title: Flutter gesturedetector not working in stack widget
body: <p>I am using the <code>stack</code> widget to show the back arrow button on an image. And its showing but the problem is it's not tappable mean Gesturededector is not working on Stack.</p>
  
  <p>My code</p>
  
  <pre><code>  Stack(
        children: &lt;Widget&gt;[
  
          Container(
            height: height * 0.4,
            decoration: BoxDecoration(
              image: DecorationImage(
                image: AssetImage(
                  'assets/images/place2.jpg',
                ),
                fit: BoxFit.fill,
              ),
            ),
          ),
          GestureDetector(
            behavior: HitTestBehavior.translucent,
            onTap: () =&gt; print("first container"),
            child: Align(
              alignment: Alignment.topLeft,
              child: Container(
                margin: EdgeInsets.only(left: width * 0.03),
                padding: EdgeInsets.only(top: statusBarHeight * 2),
  
                child: Icon(
                  Icons.arrow_back_ios,
                  size: 25,
                  color: Colors.white,
                ),
              ),
            ),
          ),
  
          SingleChildScrollView(
            child: Padding(
              padding: EdgeInsets.only(top: height * 0.3),
              child: SingleChildScrollView(
                child: ClipRRect(
                  borderRadius: BorderRadius.only(
                      topRight: Radius.circular(30),
                      topLeft: Radius.circular(30)),
                  child: Container(
                    decoration: BoxDecoration(
                      color: Colors.white,
                    ),
                    child: Column(
                      mainAxisSize: MainAxisSize.min,
                      children: &lt;Widget&gt;[
                        SizedBox(
                          height: height * 0.05,
                        ),
                        Container(
                          width: width,
                          margin: EdgeInsets.only(left: width * 0.03),
                          child: Text(
                            'NYC Food Festival',
                            textAlign: TextAlign.left,
                            style: TextStyle(fontSize: 30),
                          ),
                        ),
                        SizedBox(
                          height: height * 0.02,
                        ),
                        Container(
                          margin: EdgeInsets.only(left: width * 0.03),
                          child: Row(
                            children: &lt;Widget&gt;[
                              Icon(
                                Icons.calendar_today,
                                size: 20,
                                color: Color(0xff808080),
                              ),
                              SizedBox(width: width * 0.02), // give it width
                              Column(
                                children: &lt;Widget&gt;[
                                  Text(
                                    'Sat, May 25, 2020',
                                    style: TextStyle(
                                        color: Color(0xff000000),
                                        fontWeight: FontWeight.bold,
                                        fontSize: 15),
                                  ),
                                ],
                              )
                            ],
                          ),
                        ),
                        SizedBox(
                          height: height * 0.02,
                        ),
                        Container(
                          margin: EdgeInsets.only(left: width * 0.03),
                          child: Row(
                            children: &lt;Widget&gt;[
                              Icon(
                                Icons.attach_money,
                                size: 20,
                                color: Color(0xff808080),
                              ),
                              SizedBox(width: width * 0.02), // give it width
                              Column(
                                children: &lt;Widget&gt;[
                                  Text(
                                    '25,000 PKR',
                                    style: TextStyle(
                                        color: Color(0xff000000),
                                        fontWeight: FontWeight.bold,
                                        fontSize: 15),
                                  ),
                                ],
                              )
                            ],
                          ),
                        ),
                        SizedBox(
                          height: height * 0.02,
                        ),
                        SizedBox(
                          height: height * 0.02,
                        ),
                        Container(
                          width: width,
                          margin: EdgeInsets.only(left: width * 0.03),
                          child: Text(
                            'Snaps',
                            textAlign: TextAlign.left,
                            style: TextStyle(fontSize: 25),
                          ),
                        ),
                        SizedBox(
                          height: height * 0.02,
                        ),
                        Container(
                            child: Column(
                              children: &lt;Widget&gt;[
                                CarouselSlider(
                                  options: CarouselOptions(
                                    autoPlay: true,
                                    aspectRatio: 2.0,
                                    enlargeCenterPage: true,
                                  ),
                                  items: imageSliders,
                                ),
                              ],
                            )),
                        SizedBox(
                          height: height * 0.02,
                        ),
                        Container(
                          width: width,
                          margin: EdgeInsets.only(left: width * 0.03),
                          child: Text(
                            'About',
                            textAlign: TextAlign.left,
                            style: TextStyle(fontSize: 25),
                          ),
                        ),
                        SizedBox(
                          height: height * 0.02,
                        ),
                        Container(
                            padding: EdgeInsets.only(
                                right: width * 0.03, left: width * 0.03),
                            child: DescriptionTextWidget(
                                text:
                                    "Flutter is Google’s mobile UI framework for crafting high-quality native interfaces on iOS and Android in record time. Flutter works with existing code, is used by developers and organizations around the world, and is free and open source.")
                        ),
                        SizedBox(
                          height: height * 0.02,
                        ),
                        Container(
                          width: width,
                          margin: EdgeInsets.only(left: width * 0.03),
                          child: Text(
                            'Included',
                            textAlign: TextAlign.left,
                            style: TextStyle(fontSize: 25),
                          ),
                        ),
                        SizedBox(
                          height: height * 0.02,
                        ),
                        Included(),
                        SizedBox(
                          height: height * 0.01,
                        ),
                        Included(),
                        SizedBox(
                          height: height * 0.01,
                        ),
                        Included(),
                        SizedBox(
                          height: height * 0.01,
                        ),
  
  
  
  
                      ],
                    ),
                  ),
                ),
              ),
            ),
          ),
          Positioned(
            bottom: 0,
            left: 0,
            right: 0,
            child: Container(
              height: 100,
              decoration: BoxDecoration(
                // color: Color.fromARGB(110, 255, 255, 255),
                borderRadius: BorderRadius.only(
                  topLeft: Radius.circular(20),
                  topRight: Radius.circular(20),
                ),
                gradient: LinearGradient(
                  colors: [
                    Color.fromARGB(30, 255, 255, 255),
                    Color.fromARGB(255, 255, 255, 255),
                  ],
                  begin: Alignment.topCenter,
                  end: Alignment.bottomCenter,
                ),
              ),
              child: Center(
                child: InkWell(
                  child: Container(
                    padding: EdgeInsets.symmetric(
                      horizontal: 80,
                      vertical: 20,
                    ),
                    decoration: BoxDecoration(
                      borderRadius: BorderRadius.circular(30),
                      color: Colors.blueAccent,
                    ),
                    child: Text(
                      "BOOK NOW",
                      style: TextStyle(
                          fontWeight: FontWeight.bold,
                          fontSize: 20,
                          color: Colors.white),
                    ),
                  ),
                  onTap: () {
                    return print("Tap");
                  },
                ),
              ),
            ),
          ),
        ],
      )
  </code></pre>
  
  <p>I need to use it as a back button when I navigate but it's not working then for testing I just print a value onTap but its also not working I try to add <code>behaviour</code> also.</p>