Stepper

The stepper control lets the user adjust a value by increasing and decreasing it in small steps. Steppers are used in situations where a user needs to adjust a value by a small amount.

Basic Usage

The following example will render a simple Stepper with a label.

HTML
<label>
    <input mbsc-stepper data-label="The label of the stepper" />
</label>

For being more informative a description and a color can also be passed to the switch.

HTML
<!-- Label and description for more info -->
<label>
    <input mbsc-stepper data-label="Childrens" data-description="Number of childrens." />
</label>

<!-- Different color steppers -->
<label>
    <input mbsc-stepper data-color="danger" data-label="Danger" />
</label>
<label>
    <input mbsc-stepper color="info" label="Info" />
</label>

Auto initialization

If the component is added later to the DOM, e.g. with an Ajax page load, a custom function named enhance needs to be called in order to initialize the dynamically added component. When the enhance function is called on a DOM element, all form elements will be initialized inside this element.

$.get('/myform', function (responseHtml) {
    var $page = $('#page');
    $page.html(responseHtml);
    mobiscroll.enhance($page[0]);
});

Passing options

All the options can be passed to the stepper via data- attributes with exceptions of the native input supported ones. The attributes that the native html input supports can be passed directly without the data- prefix. For example thevalue or the disabled attributes (and so on...).

In this example we pass the rtl and the disabled options:

HTML
<label>
    <input mbsc-stepper data-rtl="true" value="10" disabled data-label="This is Disabled" />
</label>

Change value programmatically

HTML
<label>
    <input id="my-stepper" value="5" mbsc-stepper data-label="Stepper value change" />
</label>
JS
// get the input element, the stepper was initialized on
const inputElement = $('#my-stepper');
// get the instance of the stepper component
const stepperInstance = mobiscroll.getInst(inputElement);

const changeValueState = stepperInstance.value; // get the value as a number value
stepperInstance.value = 15; // will change the stepper value

Disabled state

The underlying input's disabled attribute will be taken into account at initialization time. For example:

<!-- This will create a disabled stepper -->
<label>
    <input disabled mbsc-stepper data-label="Initially disabled" />
</label>

<!-- The following will not be disabled -->
<label>
    <input mbsc-stepper data-label="Initially not disabled" />
</label>

Changing options dynamically

The options of the stepper can be changed dynamically using the setOptions method on the instance itself, or the global setOptions method.
Here is an example on how to change the disabled option on stepper:

HTML
<label>
    <input id="my-stepper" disabled mbsc-stepper data-label="My stepper" />
</label>
JS
// get the input element, the stepper was initialized on
const inputElement = $('#my-stepper');
// get the instance of the stepper component
const stepperInstance = mobiscroll.getInst(inputElement);

// set the disabled setting to false
stepperInstance.setOptions({ disabled: false });

Options

Name Data attribute Type Default value Description
color data-color String undefined A predefined color to style the component.
Supported values are:
  • primary
  • secondary
  • success
  • danger
  • warning
  • info
  • dark
  • light
description data-description String undefined A description that shows up under the label of the component.
disabled data-disabled Boolean false Initial disabled state of the component.
label data-label String undefined Sets the label of component.
inputPosition data-input-position String center Specify the input field position. It can be "start", "end" or "center".
max data-max Number 100 Specify the maximum value that can be selected.
min data-min Number 0 Specify the minimum value that can be selected.
step data-step Number 1 Specify the step between values.
rtl data-rtl Boolean false Right to left display.
theme data-theme String undefined

Sets the visual appearance of the component.

If it is 'auto' or undefined, the theme will automatically be chosen based on the platform. If custom themes are also present, they will take precedence over the built in themes, e.g. if there's an iOS based custom theme, it will be chosen on the iOS platform instead of the default iOS theme.

Supplied themes:
  • 'ios' - iOS theme
  • 'material' - Material theme
  • 'windows' - Windows theme
It's possible to modify theme colors or create custom themes.
Make sure that the theme you set is included in the downloaded package.
themeVariant data-theme-variant String undefined

Controls which variant of the theme will be used (light or dark).

Possible values:
  • 'light' - Use the light variant of the theme.
  • 'dark' - Use the dark variant of the theme.
  • 'auto' or undefined - Detect the preferred system theme on devices where this is supported.

To use the option with custom themes, make sure to create two custom themes, where the dark version has the same name as the light one, suffixed with '-dark', e.g.: 'my-theme' and 'my-theme-dark'.

value data-value Number 0 Specify the value of the stepper.

Customizing the appearance

While the provided pre-built themes are enough in many use cases, most of the times on top of adapting to a specific platform, you'd also like to match a brand or color scheme. Mobiscroll provides various ways to achieve this:

Override the Sass Color Variables

A convenient way to customize the colors of the Mobiscroll components is to override the Sass color variables.

Let's say your branding uses a nice red accent color, and you'd like that color to appear on the Mobiscroll components as well, while still using platform specific themes (e.g. ios on iOS devices, material on Android devices, and mobiscroll on desktop). You can override the accent color for every theme:

$mbsc-ios-accent: #e61d2a;
$mbsc-material-accent: #e61d2a;
$mbsc-mobiscroll-accent: #e61d2a;

@import "~@mobiscroll/JQuery/dist/css/mobiscroll.jquery.scss"
It's important that you override the variables BEFORE the scss file import, otherwise it won't make any difference.
Here's a complete guide on how to set up Mobiscroll with SASS support

You can also customize the colors on many levels:

  1. Theme specific variables (ex. $mbsc-material-background, $mbsc-ios-dark-text) are applied to all components in a theme. Complete list of variables here.
  2. Component specific global variables (ex. $mbsc-card-background-light, $mbsc-listview-text-dark) are applied to all themes for a specific component.
  3. Component and theme specific variables (ex. $mbsc-ios-dark-form-background, $mbsc-material-input-text) are applied to a specific theme and a specific component.

Tree Shaking for styles

Tree shaking is a term commonly used in web development and particularly in JavaScript for unused code removal. Since websites are served (mostly) over the network, loading times depend on content size, so minification and unused content elimination plays a major role in making webapps fluid.

For the JavaScript part, popular frameworks already have the treeshaking built in, so the components that are not used will be left out from the built project.

Eliminating unused styles

In case of the styles, leaving out the unused rules is not as straight forward.
The overarching idea is that CSS selectors match elements in the DOM, and those elements in the DOM come from all sorts of places: your static templates, dynamic templates based on server-side state, and of course, JavaScript, which can manipulate the DOM in any way at all, including pull things from APIs and third parties.

Sass variables to the rescue

The Mobiscroll Library comes with a modular SASS bundle, that can be configured which component styles and which themes to leave in and out for the compiled css file.

Every component and theme has a SASS variable that can be turned on or off. If the variable is falsy the styles that it needs will not be added to the bundle.

Example on configuring the styles
// include the ios theme
$mbsc-ios-theme: true;

// include the components:
$mbsc-datepicker: true;
$mbsc-eventcalendar: true;
        
@import "@mobiscroll/jquery/dist/css/mobiscroll.modular.scss"

In the above example the styles needed for the eventcalendar and datepicker will be included and only for the ios theme. All other components (like select or grid-layout) and all other themes will be left out from the bundle.

It's important that you override the variables BEFORE the scss file import, otherwise it won't make any difference.

Here's the complete list of the components and themes that can be used:

Some components use others internally, so it might happen that even though you don't want to include some styles, they will still end up in your bundle.
For example if you don't want to include the form components (input, button, segmented, etc...), but you are using the select component, the styles for the mobiscroll buttons, will still be in, because of the dependency.