Function startInputShims

core/src/utils/input-shims/input-shims.ts:16–142

(config: Config, platform: 'ios' | 'android')

const HIDE_CARET = true;

export const startInputShims = async (config: Config, platform: 'ios' | 'android') => {
  /**
   * If doc is undefined then we are in an SSR environment
   * where input shims do not apply.
   */
  if (doc === undefined) {
    return;
  }

  const isIOS = platform === 'ios';
  const isAndroid = platform === 'android';

  /**
   * Hide Caret and Input Blurring are needed on iOS.
   * Scroll Assist and Scroll Padding are needed on iOS and Android
   * with Chrome web browser (not Chrome webview).
   */
  const keyboardHeight = config.getNumber('keyboardHeight', 290);
  const scrollAssist = config.getBoolean('scrollAssist', true);
  const hideCaret = config.getBoolean('hideCaretOnScroll', isIOS);

  /**
   * The team is evaluating if inputBlurring is still needed. As a result
   * this feature is disabled by default as of Ionic 8.0. Developers are
   * able to re-enable it temporarily. The team may remove this utility
   * if it is determined that doing so would not bring any adverse side effects.
   * TODO FW-6014 remove input blurring utility (including implementation)
   */
  const inputBlurring = config.getBoolean('inputBlurring', false);
  const scrollPadding = config.getBoolean('scrollPadding', true);
  const inputs = Array.from(doc.querySelectorAll('ion-input, ion-textarea')) as HTMLElement[];

  const hideCaretMap = new WeakMap<HTMLElement, () => void>();
  const scrollAssistMap = new WeakMap<HTMLElement, () => void>();

  /**
   * Grab the native keyboard resize configuration
   * and pass it to scroll assist. Scroll assist requires
   * that we adjust the input right before the input
   * is about to be focused. If we called `Keyboard.getResizeMode`
   * on focusin in scroll assist, we could potentially adjust the
   * input too late since this call is async.
   */
  const keyboardResizeMode = await Keyboard.getResizeMode();

  const registerInput = async (componentEl: HTMLElement) => {
    await new Promise((resolve) => componentOnReady(componentEl, resolve));

    const inputRoot = componentEl.shadowRoot || componentEl;
    const inputEl = inputRoot.querySelector('input') || inputRoot.querySelector('textarea');
    const scrollEl = findClosestIonContent(componentEl);
    const footerEl = !scrollEl ? (componentEl.closest('ion-footer') as HTMLIonFooterElement | null) : null;

    if (!inputEl) {
      return;
    }

    if (HIDE_CARET && !!scrollEl && hideCaret && !hideCaretMap.has(componentEl)) {