title: fluttercandies extended_image. How do I zoom in on an image with double tap of 1 finger instead of needing 2?
body: <p><a href="https://github.com/fluttercandies/extended_image" rel="nofollow noreferrer">https://github.com/fluttercandies/extended_image</a></p>
  
  <p><a href="https://github.com/fluttercandies/extended_image/tree/master/example" rel="nofollow noreferrer">https://github.com/fluttercandies/extended_image/tree/master/example</a> </p>
  
  <p><a href="https://github.com/fluttercandies/extended_image/blob/master/example/lib/pages/zoom_image_demo.dart" rel="nofollow noreferrer">https://github.com/fluttercandies/extended_image/blob/master/example/lib/pages/zoom_image_demo.dart</a></p>
  
  <p>fluttercandies extended_image. How do I zoom in on an image with double tap of 1 finger instead of needing 2? How do I get a sliding image to navigator pop back when it slides off the page? </p>
  
  <p>Trying to implement a zoom/pan image with double tap by 1 finger instead of the need for 2 to expand zoom an image. Have two issues with this code and was wondering if anyone has any ideas. The class is very simple with just 2 strings: image &amp; title passed into it.</p>
  
  <p>1, I need the image to expand on double tap. I would like the user to have to power to expand the image with one finger and not two. Think I need to put this code near the very end.
  The good thing is that once it is expanded the double tap works to reduce the image size. How do I get it to do the opposite when it is at normal size?</p>
  
  <p>2, the sliding of the image off the page results in a black screen. Thankfully, this doesn’t freeze or crash the app but it leaves the user with a blank screen and the need to press the system back button. I would like the slide to result in a navigator pop back to the original screen. </p>
  
  <p>Firstly, here’s a sample code of how I’m passing an image and a title into expandimage.dart.</p>
  
  <pre><code>FlatButton(
              child: Image.asset(_kAsset5),
              onPressed: () async {
                Navigator.push(
                  context,
                  MaterialPageRoute(
                      builder: (context) =&gt; ExpandImage(
                            image: _kAsset5,
                            title: "\'go help\' 1",
                          )),
                );
              },
            ),
  </code></pre>
  
  <p>Here’s the code that I’m using for this ‘expandimage.dart’ and a lot of it is based on the pan/zoom example from flutter candies / extended image example. </p>
  
  <pre><code>import 'package:flutter/material.dart';
  import 'package:extended_image/extended_image.dart';
  
  class ExpandImage extends StatelessWidget {
    final String image, title;
  
    ExpandImage({this.image, this.title});
  
    @override
    Widget build(BuildContext context) {
      return MaterialApp(
        home: Scaffold(
          backgroundColor: Colors.red[900],
          appBar: AppBar(
            backgroundColor: Colors.red[900],
            leading: IconButton(
              icon: Icon(Icons.close),
              onPressed: Navigator.of(context).pop,
            ),
            title: Text(
              title,
              style: TextStyle(
                color: Colors.yellow,
                inherit: true,
                fontWeight: FontWeight.w300,
                fontStyle: FontStyle.italic,
                letterSpacing: 2.0, //1.2
              ),
            ),
            centerTitle: true,
          ),
          body: SizedBox.expand(
            // child: Hero(
            // tag: heroTag,
            child: ExtendedImageSlidePage(
              slideAxis: SlideAxis.both,
              slideType: SlideType.onlyImage,
              child: ExtendedImage(
                //disable to stop image sliding off page &amp;&amp; entering dead end without back button.
                //setting to false means it won't slide at all.
                enableSlideOutPage: true,
                mode: ExtendedImageMode.gesture,
                initGestureConfigHandler: (state) =&gt; GestureConfig(
                  minScale: 1.0,
                  animationMinScale: 0.8,
                  maxScale: 3.0,
                  animationMaxScale: 3.5,
                  speed: 1.0,
                  inertialSpeed: 100.0,
                  initialScale: 1.0,
                  inPageView: false,
                ),
                // onDoubleTap: ?  zoom in on image
                fit: BoxFit.scaleDown,
                image: AssetImage(
                  image,
                ),
              ),
            ),
          ),
        ),
      );
    }
  }
  </code></pre>
  
  <p>Here is a sample image passed in. the page turns red when sliding the image around and then it goes black as the image slides off the page.
  <a href="https://i.stack.imgur.com/BmyCr.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/BmyCr.png" alt="flutter extended_image"></a></p>