extended_image 0.3.6

extended official image with loading/failed state,cache network,zoom/pan,photo view,crop,save,clip,paint custom.

extended_image

extended official image to support placeholder(loading)/ failed state, cache network,zoom/pan,photo view,crop,save,clip,paint custom etc.

Chinese blog

cache network image

You can use ExtendedNetworkImageProvider

  ExtendedNetworkImageProvider(
     this.url, {
     this.scale = 1.0,
     this.headers,
     this.cache: false,
     this.retries = 3,
     this.timeLimit,
     this.timeRetry = const Duration(milliseconds: 100),
     CancellationToken cancelToken,
   })  : assert(url != null),
         assert(scale != null),
         cancelToken = cancelToken ?? CancellationToken();
 
   ///time Limit to request image
   final Duration timeLimit;
 
   ///the time to retry to request
   final int retries;
 
   ///the time duration to retry to request
   final Duration timeRetry;
 
   ///whether cache image to local
   final bool cache;
 
   /// The URL from which the image will be fetched.
   final String url;
 
   /// The scale to place in the [ImageInfo] object of the image.
   final double scale;
 
   /// The HTTP headers that will be used with [HttpClient.get] to fetch image from network.
   final Map<String, String> headers;
 
   ///token to cancel network request
   final CancellationToken cancelToken;

More: timeRetry/retries/timeLimit are used for request parameter

or just use with following code

ExtendedImage.network(
                url,
                width: ScreenUtil.instance.setWidth(400),
                height: ScreenUtil.instance.setWidth(400),
                fit: BoxFit.fill,
                cache: true,
                border: Border.all(color: Colors.red, width: 1.0),
                shape: boxShape,
                borderRadius: BorderRadius.all(Radius.circular(30.0)),
              ),

zoom/pan image

set mode=ExtendedImageMode.Gesture to enable zoom/pan image and set config with GestureConfig

ExtendedImage.network(
          imageTestUrl,
          fit: BoxFit.contain,
          //enableLoadState: false,
          mode: ExtendedImageMode.Gesture,
          gestureConfig: GestureConfig(
              minScale: 0.9,
              animationMinScale: 0.7,
              maxScale: 3.0,
              animationMaxScale: 3.5,
              speed: 1.0,
              inertialSpeed: 100.0,
              initialScale: 1.0,
              inPageView: false),
        )

photo view like WeChat

ExtendedImageGesturePageView is made for zoom/pan image in page view.

remember set inPageView true for GestureConfig

you can cache gesture state in page view,so that gesture state will not change when page is changed.

remember call clearGestureDetailsCache() method at the right time.(for example,page view page is disposed)

           ExtendedImageGesturePageView.builder(
              itemBuilder: (BuildContext context, int index) {
                var item = widget.pics[index].picUrl;
                Widget image = ExtendedImage.network(
                  item,
                  fit: BoxFit.contain,
                  mode: ExtendedImageMode.Gesture,
                  gestureConfig: GestureConfig(
                      inPageView: true, initialScale: 1.0,
                      //you can cache gesture state even though page view page change.
                      //remember call clearGestureDetailsCache() method at the right time.(for example,this page dispose)
                      cacheGesture: false
                  ),
                );
                image = Container(
                  child: image,
                  padding: EdgeInsets.all(5.0),
                );
                if (index == currentIndex) {
                  return Hero(
                    tag: item + index.toString(),
                    child: image,
                  );
                } else {
                  return image;
                }
              },
              itemCount: widget.pics.length,
              onPageChanged: (int index) {
                currentIndex = index;
                rebuild.add(index);
              },
              controller: PageController(
                initialPage: currentIndex,
              ),
              scrollDirection: Axis.horizontal,
            ),

circle/borderRadius/border

Circle/BorderRadius/Border are easy to be used.

ExtendedImage.network(
                url,
                width: ScreenUtil.instance.setWidth(400),
                height: ScreenUtil.instance.setWidth(400),
                fit: BoxFit.fill,
                cache: true,
                border: Border.all(color: Colors.red, width: 1.0),
                shape: boxShape,
                borderRadius: BorderRadius.all(Radius.circular(30.0)),
              ),

clear and save

Clear disk cached , you can set duration to clear expired images or clear all of them.

// Clear the disk cache directory then return if it succeed.
///  <param name="duration">timespan to compute whether file has expired or not</param>
Future<bool> clearDiskCachedImages({Duration duration}) 

///clear all of image in memory
 clearMemoryImageCache();

/// get ImageCache
 getMemoryImageCache() ;

Save with image_picker_saver

///save netwrok image to photo
Future<bool> saveNetworkImageToPhoto(String url, {bool useCache: true}) async {
  var data = await getNetworkImageData(url, useCache: useCache);
  var filePath = await ImagePickerSaver.saveFile(fileData: data);
  return filePath != null && filePath != "";
}

custom load state

/// custom load state widget if you want
final LoadStateChanged loadStateChanged;

provide LoadStateChanged function to build custom load widget, it's not just for network image, if your image need long to load, you can define your loading widget or crop your image at that moment. see custom image demo

 ExtendedImage.network(
                 url,
                 width: ScreenUtil.instance.setWidth(600),
                 height: ScreenUtil.instance.setWidth(400),
                 fit: BoxFit.fill,
                 cache: true,
                 loadStateChanged: (ExtendedImageState state) {
                   switch (state.extendedImageLoadState) {
                     case LoadState.loading:
                       _controller.reset();
                       return Image.asset(
                         "assets/loading.gif",
                         fit: BoxFit.fill,
                       );
                       break;
                     case LoadState.completed:
                       _controller.forward();
                       return FadeTransition(
                         opacity: _controller,
                         child: ExtendedRawImage(
                           image: state.extendedImageInfo?.image,
                           width: ScreenUtil.instance.setWidth(600),
                           height: ScreenUtil.instance.setWidth(400),
                         ),
                       );
                       break;
                     case LoadState.failed:
                       _controller.reset();
                       return GestureDetector(
                         child: Stack(
                           fit: StackFit.expand,
                           children: <Widget>[
                             Image.asset(
                               "assets/failed.jpg",
                               fit: BoxFit.fill,
                             ),
                             Positioned(
                               bottom: 0.0,
                               left: 0.0,
                               right: 0.0,
                               child: Text(
                                 "load image failed, click to reload",
                                 textAlign: TextAlign.center,
                               ),
                             )
                           ],
                         ),
                         onTap: () {
                           state.reLoadImage();
                         },
                       );
                       break;
                   }
                 },
               )

crop image

you can crop image with ExtendedRawImage, soureRect is which you want to show image rect. crop image demo

ExtendedRawImage(
       image: image,
       width: num400,
       height: num300,
       fit: BoxFit.fill,
       soucreRect: Rect.fromLTWH(
           (image.width - width) / 2.0, 0.0, width, image.height.toDouble()),
     )

paint any thing you want when image is ready

provide BeforePaintImage and AfterPaintImage, you will have the chance to paint thing you want. see paint image demo and push to refresh header which is used in crop image demo

ExtendedImage.network(
                url,
                width: ScreenUtil.instance.setWidth(400),
                height: ScreenUtil.instance.setWidth(400),
                fit: BoxFit.fill,
                cache: true,
                beforePaintImage: (Canvas canvas, Rect rect, ui.Image image) {
                  if (paintType == PaintType.ClipHeart) {
                    if (!rect.isEmpty) {
                      canvas.save();
                      canvas.clipPath(clipheart(rect, canvas));
                    }
                  }
                  return false;
                },
                afterPaintImage: (Canvas canvas, Rect rect, ui.Image image) {
                  if (paintType == PaintType.ClipHeart) {
                    if (!rect.isEmpty) canvas.restore();
                  } else if (paintType == PaintType.PaintHeart) {
                    canvas.drawPath(
                        clipheart(rect, canvas),
                        Paint()
                          ..colorFilter = ColorFilter.mode(
                              Color(0x55ea5504), BlendMode.srcIn)
                          ..isAntiAlias = false
                          ..filterQuality = FilterQuality.low);
                  }
                },
              )