to the field.	0
isInt	bool	A flag to indicate if the field only accepts integer values. To use double values set this field to false.	true
numberFieldDecoration	InputDecoration	This decoration will be used by the TextFormField to handle its decoration.	An InputDecoration with an OutlineInputBorder to create a circular border.
widgetContainerDecoration	Decoration	This is the decoration for the Container that wraps this widget.	A simple BoxDecoration with a circular border in Colors.bluegrey color.
enable	bool	Passed down to the enable attribute of TextFormField. Note, this also disables the inc/dec buttons to avoid accidental changes.	true
validator	FormFieldValidator	A validator function which accepts a string and performs some validation. This is called when this field is wrapped inside a Form widget and called during its validate cycle. The error message to be shown should be returned form this method.	A validator that parses the number into a int or double is enabled by default. Additionally it enables a min/max validator if enableMinMaxClamping is false.  Refer the API documentation for more details.
style	TextStyle	Passed down to the style attribute of TextFormField	null
fractionDigits	int	The number of digits after the decimal point. Used only if isInt is false.	2
incIcon	IconData	The icon to be used for the increment button.	Icons.arrow_drop_up
decIcon	IconData	The icon to be used for the decrement button.	Icons.arrow_drop_down
incIconDecoration	Decoration	Decoration for the Increment Icon	Defaults to a black border in the bottom  and/or top depending on the buttonArrangement.
decIconDecoration	Decoration	Decoration for the decrement Icon	Defaults to a black border in the bottom  and/or top depending on the buttonArrangement.
incIconColor	Color	Icon color to be used for Increment button.	Defaults to color defined in IconTheme
decIconColor	Color	Icon color to be used for Decrement button.	Defaults to color defined in IconTheme
incIconSize	double	Icon size to be used for Increment button.	Defaults to size defined in IconTheme
decIconSize	double	Icon size to be used for Decrement button.	Defaults to size defined in IconTheme
onIncrement	DiffIncDecCallBack	A call back function to be called on successful increment. This will not be called if the internal validators fail.	null
onDecrement	DiffIncDecCallBack	A call back function to be called on successful decrement. This will not be called if the internal validators fail.	null
onSubmitted	ValueCallBack	A call back function to be called on users action denoting completion of editing the value. e.g. pressing the tick mark button. This will not be called if the internal validators fail. If enableMinMaxClampling is true and the value is entered is out of the range min to max it is corrected to be equal to either min or max - depending on which side of the range was exceeded.	null
onChanged	ValueCallBack	A call back function to be called on users action editing the value. e.g. typing a new number. This will not be called if the internal validators fail. If enableMinMaxClampling is true and the value is entered is out of the range min to max it is corrected to be equal to either min or max - depending on which side of the range was exceeded.	null
scaleWidth	double	A scaling factor for the width of the widget.	1.0
scaleHeight	double	A scaling factor for the height of the widget.	1.0
separateIcons	bool	Show a transparent separator between the increment & decrement buttons.	false
incDecBgColor	Color	Background color of the increment decrement button. This is set to Colors.lightGreen for all the NumberInputPrefabbed widgets to capture users attention.	widget tonull