@react-navigation/stack/lib/module/utils/useKeyboardManager.js

Stack navigator component for iOS and Android with animated transitions and gestures

import * as React from 'react';
import { Keyboard, TextInput } from 'react-native';
export default function useKeyboardManager(isEnabled) {
  // Numeric id of the previously focused text input
  // When a gesture didn't change the tab, we can restore the focused input with this
  const previouslyFocusedTextInputRef = React.useRef(undefined);
  const startTimestampRef = React.useRef(0);
  const keyboardTimeoutRef = React.useRef();
  const clearKeyboardTimeout = React.useCallback(() => {
    if (keyboardTimeoutRef.current !== undefined) {
      clearTimeout(keyboardTimeoutRef.current);
      keyboardTimeoutRef.current = undefined;
    }
  }, []);
  const onPageChangeStart = React.useCallback(() => {
    if (!isEnabled()) {
      return;
    }
    clearKeyboardTimeout();
    const input = TextInput.State.currentlyFocusedInput();

    // When a page change begins, blur the currently focused input
    input === null || input === void 0 ? void 0 : input.blur();

    // Store the id of this input so we can refocus it if change was cancelled
    previouslyFocusedTextInputRef.current = input;

    // Store timestamp for touch start
    startTimestampRef.current = Date.now();
  }, [clearKeyboardTimeout, isEnabled]);
  const onPageChangeConfirm = React.useCallback(force => {
    if (!isEnabled()) {
      return;
    }
    clearKeyboardTimeout();
    if (force) {
      // Always dismiss input, even if we don't have a ref to it
      // We might not have the ref if onPageChangeStart was never called
      // This can happen if page change was not from a gesture
      Keyboard.dismiss();
    } else {
      const input = previouslyFocusedTextInputRef.current;

      // Dismiss the keyboard only if an input was a focused before
      // This makes sure we don't dismiss input on going back and focusing an input
      input === null || input === void 0 ? void 0 : input.blur();
    }

    // Cleanup the ID on successful page change
    previouslyFocusedTextInputRef.current = undefined;
  }, [clearKeyboardTimeout, isEnabled]);
  const onPageChangeCancel = React.useCallback(() => {
    if (!isEnabled()) {
      return;
    }
    clearKeyboardTimeout();

    // The page didn't change, we should restore the focus of text input
    const input = previouslyFocusedTextInputRef.current;
    if (input) {
      // If the interaction was super short we should make sure keyboard won't hide again.

      // Too fast input refocus will result only in keyboard flashing on screen and hiding right away.
      // During first ~100ms keyboard will be dismissed no matter what,
      // so we have to make sure it won't interrupt input refocus logic.
      // That's why when the interaction is shorter than 100ms we add delay so it won't hide once again.
      // Subtracting timestamps makes us sure the delay is executed only when needed.
      if (Date.now() - startTimestampRef.current < 100) {
        keyboardTimeoutRef.current = setTimeout(() => {
          input === null || input === void 0 ? void 0 : input.focus();
          previouslyFocusedTextInputRef.current = undefined;
        }, 100);
      } else {
        input === null || input === void 0 ? void 0 : input.focus();
        previouslyFocusedTextInputRef.current = undefined;
      }
    }
  }, [clearKeyboardTimeout, isEnabled]);
  React.useEffect(() => {
    return () => clearKeyboardTimeout();
  }, [clearKeyboardTimeout]);
  return {
    onPageChangeStart,
    onPageChangeConfirm,
    onPageChangeCancel
  };
}
//# sourceMappingURL=useKeyboardManager.js.map