Add support for invisible widgets

README.md

-# screenshot
+ <img src="https://github.com/SachinGanesh/screenshot/raw/master/assets/sc.png" alt="screenshot"/>
 
-A simple plugin to capture widgets as Images.
+A simple package to capture widgets as Images. Now you can capture widgets that are not rendered on the screen!
 
-This plugin wraps your widgets inside [RenderRepaintBoundary](https://docs.flutter.io/flutter/rendering/RenderRepaintBoundary-class.html)
+This package wraps your widgets inside [RenderRepaintBoundary](https://docs.flutter.io/flutter/rendering/RenderRepaintBoundary-class.html)
 
 [Source](https://stackoverflow.com/a/51118088)
 
+ <img src="https://github.com/SachinGanesh/screenshot/raw/master/assets/screenshot.gif" alt="screenshot" width="200"/>
+
+---
 ## Getting Started
 
-This handy plugin can be used to capture any Widget including full screen screenshots & individual widgets like Text().
+This handy package can be used to capture any Widget including full screen screenshots & individual widgets like Text().
 
 1) Create Instance of Screenshot Controller
 
@@ -49,7 +52,27 @@ screenshotController.capture().then((Uint8List image) {
     print(onError);
 });
 ```
+---
+## Capturing Widgets that are not in the widget tree
 
+You can capture invisible widgets by pr
+
+```dart
+screenshotController
+      .captureFromWidget(Container(
+          padding: const EdgeInsets.all(30.0),
+          decoration: BoxDecoration(
+            border:
+                Border.all(color: Colors.blueAccent, width: 5.0),
+            color: Colors.redAccent,
+          ),
+          child: Text("This is an invisible widget")))
+      .then((capturedImage) {
+    // Handle captured image
+  });
+},
+```
+---
 Example:
 
 ```dart
@@ -106,8 +129,9 @@ Example:
   }
 ```
 
- <img src="assets/screenshot.png" alt="screenshot" width="400"/>
+ <img src="https://github.com/SachinGanesh/screenshot/raw/master/assets/screenshot.png" alt="screenshot" width="400"/>
 
+---
 ## Saving images to Specific Location
 For this you can use captureAndSave method by passing directory location. By default, the captured image will be saved to Application Directory. Custom paths can be set using **path parameter**. Refer [path_provider](https://pub.dartlang.org/packages/path_provider)
 
@@ -126,20 +150,22 @@ screenshotController.captureAndSave(
     fileName:fileName 
 );
 ```
-
+---
 ## Saving images to Gallery
 If you want to save captured image to Gallery, Please use https://github.com/hui-z/image_gallery_saver
 Example app uses the same to save screenshots to gallery.
 
-## Note:
+### Note:
 Captured image may look pixelated. You can overcome this issue by setting value for **pixelRatio** 
 
 >The pixelRatio describes the scale between the logical pixels and the size of the output image. It is independent of the window.devicePixelRatio for the device, so specifying 1.0 (the default) will give you a 1:1 mapping between logical pixels and the output pixels in the image.
 
 
 ```dart
+double pixelRatio = MediaQuery.of(context).devicePixelRatio;
+
 screenshotController.capture(
-    pixelRatio: 1.5
+    pixelRatio: pixelRatio
 )
 ```
 ---
@@ -156,6 +182,6 @@ The solution is to add a small delay before capturing.
 screenshotController.capture(delay: Duration(milliseconds: 10))
 ```
 
-## Known Bugs
-- Image will not be updated if same filename is given multiple times
+## Known Issues
+- Platform Views are not supported. (Example: Google Maps, Camera etc)
 

example/ios/Podfile

@@ -10,62 +10,29 @@ project 'Runner', {
   'Release' => :release,
 }
 
-def parse_KV_file(file, separator='=')
-  file_abs_path = File.expand_path(file)
-  if !File.exists? file_abs_path
-    return [];
+def flutter_root
+  generated_xcode_build_settings_path = File.expand_path(File.join('..', 'Flutter', 'Generated.xcconfig'), __FILE__)
+  unless File.exist?(generated_xcode_build_settings_path)
+    raise "#{generated_xcode_build_settings_path} must exist. If you're running pod install manually, make sure flutter pub get is executed first"
   end
-  pods_ary = []
-  skip_line_start_symbols = ["#", "/"]
-  File.foreach(file_abs_path) { |line|
-      next if skip_line_start_symbols.any? { |symbol| line =~ /^\s*#{symbol}/ }
-      plugin = line.split(pattern=separator)
-      if plugin.length == 2
-        podname = plugin[0].strip()
-        path = plugin[1].strip()
-        podpath = File.expand_path("#{path}", file_abs_path)
-        pods_ary.push({:name => podname, :path => podpath});
-      else
-        puts "Invalid plugin specification: #{line}"
-      end
-  }
-  return pods_ary
+
+  File.foreach(generated_xcode_build_settings_path) do |line|
+    matches = line.match(/FLUTTER_ROOT\=(.*)/)
+    return matches[1].strip if matches
+  end
+  raise "FLUTTER_ROOT not found in #{generated_xcode_build_settings_path}. Try deleting Generated.xcconfig, then run flutter pub get"
 end
 
-target 'Runner' do
-  use_frameworks!
-  # Prepare symlinks folder. We use symlinks to avoid having Podfile.lock
-  # referring to absolute paths on developers' machines.
-  system('rm -rf .symlinks')
-  system('mkdir -p .symlinks/plugins')
+require File.expand_path(File.join('packages', 'flutter_tools', 'bin', 'podhelper'), flutter_root)
 
-  # Flutter Pods
-  generated_xcode_build_settings = parse_KV_file('./Flutter/Generated.xcconfig')
-  if generated_xcode_build_settings.empty?
-    puts "Generated.xcconfig must exist. If you're running pod install manually, make sure flutter packages get is executed first."
-  end
-  generated_xcode_build_settings.map { |p|
-    if p[:name] == 'FLUTTER_FRAMEWORK_DIR'
-      symlink = File.join('.symlinks', 'flutter')
-      File.symlink(File.dirname(p[:path]), symlink)
-      pod 'Flutter', :path => File.join(symlink, File.basename(p[:path]))
-    end
-  }
+flutter_ios_podfile_setup
 
-  # Plugin Pods
-  plugin_pods = parse_KV_file('../.flutter-plugins')
-  plugin_pods.map { |p|
-    symlink = File.join('.symlinks', 'plugins', p[:name])
-    File.symlink(p[:path], symlink)
-    pod p[:name], :path => File.join(symlink, 'ios')
-  }
+target 'Runner' do
+  flutter_install_all_ios_pods File.dirname(File.realpath(__FILE__))
 end
 
 post_install do |installer|
   installer.pods_project.targets.each do |target|
-    target.build_configurations.each do |config|
-      config.build_settings['SWIFT_VERSION'] = '4.2'
-      config.build_settings['ENABLE_BITCODE'] = 'NO'
-    end
+    flutter_additional_ios_build_settings(target)
   end
 end

example/ios/Runner.xcodeproj/project.xcworkspace/contents.xcworkspacedata

@@ -2,6 +2,6 @@
 <Workspace
    version = "1.0">
    <FileRef
-      location = "group:Runner.xcodeproj">
+      location = "self:">
    </FileRef>
 </Workspace>

example/ios/Runner.xcworkspace/xcshareddata/WorkspaceSettings.xcsettings

-<?xml version="1.0" encoding="UTF-8"?>
-<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
-<plist version="1.0">
-<dict>
-	<key>BuildSystemType</key>
-	<string>Original</string>
-</dict>
-</plist>

example/lib/main.dart

@@ -32,16 +32,6 @@ class MyApp extends StatelessWidget {
 
 class MyHomePage extends StatefulWidget {
   MyHomePage({Key key, this.title}) : super(key: key);
-
-  // This widget is the home page of your application. It is stateful, meaning
-  // that it has a State object (defined below) that contains fields that affect
-  // how it looks.
-
-  // This class is the configuration for the state. It holds the values (in this
-  // case the title) provided by the parent (in this case the App widget) and
-  // used by the build method of the State. Fields in a Widget subclass are
-  // always marked "final".
-
   final String title;
 
   @override
@@ -49,9 +39,6 @@ class MyHomePage extends StatefulWidget {
 }
 
 class _MyHomePageState extends State<MyHomePage> {
-  int _counter = 0;
-  Uint8List _imageFile;
-
   //Create an instance of ScreenshotController
   ScreenshotController screenshotController = ScreenshotController();
 
@@ -61,17 +48,6 @@ class _MyHomePageState extends State<MyHomePage> {
     super.initState();
   }
 
-  void _incrementCounter() {
-    setState(() {
-      // This call to setState tells the Flutter framework that something has
-      // changed in this State, which causes it to rerun the build method below
-      // so that the display can reflect the updated values. If we changed
-      // _counter without calling setState(), then the build method would not be
-      // called again, and so nothing would appear to happen.
-      _counter++;
-    });
-  }
-
   @override
   Widget build(BuildContext context) {
     // This method is rerun every time setState is called, for instance as done
@@ -86,43 +62,76 @@ class _MyHomePageState extends State<MyHomePage> {
         // the App.build method, and use it to set our appbar title.
         title: Text(widget.title),
       ),
-      body: Container(
-        child: new Center(
-          child: Screenshot(
-            controller: screenshotController,
-            child: Text("HEllo"),
-          ),
+      body: Center(
+        child: Column(
+          mainAxisAlignment: MainAxisAlignment.center,
+          children: [
+            Screenshot(
+              controller: screenshotController,
+              child: Container(
+                  padding: const EdgeInsets.all(30.0),
+                  decoration: BoxDecoration(
+                    border: Border.all(color: Colors.blueAccent, width: 5.0),
+                    color: Colors.amberAccent,
+                  ),
+                  child: Text("This widget will be captured as an image")),
+            ),
+            SizedBox(
+              height: 25,
+            ),
+            ElevatedButton(
+              child: Text(
+                'Capture Above Widget',
+              ),
+              onPressed: () {
+                screenshotController
+                    .capture(delay: Duration(milliseconds: 10))
+                    .then((Uint8List capturedImage) async {
+                  ShowCapturedWidget(context, capturedImage);
+                }).catchError((onError) {
+                  print(onError);
+                });
+              },
+            ),
+            ElevatedButton(
+              child: Text(
+                'Capture An Invisible Widget',
+              ),
+              onPressed: () {
+                screenshotController
+                    .captureFromWidget(Container(
+                        padding: const EdgeInsets.all(30.0),
+                        decoration: BoxDecoration(
+                          border:
+                              Border.all(color: Colors.blueAccent, width: 5.0),
+                          color: Colors.redAccent,
+                        ),
+                        child: Text("This is an invisible widget")))
+                    .then((capturedImage) {
+                  ShowCapturedWidget(context, capturedImage);
+                });
+              },
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+
+  Future<dynamic> ShowCapturedWidget(
+      BuildContext context, Uint8List capturedImage) {
+    return showDialog(
+      useSafeArea: false,
+      context: context,
+      builder: (context) => Scaffold(
+        appBar: AppBar(
+          title: Text("Captured widget screenshot"),
         ),
+        body: Center(
+            child: capturedImage != null
+                ? Image.memory(capturedImage)
+                : Container()),
       ),
-      floatingActionButton: FloatingActionButton(
-        onPressed: () {
-          _incrementCounter();
-          _imageFile = null;
-          screenshotController
-              .capture(delay: Duration(milliseconds: 10))
-              .then((Uint8List image) async {
-            _imageFile = image;
-            showDialog(
-              context: context,
-              builder: (context) => Scaffold(
-                appBar: AppBar(
-                  title: Text("CAPURED SCREENSHOT"),
-                ),
-                body: Center(
-                    child: Column(
-                  children: [
-                    _imageFile != null ? Image.memory(_imageFile) : Container(),
-                  ],
-                )),
-              ),
-            );
-          }).catchError((onError) {
-            print(onError);
-          });
-        },
-        tooltip: 'Increment',
-        child: Icon(Icons.add),
-      ), // This trailing comma makes auto-formatting nicer for build methods.
     );
   }
 

example/pubspec.yaml

@@ -8,6 +8,7 @@ description: A new Flutter project.
 # build by specifying --build-name and --build-number, respectively.
 # Read more about versioning at semver.org.
 version: 1.0.0+1
+publish_to: none
 
 environment:
   sdk: '>=2.8.0 <3.0.0'
@@ -19,7 +20,7 @@ dependencies:
   screenshot:
     path: ../
   cupertino_icons: ^0.1.2
-  image_gallery_saver: ^1.1.0
+  # image_gallery_saver: ^1.1.0
 
 dev_dependencies:
   flutter_test:

lib/screenshot.dart

@@ -21,7 +21,7 @@ class ScreenshotController {
     _containerKey = GlobalKey();
   }
 
-/// Captures image and saves to given path
+  /// Captures image and saves to given path
   Future<String> captureAndSave(
     String directory, {
     String? fileName,
@@ -49,8 +49,8 @@ class ScreenshotController {
           delay: Duration.zero,
           pixelRatio: pixelRatio,
         );
-        ByteData byteData =
-            await (image.toByteData(format: ui.ImageByteFormat.png) as FutureOr<ByteData>);
+        ByteData byteData = await (image.toByteData(
+            format: ui.ImageByteFormat.png) as FutureOr<ByteData>);
         Uint8List pngBytes = byteData.buffer.asUint8List();
 
         return pngBytes;
@@ -79,6 +79,59 @@ class ScreenshotController {
       }
     });
   }
+
+  Future<Uint8List> captureFromWidget(Widget widget,
+      {Duration delay: const Duration(milliseconds: 20)}) async {
+    final RenderRepaintBoundary repaintBoundary = RenderRepaintBoundary();
+
+    Size logicalSize = ui.window.physicalSize / ui.window.devicePixelRatio;
+    Size imageSize = ui.window.physicalSize;
+
+    assert(logicalSize.aspectRatio == imageSize.aspectRatio);
+
+    final RenderView renderView = RenderView(
+      window: ui.window,
+      child: RenderPositionedBox(
+          alignment: Alignment.center, child: repaintBoundary),
+      configuration: ViewConfiguration(
+        size: logicalSize,
+        devicePixelRatio: 1.0,
+      ),
+    );
+
+    final PipelineOwner pipelineOwner = PipelineOwner();
+    final BuildOwner buildOwner = BuildOwner(focusManager: FocusManager());
+
+    pipelineOwner.rootNode = renderView;
+    renderView.prepareInitialFrame();
+
+    final RenderObjectToWidgetElement<RenderBox> rootElement =
+        RenderObjectToWidgetAdapter<RenderBox>(
+      container: repaintBoundary,
+      child: Directionality(
+        textDirection: TextDirection.ltr,
+        child: widget,
+      ),
+    ).attachToRenderTree(buildOwner);
+
+    buildOwner.buildScope(rootElement);
+
+    await Future.delayed(delay);
+
+    buildOwner.buildScope(rootElement);
+    buildOwner.finalizeTree();
+
+    pipelineOwner.flushLayout();
+    pipelineOwner.flushCompositingBits();
+    pipelineOwner.flushPaint();
+
+    final ui.Image image = await repaintBoundary.toImage(
+        pixelRatio: imageSize.width / logicalSize.width);
+    final ByteData? byteData =
+        await image.toByteData(format: ui.ImageByteFormat.png);
+
+    return byteData!.buffer.asUint8List();
+  }
 }
 
 class Screenshot<T> extends StatefulWidget {