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Alert

website/versioned_docs/version-0.77/alert.md

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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

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import React from 'react';
import {StyleSheet, Button, Alert} from 'react-native';
import {SafeAreaView, SafeAreaProvider} from 'react-native-safe-area-context';

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

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 <div className="label android">Android</div>

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import React from 'react';
import {StyleSheet, Button, Alert} from 'react-native';
import {SafeAreaView, SafeAreaProvider} from 'react-native-safe-area-context';

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

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

export default App;

Reference

Methods

alert()

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

Parameters:

NameTypeDescription
title <div className="label basic required">Required</div>stringThe dialog's title. Passing null or empty string will hide the title.
messagestringAn optional message that appears below the dialog's title.
buttonsAlertButton[]An optional array containing buttons configuration.
optionsAlertOptionsAn optional Alert configuration.

prompt() <div className="label ios">iOS</div>

tsx
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:

NameTypeDescription
title <div className="label basic required">Required</div>stringThe dialog's title.
messagestringAn optional message that appears above the text input.
callbackOrButtonsfunction<hr/>AlertButton[]If passed a function, it will be called with the prompt's value
(text: string) => void, when the user taps 'OK'.<hr/>If passed an array, buttons will be configured based on the array content.
typeAlertTypeThis configures the text input.
defaultValuestringThe default text in text input.
keyboardTypestringThe keyboard type of first text field (if exists). One of TextInput keyboardTypes.
optionsAlertOptionsAn optional Alert configuration.

Type Definitions

AlertButtonStyle <div className="label ios">iOS</div>

An iOS Alert button style.

Type
enum

Constants:

ValueDescription
'default'Default button style.
'cancel'Cancel button style.
'destructive'Destructive button style.

AlertType <div className="label ios">iOS</div>

An iOS Alert type.

Type
enum

Constants:

ValueDescription
'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:

NameTypeDescription
textstringButton label.
onPressfunctionCallback function when button is pressed.
style <div className="label ios">iOS</div>AlertButtonStyleButton style, on Android this property will be ignored.
isPreferred <div className="label ios">iOS</div>booleanWhether button should be emphasized, on Android this property will be ignored.

AlertOptions

Type
object

Properties:

NameTypeDescription
cancelable <div className="label android">Android</div>booleanDefines if alert can be dismissed by tapping outside of the alert box.
userInterfaceStyle <div className="label ios">iOS</div>stringThe interface style used for the alert, can be set to light or dark, otherwise the default system style will be used.
onDismiss <div className="label android">Android</div>functionCallback function fired when alert has been dismissed.