title: How to arrange widgets in Stack
body: <p>When expanding the <code>DropdownButton</code> widget, when I want to scroll the dropdown list up or down, then my map in the background is scaled, and the dropdown list and the container with the <code>Авторизация</code> button have a transparency through which I can interact with the map (move, scale). Is it all about the Stack Widget? How to solve this problem?</p>
  <p>Dropdown list</p>
  <p><a href="https://i.stack.imgur.com/fiqRJ.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/fiqRJ.png" alt="dropdown list" /></a></p>
  <p>dropdown list when you scroll down (map scale changes)</p>
  <p><a href="https://i.stack.imgur.com/KSvie.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/KSvie.png" alt="dropdown list when you scroll down (map scale changes)" /></a></p>
  <p><strong><code>map_widget.dart</code></strong></p>
  <pre><code>return Stack(
        children: [
          _getMapWidget(),
          Align(
            alignment: Alignment.center,
            child: StreamBuilder&lt;MapState&gt;(
              initialData: _store.getInitialState(),
              stream: _store.getStateStream(),
              builder: (context, snapshot) {
                final state = snapshot.data!;
                if (state is MapStateLoading) {
                  return _Loading();
                } else if (state is MapStateContent) {
                  return SizedBox.shrink();
                } else if (state is MapStateError) {
                  return _Error();
                } else {
                  throw Exception('Unhandled state type :$state');
                }
              },
            ),
          ),
          Align(
            alignment: _cultureSelectionAlignment,
            child: Container(
              margin: EdgeInsets.all(12),
              padding: EdgeInsets.fromLTRB(12, 0, 12, 0),
              decoration: BoxDecoration(color: UiKitColors.white),
              child: _cultureWidgetFactory.create(
                (culture) =&gt; _store.process(
                  MapActionCultureClick(culture),
                ),
              ),
            ),
          ),
        ],
      );
  </code></pre>
  <p><strong><code>guest_widget.dart</code></strong></p>
  <pre><code>Widget _Body(BuildContext context) =&gt; Stack(
          children: [
            _mapWidgetBuilder(context),
            _SignIn(context),
          ],
        );
  
    Widget _SignIn(BuildContext context) =&gt; SafeArea(
          child: Align(
            alignment: Alignment.topCenter,
            child: Container(
              height: _signInContainerHeight,
              width: _signInContainerWidth,
              decoration: _SignInBackground(),
              child: Center(
                child: Column(
                  children: [
                    Padding(
                      padding: EdgeInsets.all(6),
                      child: Text(
                        _stringProvider.guestAuthorizationMessage,
                        textAlign: TextAlign.center,
                      ),
                    ),
                    _AuthButton(context),
                  ],
                ),
              ),
            ),
          ),
        );
  </code></pre>