title: Flutter dialog not showing
body: <p>This is my code, Here I am triggering the function <code>showDialog</code>, but that dosen't show any dialog.</p>
  <pre><code>Widget appbar(BuildContext context) {
    return PreferredSize(
      preferredSize: Size.fromHeight(59.0), //AppBar Height
      child: AppBar(
        centerTitle: true, //make icon on center
        leading: Builder(
          builder: (context) =&gt; IconButton(
              icon: SizedBox(
                  height: 32,
                  width: 32,
                  child: Image.asset('resources/icon/menu.png')),
              onPressed: () {
                if (_scaffoldBodyKey.currentState.isDrawerOpen == false) {
                  _scaffoldBodyKey.currentState.openDrawer();
                } else {
                  _scaffoldBodyKey.currentState.openEndDrawer();
                }
              }),
        ),
        title: SizedBox(
            height: 32, width: 32, child: Image.asset('resources/icon/icon.png')),
        actions: &lt;Widget&gt;[
          IconButton(
              icon: SizedBox(
                  height: 25,
                  width: 25,
                  child: Image.asset('resources/icon/more.png')),
              onPressed: () {
                showDialog(
                  context: context,
                  builder: (ctx) =&gt; AlertDialog(
                    title: Text('Sfee'),
                    content: Text(&quot;dddsscsdcscs&quot;),
                    actions: &lt;Widget&gt;[
                      Column(
                        children: [
                          FlatButton(
                            child: Text('Okay'),
                            onPressed: () {
                              Navigator.of(ctx).pop();
                            },
                            color: Theme.of(context).accentColor,
                            padding: EdgeInsets.all(6),
                          ),
                        ],
                      )
                    ],
                  ),
                );
              }),
        ],
      ),
    );
  </code></pre>