bootstrap-input-spinner

A Bootstrap 4 / jQuery plugin to create input spinner elements for number input.

Demo page with examples

Screenshot with floating point example and german localization.

Features

The Bootstrap 4 InputSpinner

• is mobile friendly and responsive,
• automatically changes the value when holding a button,
• has internationalized number formatting,
• allows setting a prefix or a suffix text in the input,
• handles val() like the native element,
• dynamically handles changing attribute values like disabled or class,
• dispatches change and input events on value change like the native element and
• works without extra css, only bootstrap 4 is needed.

Installation

npm install bootstrap-input-spinner

Or just download the GitHub repository and include src/bootstrap-input-spinner.js.

Usage

HTML

Create the element in HTML. The attributes are compatible to the native input[type="number"] element.

<input type="number" value="50" min="0" max="100" step="10"/>

Script

It is a jQuery plugin. So, enable the InputSpinner for all inputs with type='number' with the following script.

<script src="./src/bootstrap-input-spinner.js"></script>
<script>
    $("input[type='number']").inputSpinner();
</script>

Thats it. No extra css needed, just Bootstrap 4 and jQuery.

Syntax and configuration

HTML

<input type="number" value="4.5" min="0" max="9" step="0.1" data-decimals="2" data-suffix="°C"/>

Use these attributes to configure the behaviour

• value // starting value on element creation
• min // minimum value when stepping
• max // maximum value when stepping
• step // step size
• inputmode // the "inputmode" of the input, defaults to "decimal" (shows decimal keyboard on touch devices)
• data-decimals // shown decimal places
• data-digit-grouping // "false" to disable grouping (thousands separator), default is "true"
• data-prefix // show a prefix text in the input element
• data-suffix // show a suffix text in the input element

The InputSpinner also handles the standard input attributes required, disabled, readonly and placeholder.

JavaScript

Use JavaScript to create the instance as a jQuery plugin. You may provide additional configuration in an object as a config parameter.

$(element).inputSpinner(config);

Configuration

The default configuration is

var props = {
    decrementButton: "<strong>&minus;</strong>", // button text
    incrementButton: "<strong>&plus;</strong>", // ..
    groupClass: "", // css class of the resulting input-group
    buttonsClass: "btn-outline-secondary",
    buttonsWidth: "2.5rem",
    textAlign: "center", // alignment of the entered number
    autoDelay: 500, // ms threshold before auto value change
    autoInterval: 50, // speed of auto value change
    buttonsOnly: false, // set this `true` to disable the possibility to enter or paste the number via keyboard
    keyboardStepping: true, // set this to `false` to disallow the use of the up and down arrow keys to step
    locale: navigator.language, // the locale, per default detected automatically from the browser
    template: // the template of the input
        '<div class="input-group ${groupClass}">' +
        '<div class="input-group-prepend"><button style="min-width: ${buttonsWidth}" class="btn btn-decrement ${buttonsClass} btn-minus" type="button">${decrementButton}</button></div>' +
        '<input type="text" inputmode="decimal" style="text-align: ${textAlign}" class="form-control form-control-text-input"/>' +
        '<div class="input-group-append"><button style="min-width: ${buttonsWidth}" class="btn btn-increment ${buttonsClass} btn-plus" type="button">${incrementButton}</button></div>' +
        '</div>'
}

decrementButton, incrementButton

HTML of the texts inside the buttons.

groupClass

Additional css class for the input-group, results in

<div class="input-group ${groupClass}">

buttonsClass

The css class of the buttons. Use it to style the increment and decrement buttons as described here. Maybe buttonsClass: btn-primary or btn-success or whatever type of buttons you want.

buttonsWidth

The width of the increment and decrement buttons.

textAlign

The text alignment inside the <input>

autoDelay

The delay in ms after which the input automatically changes the value, when holding the increment or decrement button.

autoInterval

Speed of the value change when holding the button in ms. A lower value makes it faster.

buttonsOnly

In buttonsOnly mode (set true) no direct text input is allowed, the text-input gets the attribute readonly. But the plus and minus buttons still allow to change the value.

keyboardStepping

In keyboardStepping mode (set true) allows the use of the up/down arrow keys to increase/decrease the number by the step.

locale

Used to format the number in the UI. Detected automatically from the users browser, can be set to "de", "en",… or "de_DE", "en_GB",….

Programmatic change and read of value

To change or read the value just use the jQuery val() function on the input, like this

var currentValue = $(element).val() // read
$(element).val(newValue) // write

Hint: Reading the value in vanilla JS with element.value will also work, but to set the value you have to use element.setValue(newValue) or $(element).val(newValue)

Handling attributes

The attributes min, max, step, decimals, placeholder, required, disabled, readonly and class are handled dynamically. The class attribute value is dynamically copied to the input element.

Sizing

If the original elements class is set to form-control-sm of form-control-lg the class of the resulting input-group is dynamically set to input-group-sm or input-group-lg.

Events

The InputSpinner handles input and change events like the native element.

Event handling with vanilla JavaScript

element.addEventListener("change", function(event) {
    newValue = this.value
})

Event handling with jQuery syntax

$(element).on("change", function (event) {
    newValue = $(this).val()
})

Methods

Methods are passed as string values instead of the options object.

destroy

Removes the InputSpinner and shows the original input element.

$(element).inputSpinner("destroy")

Minified version

I don't provide a minified version because I think it should be up to the using programmer to create minified versions, with all the used script sources concatenated to one file.

But, if you want it, it is easy to create your minified version with uglify: https://www.npmjs.com/package/uglify-js

Just install uglify

npm install uglify-js -g

and then in the src-folder

uglifyjs bootstrap-input-spinner.js --compress --mangle > bootstrap-input-spinner.min.js

Violà! :)

Browser support

The spinner works in all modern browsers and in the Internet Explorer. Not tested with IE < 11.

For older browsers (IE 9 or so), that doesn't support Intl, when you get an error message like "Intl is not defined" (See issue #34), just use a shim or polyfill like Intl.js, and it works.

Our further Bootstrap and HTML extensions

If you like this component, you may want to check out our other Bootstrap and HTML extensions bootstrap-show-modal, bootstrap-detect-breakpoint, auto-resize-textarea and external-links-blank.