extended_image
Language: English| 中文简体
A powerful official extension library of images, which supports placeholder(loading)/ failed state, cache network, zoom pan image, photo view, slide-out page, editor (crop, rotate, flip), paint custom etc.
ExtendedImage is an third-party library that extends the functionality of Flutter's Image component. The main extended features are as follows:
Feature | ExtendedImage | Image |
---|---|---|
Cache network images locally and load from cache | Supported | Not supported |
Compression display | Supported, with additional options (compressionRatio and maxBytes) | Supported, with cacheHeight, cacheWidth |
Automatic release of image resources | Supported | Requires manual management |
Scaling mode | Supported | Not supported |
Editing mode | Supported | Not supported |
Drag-to-dismiss effect for images in a page transition | Supported | Not supported |
Table of contents
- extended_image
Import
- null-safety
environment:
sdk: '>=2.12.0 <3.0.0'
flutter: '>=2.0'
dependencies:
extended_image: ^4.0.0
- non-null-safety
1.22.6 to 2.0, Flutter Api has breaking change,please use non-null-safety if you under 1.22.6.
environment:
sdk: '>=2.6.0 <2.12.0'
flutter: '>1.17.0 <=1.22.6'
dependencies:
extended_image: ^3.0.0-non-null-safety
Cache Network
Simple use
You can use ExtendedImage.network
as Image Widget
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)),
//cancelToken: cancellationToken,
)
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();
parameter | description | default |
---|---|---|
url | The URL from which the image will be fetched. | required |
scale | The scale to place in the ImageInfo object of the image. | 1.0 |
headers | The HTTP headers that will be used with HttpClient.get to fetch image from network. | - |
cache | whether cache image to local | false |
retries | the time to retry to request | 3 |
timeLimit | time limit to request image | - |
timeRetry | the time duration to retry to request | milliseconds: 100 |
cancelToken | token to cancel network request | CancellationToken() |
you can create new provider and extends it with ExtendedProvider, and override instantiateImageCodec method. so that you can handle image raw data here (compress image).
Load State
Extended Image provide 3 states(loading,completed,failed), you can define your state widget with loadStateChanged call back.
loadStateChanged is not only for network, if your image need long time to load, you can set enableLoadState(default value is true for network and others are false) to true
Notice:
-
if you don't want to override any state, please return null in this case
-
if you want to override size or sourceRect, you can override it with ExtendedRawImage at completed state
-
if you want to add something (like animation) at completed state, you can override it with ExtendedImageState.completedWidget
-
ExtendedImageState.completedWidget is include gesture or editor, so that you would't miss them
/// custom load state widget if you want
final LoadStateChanged loadStateChanged;
enum LoadState {
//loading
loading,
//completed
completed,
//failed
failed
}
///whether has loading or failed state
///default is false
///but network image is true
///better to set it's true when your image is big and take some time to ready
final bool enableLoadState;
ExtendedImageState(LoadStateChanged call back)
parameter/method | description | default |
---|---|---|
extendedImageInfo | image info | - |
extendedImageLoadState | LoadState(loading,completed,failed) | - |
returnLoadStateChangedWidget | if this is true, return widget which from LoadStateChanged function immediately(width/height/gesture/border/shape etc, will not effect on it) | - |
imageProvider | ImageProvider | - |
invertColors | invertColors | - |
imageStreamKey | key of image | - |
reLoadImage() | if image load failed,you can reload image by call it | - |
completedWidget | return completed widget include gesture or editor | - |
loadingProgress | return the loading progress for network image (ImageChunkEvent ) | - |
abstract class ExtendedImageState {
void reLoadImage();
ImageInfo get extendedImageInfo;
LoadState get extendedImageLoadState;
///return widget which from LoadStateChanged function immediately
bool returnLoadStateChangedWidget;
ImageProvider get imageProvider;
bool get invertColors;
Object get imageStreamKey;
Widget get completedWidget;
}
demo code
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;
///if you don't want override completed widget
///please return null or state.completedWidget
//return null;
//return state.completedWidget;
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;
}
},
)
Zoom Pan
ExtendedImage
parameter | description | default |
---|---|---|
mode | image mode (none, gesture, editor) | none |
initGestureConfigHandler | init GestureConfig when image is ready,for example, base on image width/height | - |
onDoubleTap | call back of double tap under ExtendedImageMode.gesture | - |
extendedImageGestureKey | you can handle zoom/pan by using this key manually | - |
GestureConfig
parameter | description | default |
---|---|---|
minScale | min scale | 0.8 |
animationMinScale | the min scale for zooming then animation back to minScale when scale end | minScale _ 0.8 |
maxScale | max scale | 5.0 |
animationMaxScale | the max scale for zooming then animation back to maxScale when scale end | maxScale _ 1.2 |
speed | speed for zoom/pan | 1.0 |
inertialSpeed | inertial speed for zoom/pan | 100 |
cacheGesture | save Gesture state (for example in ExtendedImageGesturePageView, gesture state will not change when scroll back),remember clearGestureDetailsCache at right time | false |
inPageView | whether in ExtendedImageGesturePageView | false |
initialAlignment | init image rect with alignment when initialScale > 1.0 | InitialAlignment.center |
hitTestBehavior | How to behave during hit tests | HitTestBehavior.deferToChild |
ExtendedImage.network(
imageTestUrl,
fit: BoxFit.contain,
//enableLoadState: false,
mode: ExtendedImageMode.gesture,
initGestureConfigHandler: (state) {
return GestureConfig(
minScale: 0.9,
animationMinScale: 0.7,
maxScale: 3.0,
animationMaxScale: 3.5,
speed: 1.0,
inertialSpeed: 100.0,
initialScale: 1.0,
inPageView: false,
initialAlignment: InitialAlignment.center,
);
},
)
double tap animation
onDoubleTap: (ExtendedImageGestureState state) {
///you can use define pointerDownPosition as you can,
///default value is double tap pointer down postion.
var pointerDownPosition = state.pointerDownPosition;
double begin = state.gestureDetails.totalScale;
double end;
//remove old
_animation?.removeListener(animationListener);
//stop pre
_animationController.stop();
//reset to use
_animationController.reset();
if (begin == doubleTapScales[0]) {
end = doubleTapScales[1];
} else {
end = doubleTapScales[0];
}
animationListener = () {
//print(_animation.value);
state.handleDoubleTap(
scale: _animation.value,
doubleTapPosition: pointerDownPosition);
};
_animation = _animationController
.drive(Tween<double>(begin: begin, end: end));
_animation.addListener(animationListener);
_animationController.forward();
},
Editor
ExtendedImage.network(
imageTestUrl,
fit: BoxFit.contain,
mode: ExtendedImageMode.editor,
initEditorConfigHandler: (state) {
return EditorConfig(
maxScale: 8.0,
cropRectPadding: EdgeInsets.all(20.0),
hitTestSize: 20.0,
cropAspectRatio: _aspectRatio.aspectRatio,
);
},
);
ExtendedImage
parameter | description | default |
---|---|---|
mode | image mode (none,gestrue,editor) | none |
initEditorConfigHandler | init EditorConfig when image is ready. | - |
extendedImageEditorKey | key of ExtendedImageEditorState to flip/rotate/get crop rect | - |
EditorConfig
parameter | description | default |
---|---|---|
maxScale | max scale of zoom | 5.0 |
cropRectPadding | the padding between crop rect and image layout rect. | EdgeInsets.all(20.0) |
cornerSize | size of corner shape (DEPRECATED! Use cornerPainter) | Size(30.0, 5.0) |
cornerColor | color of corner shape (DEPRECATED! Use cornerPainter) | primaryColor |
lineColor | color of crop line | scaffoldBackgroundColor.withOpacity(0.7) |
lineHeight | height of crop line | 0.6 |
editorMaskColorHandler | call back of editor mask color base on pointerDown | scaffoldBackgroundColor.withOpacity(pointerDown ? 0.4 : 0.8) |
hitTestSize | hit test region of corner and line | 20.0 |
animationDuration | auto center animation duration | Duration(milliseconds: 200) |
tickerDuration | duration to begin auto center animation after crop rect is changed | Duration(milliseconds: 400) |
cropAspectRatio | aspect ratio of crop rect | null(custom) |
initialCropAspectRatio | initial aspect ratio of crop rect | null(custom: initial crop rect will fill the entire image) |
initCropRectType | init crop rect base on initial image rect or image layout rect | imageRect |
cornerPainter | corner shape | ExtendedImageCropLayerPainterNinetyDegreesCorner() |
hitTestBehavior | How to behave during hit tests | HitTestBehavior.deferToChild |
controller | providing functions like rotating, flipping, undoing, redoing and reset actions. | null |
crop aspect ratio
it's a double value, so it's easy for you to define by yourself. following are official values
class CropAspectRatios {
/// no aspect ratio for crop
static const double custom = null;
/// the same as aspect ratio of image
/// [cropAspectRatio] is not more than 0.0, it's original
static const double original = 0.0;
/// ratio of width and height is 1 : 1
static const double ratio1_1 = 1.0;
/// ratio of width and height is 3 : 4
static const double ratio3_4 = 3.0 / 4.0;
/// ratio of width and height is 4 : 3
static const double ratio4_3 = 4.0 / 3.0;
/// ratio of width and height is 9 : 16
static const double ratio9_16 = 9.0 / 16.0;
/// ratio of width and height is 16 : 9
static const double ratio16_9 = 16.0 / 9.0;
}
crop layer painter
you can define your crop layer by override EditorConfig.editorCropLayerPainter
.
class EditorCropLayerPainter {
const EditorCropLayerPainter();
void paint(
Canvas canvas,
Size size,
ExtendedImageCropLayerPainter painter,
Rect rect,
) {
// Draw the mask layer
paintMask(canvas, rect, painter);
// Draw the grid lines
paintLines(canvas, size, painter);
// Draw the corners of the crop area
paintCorners(canvas, size, painter);
}
/// draw crop layer corners
void paintCorners(
Canvas canvas, Size size, ExtendedImageCropLayerPainter painter) {
}
/// draw crop layer lines
void paintMask(
Canvas canvas, Rect rect, ExtendedImageCropLayerPainter painter) {
}
/// draw crop layer lines
void paintLines(
Canvas canvas, Size size, ExtendedImageCropLayerPainter painter) {
}
}
flip, rotate, cropAspectRatio, undo ,redo , reset
ImageEditorController
final ImageEditorController _editorController = ImageEditorController();
initEditorConfigHandler: (ExtendedImageState? state) {
return EditorConfig(
maxScale: 4.0,
cropRectPadding: const EdgeInsets.all(20.0),
hitTestSize: 20.0,
initCropRectType: InitCropRectType.imageRect,
cropAspectRatio: CropAspectRatios.ratio4_3,
controller: _editorController,
);
},
flip
_editorController.flip();
void flip({
bool animation = false,
Duration duration = const Duration(milliseconds: 200),
})
rotate
_editorController.rotate();
void rotate({
double degrees = 90,
bool animation = false,
Duration duration = const Duration(milliseconds: 200),
bool rotateCropRect = true,
})
cropAspectRatio
_editorController.updateCropAspectRatio(CropAspectRatios.ratio4_3);
undo
bool canUndo = _editorController.canUndo;
_editorController.undo();
redo
bool canRedo = _editorController.canRedo;
_editorController.redo();
reset
_editorController.reset();
history
_editorController.currentIndex;
_editorController.history;
_editorController.saveCurrentState();
update config
_editorController.updateConfig(EditorConfig config);
_editorController.config;
crop data
dart library(stable)
- add Image library into your pubspec.yaml, it's used to crop/rotate/flip image data
dependencies:
image: any
- get crop rect and raw image data from ExtendedImageEditorState
///crop rect base on raw image
final Rect cropRect = state.getCropRect();
var data = state.rawImageData;
- convert raw image data to image library data.
/// it costs much time and blocks ui.
//Image src = decodeImage(data);
/// it will not block ui with using isolate.
//Image src = await compute(decodeImage, data);
//Image src = await isolateDecodeImage(data);
final lb = await loadBalancer;
Image src = await lb.run<Image, List<int>>(decodeImage, data);
- crop,flip,rotate data
//clear orientation
image = bakeOrientation(image);
if (editAction.hasRotateDegrees) {
image = copyRotate(image, angle: editAction.rotateDegrees);
}
if (editAction.flipY) {
image = flip(image, direction: FlipDirection.horizontal);
}
if (editAction.needCrop) {
image = copyCrop(
image,
x: cropRect.left.toInt(),
y: cropRect.top.toInt(),
width: cropRect.width.toInt(),
height: cropRect.height.toInt(),
);
}
- convert to original image data
output is raw image data, you can use it to save or any other thing.
/// you can encode your image
///
/// it costs much time and blocks ui.
//var fileData = encodeJpg(src);
/// it will not block ui with using isolate.
//var fileData = await compute(encodeJpg, src);
//var fileData = await isolateEncodeImage(src);
var fileData = await lb.run<List<int>, Image>(encodeJpg, src);
native library(faster)
- add ImageEditor library into your pubspec.yaml, it's used to crop/rotate/flip image data
dependencies:
image_editor: any
- get crop rect and raw image data from ExtendedImageEditorState
///crop rect base on raw image
final Rect cropRect = state.getCropRect();
var data = state.rawImageData;
- prepare crop option
if (action.hasRotateDegrees) {
final int rotateDegrees = action.rotateDegrees.toInt();
option.addOption(RotateOption(rotateDegrees));
}
if (action.flipY) {
option.addOption(const FlipOption(horizontal: true, vertical: false));
}
if (action.needCrop) {
Rect cropRect = imageEditorController.getCropRect()!;
option.addOption(ClipOption.fromRect(cropRect));
}
- crop with editImage
output is raw image data, you can use it to save or any other thing.
final result = await ImageEditor.editImage(
image: img,
imageEditorOption: option,
);
Photo View
ExtendedImageGesturePageView is the same as PageView and it's made for show zoom/pan image.
if you have cache the gesture, remember call clearGestureDetailsCache() method at the right time.(for example,page view page is disposed)
ExtendedImageGesturePageView
parameter | description | default |
---|---|---|
cacheGesture | whether should move page | true |
GestureConfig
parameter | description | default |
---|---|---|
cacheGesture | save Gesture state (for example in ExtendedImageGesturePageView, gesture state will not change when scroll back),remember clearGestureDetailsCache at right time | false |
inPageView | whether in ExtendedImageGesturePageView | false |
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,
),
Slide Out Page
Extended Image support to slide out page as WeChat.
enable slide out page
ExtendedImage
parameter | description | default |
---|---|---|
enableSlideOutPage | whether enable slide out page | false |
heroBuilderForSlidingPage | build Hero only for sliding page, the transform of sliding page must be working on Hero,so that Hero animation wouldn't be strange when pop page | null |
include your page in ExtendedImageSlidePage
take care of onSlidingPage call back, you can update other widgets' state as you want. but, do not setState directly here, image state will changed, you should only notify the widgets which are needed to change
return ExtendedImageSlidePage(
child: result,
slideAxis: SlideAxis.both,
slideType: SlideType.onlyImage,
onSlidingPage: (state) {
///you can change other widgets' state on page as you want
///base on offset/isSliding etc
//var offset= state.offset;
var showSwiper = !state.isSliding;
if (showSwiper != _showSwiper) {
// do not setState directly here, the image state will change,
// you should only notify the widgets which are needed to change
// setState(() {
// _showSwiper = showSwiper;
// });
_showSwiper = showSwiper;
rebuildSwiper.add(_showSwiper);
}
},
);
ExtendedImageGesturePage
parameter | description | default |
---|---|---|
child | The child contained by the ExtendedImageGesturePage. |
- |
slidePageBackgroundHandler | build background when slide page | defaultSlidePageBackgroundHandler |
slideScaleHandler | customize scale of page when slide page | defaultSlideScaleHandler |
slideEndHandler | call back of slide end,decide whether pop page | defaultSlideEndHandler |
slideAxis | axis of slide(both,horizontal,vertical) | SlideAxis.both |
resetPageDuration | reset page position when slide end(not pop page) | milliseconds: 500 |
slideType | slide whole page or only image | SlideType.onlyImage |
onSlidingPage | call back when it's sliding page, change other widgets state on page as you want | - |
slideOffsetHandler | customize offset when slide page | - |
Color defaultSlidePageBackgroundHandler(
{Offset offset, Size pageSize, Color color, SlideAxis pageGestureAxis}) {
double opacity = 0.0;
if (pageGestureAxis == SlideAxis.both) {
opacity = offset.distance /
(Offset(pageSize.width, pageSize.height).distance / 2.0);
} else if (pageGestureAxis == SlideAxis.horizontal) {
opacity = offset.dx.abs() / (pageSize.width / 2.0);
} else if (pageGestureAxis == SlideAxis.vertical) {
opacity = offset.dy.abs() / (pageSize.height / 2.0);
}
return color.withOpacity(min(1.0, max(1.0 - opacity, 0.0)));
}
bool defaultSlideEndHandler(
{Offset offset, Size pageSize, SlideAxis pageGestureAxis}) {
if (pageGestureAxis == SlideAxis.both) {
return offset.distance >
Offset(pageSize.width, pageSize.height).distance / 3.5;
} else if (pageGestureAxis == SlideAxis.horizontal) {
return offset.dx.abs() > pageSize.width / 3.5;
} else if (pageGestureAxis == SlideAxis.vertical) {
return offset.dy.abs() > pageSize.height / 3.5;
}
return true;
}
double defaultSlideScaleHandler(
{Offset offset, Size pageSize, SlideAxis pageGestureAxis}) {
double scale = 0.0;
if (pageGestureAxis == SlideAxis.both) {
scale = offset.distance / Offset(pageSize.width, pageSize.height).distance;
} else if (pageGestureAxis == SlideAxis.horizontal) {
scale = offset.dx.abs() / (pageSize.width / 2.0);
} else if (pageGestureAxis == SlideAxis.vertical) {
scale = offset.dy.abs() / (pageSize.height / 2.0);
}
return max(1.0 - scale, 0.8);
}
make sure your page background is transparent
if you use ExtendedImageSlidePage and slideType =SlideType.onlyImage, make sure your page background is transparent
push with transparent page route
you should push page with TransparentMaterialPageRoute/TransparentCupertinoPageRoute
Navigator.push(
context,
Platform.isAndroid
? TransparentMaterialPageRoute(builder: (_) => page)
: TransparentCupertinoPageRoute(builder: (_) => page),
);
Border BorderRadius Shape
ExtendedImage
parameter | description | default |
---|---|---|
border | BoxShape.circle and BoxShape.rectangle,If this is BoxShape.circle then borderRadius is ignored. |
- |
borderRadius | If non-null, the corners of this box are rounded by this BorderRadius.,Applies only to boxes with rectangular shapes; ignored if shape is not BoxShape.rectangle. |
- |
shape | BoxShape.circle and BoxShape.rectangle,If this is BoxShape.circle then borderRadius is ignored. |
- |
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 Save
clear
to clear disk cached , call clearDiskCachedImages method.
// 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})
to clear disk cached with specific url, call clearDiskCachedImage method.
/// clear the disk cache image then return if it succeed.
/// <param name="url">clear specific one</param>
Future<bool> clearDiskCachedImage(String url) async {
get the local cached image file
Future<File> getCachedImageFile(String url) async {
to clear memory cache , call clearMemoryImageCache method.
///clear all of image in memory
clearMemoryImageCache();
/// get ImageCache
getMemoryImageCache() ;
save network
call saveNetworkImageToPhoto and save image with image_picker_saver
///save network 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 != "";
}
Show Crop Image
get your raw image by Load State
(#Load State), and crop image by sourceRect.
ExtendedRawImage sourceRect is which you want to show image rect.
ExtendedRawImage(
image: image,
width: num400,
height: num300,
fit: BoxFit.fill,
sourceRect: Rect.fromLTWH(
(image.width - width) / 2.0, 0.0, width, image.height.toDouble()),
)
Paint
provide BeforePaintImage and AfterPaintImage callback, you will have the chance to paint things you want.
ExtendedImage
parameter | description | default |
---|---|---|
beforePaintImage | you can paint anything if you want before paint image. | - |
afterPaintImage | you can paint anything if you want after paint image. | - |
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);
}
},
);
see paint image demo and push to refresh header which is used in crop image demo
Notch
By setting layoutInsets, you can ensure the image is positioned outside of obstructing elements such as the phone notch or home indicator if displayed in full screen. This will still allow the image margin to show underneath the notch if zoomed in.
ExtendedImage
parameter | description | default |
---|---|---|
layoutInsets | Amount to inset from the edge during image layout | EdgeInsets.zero |
ExtendedImage.network(
url,
fit: BoxFit.contain,
layoutInsets: MediaQuery.of(context).padding
);
MemoryUsage
You can reduce memory usage with following settings now.
- ExtendedResizeImage
parameter | description | default |
---|---|---|
ExtendedResizeImage.compressionRatio | The images size will resize to original * [compressionRatio].It's ExtendedResizeImage s first pick.The compressionRatio`s range is from 0.0 (exclusive), to 1.0 (exclusive). |
null |
ExtendedResizeImage.maxBytes | ExtendedResizeImage will compress the image to a size that is smaller than maxBytes . The default size is 50KB. It's actual bytes of Image, not decode bytes |
50 << 10 |
ExtendedResizeImage.width/ExtendedResizeImage.height | The width/height the image should decode to and cache. It's same as ResizeImage, | null |
ExtendedImage.network(
'imageUrl',
compressionRatio: 0.1,
maxBytes: null,
cacheWidth: null,
cacheHeight: null,
)
ExtendedImage(
image: ExtendedResizeImage(
ExtendedNetworkImageProvider(
'imageUrl',
),
compressionRatio: 0.1,
maxBytes: null,
width: null,
height: null,
),
)
- clearMemoryCacheWhenDispose
parameter | description | default |
---|---|---|
clearMemoryCacheWhenDispose | It's not good enough after Flutter 2.0, it seems that we can't release memory usage if this image is not completed(https://github.com/fluttercandies/extended_image/issues/317). It will release memory usage only for completed image now. | false |
ExtendedImage.network(
'imageUrl',
clearMemoryCacheWhenDispose: true,
)
- imageCacheName
parameter | description | default |
---|---|---|
imageCacheName | The name of ImageCache, you can define custom ImageCache to store this image. In this way you can work with them without affecting other ImageCache | null |
ExtendedImage.network(
'imageUrl',
imageCacheName: 'MemoryUsage',
)
/// clear when this page is disposed
@override
void dispose() {
// clear ImageCache which named 'MemoryUsage'
clearMemoryImageCache(imageCacheName);
super.dispose();
}
Other APIs
ExtendedImage
parameter | description | default |
---|---|---|
enableMemoryCache | whether cache in PaintingBinding.instance.imageCache) | true |
clearMemoryCacheIfFailed | when failed to load image, whether clear memory cache.if true, image will reload in next time. | true |
clearMemoryCacheWhenDispose | when image is removed from the tree permanently, whether clear memory cache. | false |