Application Settings

The application-settings module allows you to save and restore information related to your application.

Usage

Basic usage of the application-settings module in a component:

const appSettings = require("tns-core-modules/application-settings");


function onNavigatingTo(args) {
    appSettings.setBoolean("isTurnedOn", true);
    appSettings.setString("username", "Wolfgang");
    appSettings.setNumber("locationX", 54.321);

    const isTurnedOn = appSettings.getBoolean("isTurnedOn");
    const username = appSettings.getString("username");
    const locationX = appSettings.getNumber("locationX");

    // Will return "No string value" if there is no value for "noSuchKey"
    const someKey = appSettings.getString("noSuchKey", "No string value");

    // Will return false if there is no key with name "noSuchKey"
    const isKeExisting = appSettings.hasKey("noSuchKey");
}
exports.onNavigatingTo = onNavigatingTo;

function onClear() {
    // Removing a single entry via its key name
    appSettings.remove("isTurnedOn");

    // Clearing the whole application-settings for this app
    appSettings.clear();
}

import {
    getBoolean,
    setBoolean,
    getNumber,
    setNumber,
    getString,
    setString,
    hasKey,
    remove,
    clear
} from "tns-core-modules/application-settings";

export function onNavigatingTo(args) {
    setBoolean("isTurnedOn", true);
    setString("username", "Wolfgang");
    setNumber("locationX", 54.321);

    const isTurnedOn: boolean = getBoolean("isTurnedOn");
    const username: string = getString("username");
    const locationX: number = getNumber("locationX");

    // Will return "No string value" if there is no value for "noSuchKey"
    const someKey: string = getString("noSuchKey", "No string value");

    // Will return false if there is no key with name "noSuchKey"
    let isKeExisting: boolean = hasKey("noSuchKey");
}

function onClear() {
    // Removing a single entry via its key name
    remove("isTurnedOn");

    // Clearing the whole application-settings for this app
    clear();
}

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Demo Source

Methods

Name	Type	Description
`clear`	`void`	Removes all stored values.
`flush`	`boolean`	Flush all changes to disk synchronously. The return flag indicates if changes were saved successfully to disk.
`getAllKeys`	`Array<string>`	Array containing all stored keys
`getBoolean(key: string, deafaultValue?: boolean)`	`boolean`	Gets a value (if existing) for a key as a Boolean Object. A default value can be provided in case there is no existing value.
`getNumber(key: string, deafaultValue?: number)`	`number`	Gets a value (if existing) for a key as a Number Object. A default value can be provided in case there is no existing value
`getString(key: string, deafaultValue?: string)`	`string`	Gets a value (if existing) for a key as a String Object. A default value can be provided in case there is no existing value.
`hasKey(key: string)`	`boolean`	Checks whether such a key exists.
`remove`	`void`	Removes an entry by its key name.
`setBoolean(key: string, value: boolean)`	`void`	Sets a Boolean Object for a key.
`setNumber(key: string, value: number)`	`void`	Sets a Number Object for a key.
`setString(key: string, value: string)`	`void`	Sets a String Object for a key.

API References

Name	Type
tns-core-modules/application-settings	`Module`

Native Component

Android	iOS
android.content.SharedPreferences	NSUserDefaults

NativeScript Core

Application Settings

Usage

Methods

API References

Native Component