wip

src/flutter/dart/lib/models/DropArea.dart

@@ -84,11 +84,13 @@ class DropArea implements ffi.Finalizable {
 
   void _addGroup(Group group) {
     _groups.add(group);
+    group.dropArea = this;
     layoutChanged.emit();
   }
 
   void _removeGroup(Group group) {
     _groups.remove(group);
+
     Bindings.instance.nativeLibrary
         .remove_guest(_hostCpp.cast(), group.guestCpp.cast());
     layoutChanged.emit();
@@ -145,6 +147,10 @@ class DropArea implements ffi.Finalizable {
     return false;
   }
 
+  bool containsGroup(Group group) {
+    return _groups.contains(group);
+  }
+
   List<Group> get groups {
     return _groups;
   }

src/flutter/dart/lib/models/FloatingItem.dart

@@ -34,9 +34,34 @@ class FloatingItem implements ItemWithTitleBar {
     return dropArea.groups.length > 1;
   }
 
+  bool containsGroup(Group group) {
+    return dropArea.containsGroup(group);
+  }
+
+  void addGroup(Group group) {
+    dropArea._addGroup(group);
+  }
+
   @override
   void close() {
     _groupCountChangedConnection.disconnect();
     DockRegistry.instance.removeFloatingItem(this);
   }
+
+  @override
+  bool isFloating() {
+    // A floating window is floating
+    return true;
+  }
+
+  @override
+  void unfloat() {
+    // attach floating window into main window again
+  }
+
+  @override
+  void float() {
+    // a floating window is already floating
+    throw "unreachable";
+  }
 }

src/flutter/dart/lib/models/Group.dart

@@ -160,8 +160,54 @@ class Group extends GeometryItem implements ffi.Finalizable, ItemWithTitleBar {
     }
   }
 
+  /// Returns the floating item this group is in, if any.
+  /// It might be inside the main window, in which case this returns null
+  FloatingItem? floatingItem() {
+    for (var floatingItem in DockRegistry.instance.floatingItems) {
+      if (floatingItem.containsGroup(this)) return floatingItem;
+    }
+
+    return null;
+  }
+
+  /// If false, then it's inside the main window
+  bool isInFloatingWindow() {
+    return floatingItem() != null;
+  }
+
   @override
   void close() {
     dropArea._removeGroup(this);
   }
+
+  /// A group is floating if:
+  /// It's in a floating window without nesting
+  /// i.e: it's the only group
+  /// i.e: it can't be detached into a floating window
+  @override
+  bool isFloating() {
+    final fi = floatingItem();
+    if (fi == null) {
+      return false;
+    } else {
+      return fi.dropArea.groups.length == 1;
+    }
+  }
+
+  @override
+  void unfloat() {
+    // a group is already attached
+    throw "unreachable";
+  }
+
+  @override
+  void float() {
+    // transform the group into a floating window
+    if (isFloating()) return;
+
+    dropArea._removeGroup(this);
+
+    final floatingItem = FloatingItem();
+    floatingItem.addGroup(this);
+  }
 }

src/flutter/dart/lib/models/TitleBar.dart

@@ -15,6 +15,15 @@ part of kddockwidgets;
 abstract class ItemWithTitleBar {
   // called when close button on the titlebar is clicked
   void close();
+
+  // whether the titlebar is attached to a floating window or group
+  bool isFloating();
+
+  // detaches into a floating window
+  void float();
+
+  // docks a floating window into the main drop area
+  void unfloat();
 }
 
 class TitleBar {
@@ -29,7 +38,17 @@ class TitleBar {
     _itemWithTitleBar.close();
   }
 
-  void onFloatClicked() {}
+  void onFloatClicked() {
+    if (isFloating()) {
+      _itemWithTitleBar.unfloat();
+    } else {
+      _itemWithTitleBar.float();
+    }
+  }
 
   void onMouseEvent(PointerEvent ev) {}
+
+  bool isFloating() {
+    return _itemWithTitleBar.isFloating();
+  }
 }

src/flutter/dart/test/models/floatingitem_test.dart

@@ -0,0 +1,42 @@
+/*
+  This file is part of KDDockWidgets.
+
+  SPDX-FileCopyrightText: 2024 Klarälvdalens Datakonsult AB, a KDAB Group company <[email protected]>
+  Author: Sérgio Martins <[email protected]>
+
+  SPDX-License-Identifier: GPL-2.0-only OR GPL-3.0-only
+
+  Contact KDAB at <[email protected]> for commercial licensing options.
+*/
+
+import 'package:flutter_test/flutter_test.dart';
+import 'package:KDDockWidgets/KDDockWidgets.dart';
+import 'package:KDDockWidgets/private/Bindings.dart';
+
+void main() {
+  group('FloatingItem', () {
+    test('isFloating', () {
+      var dropArea = DropArea();
+      final dockName = "dock1";
+      expect(dropArea.containsDockItem(dockName), false);
+      var dock = DockItem(uniqueName: dockName);
+      dropArea.addDockItem(dock, Location.LocationOnTop);
+
+      var group = dropArea.groups.first;
+      // It's docked, so not floating yet
+      expect(group.isFloating(), false);
+      expect(dropArea.groups.length, 1);
+      expect(group.dropArea, dropArea);
+
+      // Undock:
+      group.titlebar.onFloatClicked();
+      expect(group.isFloating(), true);
+      expect(dropArea.groups.length, 0);
+      expect(group.dropArea != dropArea, true);
+
+      // Redock:
+      // group.titlebar.onFloatClicked();
+      // expect(group.isFloating(), false);
+    });
+  });
+}