opt ui

Signed-off-by: dom <githubaccount56556@proton.me>

lib/common/widgets/main_layout.dart

@@ -0,0 +1,121 @@
+import 'package:flutter/material.dart';
+import 'package:flutter/rendering.dart'
+    show BoxParentData, BoxHitTestResult, ChildLayoutHelper;
+
+enum MainType { sideBar, body, bottomNav }
+
+class MainLayout
+    extends SlottedMultiChildRenderObjectWidget<MainType, RenderBox> {
+  const MainLayout({
+    super.key,
+    required this.sideBar,
+    required this.bottomNav,
+    required this.body,
+  });
+
+  final Widget? sideBar;
+  final Widget? bottomNav;
+  final Widget body;
+
+  @override
+  Iterable<MainType> get slots => MainType.values;
+
+  @override
+  Widget? childForSlot(slot) => switch (slot) {
+    .sideBar => sideBar,
+    .bottomNav => bottomNav,
+    .body => body,
+  };
+
+  @override
+  SlottedContainerRenderObjectMixin<MainType, RenderBox> createRenderObject(
+    BuildContext context,
+  ) {
+    return _RenderMainLayout();
+  }
+}
+
+class _RenderMainLayout extends RenderBox
+    with SlottedContainerRenderObjectMixin<MainType, RenderBox> {
+  Offset _getOffset(RenderBox child) {
+    return (child.parentData as BoxParentData).offset;
+  }
+
+  void _setOffset(RenderBox child, Offset offset) {
+    (child.parentData as BoxParentData).offset = offset;
+  }
+
+  @override
+  void performLayout() {
+    final constraints = this.constraints;
+    size = constraints.biggest;
+
+    final Offset bodyOffset;
+    final BoxConstraints bodyConstraints;
+
+    final sideBar = childForSlot(.sideBar);
+    if (sideBar != null) {
+      final sideBarWidth = ChildLayoutHelper.layoutChild(
+        sideBar,
+        BoxConstraints.tightFor(height: constraints.maxHeight),
+      ).width;
+      _setOffset(sideBar, .zero);
+
+      bodyOffset = Offset(sideBarWidth, 0);
+      bodyConstraints = BoxConstraints.tightFor(
+        width: constraints.maxWidth - sideBarWidth,
+        height: constraints.maxHeight,
+      );
+    } else {
+      final bottomNav = childForSlot(.bottomNav);
+      if (bottomNav != null) {
+        final bottomNavSize = ChildLayoutHelper.layoutChild(
+          bottomNav,
+          constraints.loosen(),
+        );
+        _setOffset(
+          bottomNav,
+          Offset(
+            (constraints.maxWidth - bottomNavSize.width) / 2,
+            constraints.maxHeight - bottomNavSize.height,
+          ),
+        );
+      }
+
+      bodyOffset = .zero;
+      bodyConstraints = BoxConstraints.tightFor(
+        width: constraints.maxWidth,
+        height: constraints.maxHeight,
+      );
+    }
+
+    final body = childForSlot(.body)!..layout(bodyConstraints);
+    _setOffset(body, bodyOffset);
+  }
+
+  @override
+  void paint(PaintingContext context, Offset offset) {
+    for (final child in children) {
+      context.paintChild(child, _getOffset(child) + offset);
+    }
+  }
+
+  @override
+  bool hitTestChildren(BoxHitTestResult result, {required Offset position}) {
+    for (final type in MainType.values.reversed) {
+      final child = childForSlot(type);
+      if (child == null) continue;
+      final bool isHit = result.addWithPaintOffset(
+        offset: _getOffset(child),
+        position: position,
+        hitTest: (BoxHitTestResult result, Offset transformed) {
+          return child.hitTest(result, position: transformed);
+        },
+      );
+      if (isHit) {
+        return true;
+      }
+    }
+    return false;
+  }
+}