You are viewing documentation for v14 alpha. This version is under active development and APIs may change.
  • 14.x

      • Fire Event API

      fireEvent

      Note

      For common events like press or type it's recommended to use User Event API as it offers more realistic event simulation by emitting a sequence of events with proper event objects that mimic React Native runtime behavior.

      Use Fire Event for cases not supported by User Event and for triggering event handlers on composite components.

      function fireEvent(element: HostElement, eventName: string, ...data: unknown[]): Promise<unknown>;

      The fireEvent API allows you to trigger all kinds of event handlers on both host and composite components. It will try to invoke a single event handler traversing the component tree bottom-up from passed element and trying to find enabled event handler named onXxx when xxx is the name of the event passed.

      Unlike User Event, this API does not automatically pass event object to event handler, this is responsibility of the user to construct such object.

      This function uses async act function internally to ensure all pending React updates are executed during event handling.

      import { render, screen, fireEvent } from '@testing-library/react-native';

test('fire changeText event', async () => {
  const onEventMock = jest.fn();
  await render(
    // MyComponent renders TextInput which has a placeholder 'Enter details'
    // and with `onChangeText` bound to handleChangeText
    <MyComponent handleChangeText={onEventMock} />
  );

  await fireEvent(screen.getByPlaceholderText('change'), 'onChangeText', 'ab');
  expect(onEventMock).toHaveBeenCalledWith('ab');
});
      Note

      fireEvent performs checks that should prevent events firing on disabled elements.

      An example using fireEvent with native events that aren't already aliased by the fireEvent api.

      import { TextInput, View } from 'react-native';
import { fireEvent, render, screen } from '@testing-library/react-native';

const onBlurMock = jest.fn();

await render(
  <View>
    <TextInput placeholder="my placeholder" onBlur={onBlurMock} />
  </View>
);

// you can omit the `on` prefix
await fireEvent(screen.getByPlaceholderText('my placeholder'), 'blur');

      FireEvent exposes convenience methods for common events like: press, changeText, scroll.

      fireEvent.press

      Note

      It is recommended to use the User Event press() helper instead as it offers more realistic simulation of press interaction, including pressable support.

      fireEvent.press: (
  element: HostElement,
  ...data: Array<any>,
) => Promise<unknown>

      Invokes press event handler on the element or parent element in the tree.

      import { View, Text, TouchableOpacity } from 'react-native';
import { render, screen, fireEvent } from '@testing-library/react-native';

const onPressMock = jest.fn();
const eventData = {
  nativeEvent: {
    pageX: 20,
    pageY: 30,
  },
};

await render(
  <View>
    <TouchableOpacity onPress={onPressMock}>
      <Text>Press me</Text>
    </TouchableOpacity>
  </View>
);

await fireEvent.press(screen.getByText('Press me'), eventData);
expect(onPressMock).toHaveBeenCalledWith(eventData);

      fireEvent.changeText

      Note

      It is recommended to use the User Event type() helper instead as it offers more realistic simulation of text change interaction, including key-by-key typing, element focus, and other editing events.

      fireEvent.changeText: (
  element: HostElement,
  ...data: Array<any>,
) => Promise<unknown>

      Invokes changeText event handler on the element or parent element in the tree.

      import { View, TextInput } from 'react-native';
import { render, screen, fireEvent } from '@testing-library/react-native';

const onChangeTextMock = jest.fn();
const CHANGE_TEXT = 'content';

await render(
  <View>
    <TextInput placeholder="Enter data" onChangeText={onChangeTextMock} />
  </View>
);

await fireEvent.changeText(screen.getByPlaceholderText('Enter data'), CHANGE_TEXT);

      fireEvent.scroll

      Note

      Prefer using user.scrollTo over fireEvent.scroll for ScrollView, FlatList, and SectionList components. User Event provides a more realistic event simulation based on React Native runtime behavior.

      fireEvent.scroll: (
  element: HostElement,
  ...data: Array<any>,
) => Promise<unknown>

      Invokes scroll event handler on the element or parent element in the tree.

      On a ScrollView

      import { ScrollView, Text } from 'react-native';
import { render, screen, fireEvent } from '@testing-library/react-native';

const onScrollMock = jest.fn();
const eventData = {
  nativeEvent: {
    contentOffset: {
      y: 200,
    },
  },
};

await render(
  <ScrollView testID="scroll-view" onScroll={onScrollMock}>
    <Text>Content</Text>
  </ScrollView>
);

await fireEvent.scroll(screen.getByTestId('scroll-view'), eventData);

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