Method focusInitialElement

src/cdk/a11y/focus-trap/focus-trap.ts:205–245

* Focuses the element that should be focused when the focus trap is initialized. * @returns Whether focus was moved successfully.

(options?: FocusOptions)

   * @returns Whether focus was moved successfully.
   */
  focusInitialElement(options?: FocusOptions): boolean {
    // Contains the deprecated version of selector, for temporary backwards comparability.
    const redirectToElement = this._element.querySelector(
      `[cdk-focus-initial], ` + `[cdkFocusInitial]`,
    ) as HTMLElement;

    if (redirectToElement) {
      // @breaking-change 8.0.0
      if (
        (typeof ngDevMode === 'undefined' || ngDevMode) &&
        redirectToElement.hasAttribute(`cdk-focus-initial`)
      ) {
        console.warn(
          `Found use of deprecated attribute 'cdk-focus-initial', ` +
            `use 'cdkFocusInitial' instead. The deprecated attribute ` +
            `will be removed in 8.0.0`,
          redirectToElement,
        );
      }

      // Warn the consumer if the element they've pointed to
      // isn't focusable, when not in production mode.
      if (
        (typeof ngDevMode === 'undefined' || ngDevMode) &&
        !this._checker.isFocusable(redirectToElement)
      ) {
        console.warn(`Element matching '[cdkFocusInitial]' is not focusable.`, redirectToElement);
      }

      if (!this._checker.isFocusable(redirectToElement)) {
        const focusableChild = this._getFirstTabbableElement(redirectToElement) as HTMLElement;
        focusableChild?.focus(options);
        return !!focusableChild;
      }

      redirectToElement.focus(options);
      return true;
    }

    return this.focusFirstTabbableElement(options);
  }

  /**
   * Focuses the first tabbable element within the focus trap region.