theme-switcher

@nativescript/theme-switcher

Contents

• Installation
• Usage
  • Register the Themes
  • Switch Themes
  • Switch multiple themes simultaneously
• API
  • initThemes()
  • switchTheme()
  • loadDefaultTheme()
• Demo App
• License

Installation

npm install @nativescript/theme-switcher

Usage

Register the Themes

Use the initThemes() function to register the themes to switch from.

Call this function in the app's app.ts or main.ts file, before the app starts.

import { initThemes, switchTheme } from '@nativescript/theme-switcher'


// first initialize the themes
initThemes({
    // default is optional - will be auto-applied after initializing (*)
    default: () => import('theme-loader!./themes/default.scss'),
    red: () => import('theme-loader!./themes/red.scss'),
    green: () => import('theme-loader!./themes/green.scss'),
})

Switch Themes

To switch themes, call the [switchTheme()] method passing it the name of the theme to switch to.

switchTheme('red');
switchTheme('green');

Note: The theme-loader! prefix is used to apply a custom loader that prevents the styles from being auto-applied, and instead applied on-demand by the theme switcher. It requires @nativescript/webpack@5+ to work properly.

Note for TypeScript users: TypeScript does not know about theme-loader or css/scss files, in order to supress the type errors when calling import('theme-loader!./path/to/theme.css') you can add

/// <reference path="./node_modules/@nativescript/theme-switcher/shims.d.ts" />

To your references.d.ts, or use // @ts-ignore to supress the errors locally.

---

Switch multiple themes simultaneously

If you need to switch multiple themes simultaneously, you can initialize as many switchers as you need. Each switcher will load CSS and persist (unless disabled) the last selected theme.

Can be useful if your app can switch different parts of the theme individually. For example

1. switcher1 switches button styles
2. switcher2 switches font styles
3. etc.

import { ThemeSwitcher } from '@nativescript/theme-switcher'

const switcher1 = new ThemeSwitcher('switcher1');
const switcher2 = new ThemeSwitcher('switcher2');

switcher1.initThemes({ /* ... */})
switcher2.initThemes({ /* ... */})

switcher1.switchTheme( /* ... */ )
switcher2.switchTheme( /* ... */ )

API

initThemes()

initThemes(themes, options)

Register the themes to be switched from.

Parameter	Type	Description
themes	ThemeDefinition	An object with the theme name as the key, and a loader function that returns the theme css (css string, ast, optionally async). default will be applied initially, if set as a theme.
options	ThemeSwitcherOptions	Optional: Themes initialization settings.

ThemeDefinition

interface ThemeDefinition {
	[name: string]: () => any;
}

ThemeSwitcherOptions

Option	Type	Description
persistent	boolean	Optional: Defaults to true. If persistent is enabled, the last selected theme will be saved to ApplicationSettings and automatically restored when initThemes() is called.
persistenceKey	string	Optional: The key to the selected theme under on the device storage. Defaults to __theme_switcher_default

---

switchTheme()

switchTheme(themeName)

Used to switch from the current theme to the specified one.

Parameter	Type	Description
themeName	string	The name of the theme to switch to.

---

loadDefaultTheme()

import { loadDefaultTheme } from "@nativescript/theme-switcher"

loadDefaultTheme()

Loads the last selected theme if persistence is enabled, otherwise loads "default" if it exists.

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Demo App

Try out the plugin's demo with the NativeScript Preview app at StackBlitz.

License

Apache License Version 2.0