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id title
alert
Alert

Launches an alert dialog with the specified title and message.

Optionally provide a list of buttons. Tapping any button will fire the respective onPress callback and dismiss the alert. By default, the only button will be an 'OK' button.

This is an API that works both on Android and iOS and can show static alerts. Alert that prompts the user to enter some information is available on iOS only.

Example

import React from 'react';
import {View, StyleSheet, Button, Alert} from 'react-native';

const App = () => {
  const createTwoButtonAlert = () =>
    Alert.alert('Alert Title', 'My Alert Msg', [
      {
        text: 'Cancel',
        onPress: () => console.log('Cancel Pressed'),
        style: 'cancel',
      },
      {text: 'OK', onPress: () => console.log('OK Pressed')},
    ]);

  const createThreeButtonAlert = () =>
    Alert.alert('Alert Title', 'My Alert Msg', [
      {
        text: 'Ask me later',
        onPress: () => console.log('Ask me later pressed'),
      },
      {
        text: 'Cancel',
        onPress: () => console.log('Cancel Pressed'),
        style: 'cancel',
      },
      {text: 'OK', onPress: () => console.log('OK Pressed')},
    ]);

  return (
    <View style={styles.container}>
      <Button title={'2-Button Alert'} onPress={createTwoButtonAlert} />
      <Button title={'3-Button Alert'} onPress={createThreeButtonAlert} />
    </View>
  );
};

const styles = StyleSheet.create({
  container: {
    flex: 1,
    justifyContent: 'space-around',
    alignItems: 'center',
  },
});

export default App;

iOS

On iOS you can specify any number of buttons. Each button can optionally specify a style or be emphasized, available options are represented by the AlertButtonStyle enum and the isPreferred field on AlertButton.

Android

On Android at most three buttons can be specified. Android has a concept of a neutral, negative and a positive button:

  • If you specify one button, it will be the 'positive' one (such as 'OK')
  • Two buttons mean 'negative', 'positive' (such as 'Cancel', 'OK')
  • Three buttons mean 'neutral', 'negative', 'positive' (such as 'Later', 'Cancel', 'OK')

Alerts on Android can be dismissed by tapping outside of the alert box. It is disabled by default and can be enabled by providing an optional AlertOptions parameter with the cancelable property set to true i.e.
{cancelable: true}.

The cancel event can be handled by providing an onDismiss callback property inside the options parameter.

Example
Android

import React from 'react';
import {View, StyleSheet, Button, Alert} from 'react-native';

const showAlert = () =>
  Alert.alert(
    'Alert Title',
    'My Alert Msg',
    [
      {
        text: 'Cancel',
        onPress: () => Alert.alert('Cancel Pressed'),
        style: 'cancel',
      },
    ],
    {
      cancelable: true,
      onDismiss: () =>
        Alert.alert(
          'This alert was dismissed by tapping outside of the alert dialog.',
        ),
    },
  );

const App = () => (
  <View style={styles.container}>
    <Button title="Show alert" onPress={showAlert} />
  </View>
);

const styles = StyleSheet.create({
  container: {
    flex: 1,
    justifyContent: 'center',
    alignItems: 'center',
  },
});

export default App;

Reference

Methods

alert()

static alert (
  title: string,
  message?: string,
  buttons?: AlertButton[],
  options?: AlertOptions,
);

Parameters:

Name Type Description
title
Required
string The dialog's title. Passing null or empty string will hide the title.
message string An optional message that appears below the dialog's title.
buttons AlertButton[] An optional array containing buttons configuration.
options AlertOptions An optional Alert configuration.

prompt()
iOS

static prompt: (
  title: string,
  message?: string,
  callbackOrButtons?: ((text: string) => void) | AlertButton[],
  type?: AlertType,
  defaultValue?: string,
  keyboardType?: string,
);

Create and display a prompt to enter some text in form of Alert.

Parameters:

Name Type Description
title
Required
string The dialog's title.
message string An optional message that appears above the text input.
callbackOrButtons function
AlertButton[]
If passed a function, it will be called with the prompt's value
(text: string) => void, when the user taps 'OK'.
If passed an array, buttons will be configured based on the array content.
type AlertType This configures the text input.
defaultValue string The default text in text input.
keyboardType string The keyboard type of first text field (if exists). One of TextInput keyboardTypes.
options AlertOptions An optional Alert configuration.

Type Definitions

AlertButtonStyle
iOS

An iOS Alert button style.

Type
enum

Constants:

Value Description
'default' Default button style.
'cancel' Cancel button style.
'destructive' Destructive button style.

AlertType
iOS

An iOS Alert type.

Type
enum

Constants:

Value Description
'default' Default alert with no inputs
'plain-text' Plain text input alert
'secure-text' Secure text input alert
'login-password' Login and password alert

AlertButton

An object describing the configuration of a button in the alert.

Type
array of objects

Objects properties:

Name Type Description
text string Button label.
onPress function Callback function when button is pressed.
style
iOS
AlertButtonStyle Button style, on Android this property will be ignored.
isPreferred
iOS
boolean Whether button should be emphasized, on Android this property will be ignored.

AlertOptions

Type
object

Properties:

Name Type Description
cancelable
Android
boolean Defines if alert can be dismissed by tapping outside of the alert box.
userInterfaceStyle
iOS
string The interface style used for the alert, can be set to light or dark, otherwise the default system style will be used.
onDismiss
Android
function Callback function fired when alert has been dismissed.