ListTiles & Constraints #1

Author: SaadArdati

lib/src/api/mixins.dart

@@ -579,11 +579,11 @@ mixin GeometryMixin on BaseNode {
   /// If an image is in the fills, allow shrink-wrapping up to to a fixed
   /// minimum.
   @override
-  SizeC minimumInternalSize({
+  BoxConstraintsModel internalConstraints({
     required SizeFit horizontalFit,
     required SizeFit verticalFit,
   }) {
-    SizeC resultSize = super.minimumInternalSize(
+    BoxConstraintsModel resultSize = super.internalConstraints(
       horizontalFit: horizontalFit,
       verticalFit: verticalFit,
     );
@@ -620,7 +620,12 @@ mixin GeometryMixin on BaseNode {
           }
         }
 
-        resultSize = resultSize | size;
+        resultSize = resultSize.enforce(
+          BoxConstraintsModel(
+            minWidth: size.width,
+            minHeight: size.height,
+          ),
+        );
       }
     }
     return resultSize;

lib/src/api/models/box_constraints.dart

@@ -35,6 +35,20 @@ class BoxConstraintsModel with EquatableMixin, SerializableMixin {
     this.maxHeight,
   });
 
+  /// Creates a new instance of this class with the same values as the given
+  /// instance.
+  /// This class uses nullable values for all properties, therefore a standard
+  /// copyWith method is not possible.
+  ///
+  /// For individual properties, use [updateMinWidth], [updateMaxWidth],
+  /// [updateMinHeight], and [updateMaxHeight] instead.
+  BoxConstraintsModel copy() => BoxConstraintsModel(
+        minWidth: minWidth,
+        maxWidth: maxWidth,
+        minHeight: minHeight,
+        maxHeight: maxHeight,
+      );
+
   /// Duplicates instance of this class with given [minWidth] value override.
   BoxConstraintsModel updateMinWidth(double? value) => BoxConstraintsModel(
         minWidth: value,
@@ -177,6 +191,66 @@ class BoxConstraintsModel with EquatableMixin, SerializableMixin {
     );
   }
 
+  /// Creates a union [BoxConstraintsModel] from the current
+  /// [BoxConstraintsModel] and the provided [constraints].
+  ///
+  /// The resulting [BoxConstraintsModel] will have the minimum with and height
+  /// that's the biggest of the two, and the maximum width and height that's
+  /// the smallest of the two.
+  BoxConstraintsModel union(BoxConstraintsModel constraints) {
+    return BoxConstraintsModel(
+      minWidth: (minWidth == null)
+          ? constraints.minWidth
+          : (constraints.minWidth == null)
+              ? minWidth
+              : max(minWidth!, constraints.minWidth!),
+      maxWidth: (maxWidth == null)
+          ? constraints.maxWidth
+          : (constraints.maxWidth == null)
+              ? maxWidth
+              : min(maxWidth!, constraints.maxWidth!),
+      minHeight: (minHeight == null)
+          ? constraints.minHeight
+          : (constraints.minHeight == null)
+              ? minHeight
+              : max(minHeight!, constraints.minHeight!),
+      maxHeight: (maxHeight == null)
+          ? constraints.maxHeight
+          : (constraints.maxHeight == null)
+              ? maxHeight
+              : min(maxHeight!, constraints.maxHeight!),
+    );
+  }
+
+  /// Similar to [union], but will only clamp the minimums and maximums
+  /// if the passed [constraints] of the relevant parameter is not null.
+  ///
+  /// So for example, if the passed [constraints] has a null min width,
+  /// instead of returning a [BoxConstraintsModel] with a null min width,
+  /// it just returns its own if available.
+  /// Otherwise, it takes the biggest of the two min widths.
+  ///
+  /// Another example, if the passed [constraints] has a null max width,
+  /// instead of returning a [BoxConstraintsModel] with a null max width,
+  /// it just returns its own if available.
+  /// Otherwise, it takes the smallest of the two max widths.
+  BoxConstraintsModel unionNonNull(BoxConstraintsModel constraints) {
+    return BoxConstraintsModel(
+      minWidth: constraints.minWidth == null
+          ? minWidth
+          : max(minWidth ?? 0, constraints.minWidth!),
+      maxWidth: constraints.maxWidth == null
+          ? maxWidth
+          : min(maxWidth ?? double.infinity, constraints.maxWidth!),
+      minHeight: constraints.minHeight == null
+          ? minHeight
+          : max(minHeight ?? 0, constraints.minHeight!),
+      maxHeight: constraints.maxHeight == null
+          ? maxHeight
+          : min(maxHeight ?? double.infinity, constraints.maxHeight!),
+    );
+  }
+
   /// Whether this constraints is the same as no constraints which is the
   /// default value.
   bool get isDefault =>

lib/src/api/models/size.dart

@@ -71,10 +71,6 @@ class SizeC with SerializableMixin, EquatableMixin {
   /// Returns scaled down size by given [scale].
   SizeC operator /(double scale) => SizeC(width / scale, height / scale);
 
-  /// Max of two sizes operator.
-  operator |(SizeC size) =>
-      SizeC(max(width, size.width), max(height, size.height));
-
   /// Adds given [size] to this size and returns the result.
   SizeC add(SizeC size) => SizeC(width + size.width, height + size.height);
 

lib/src/api/node_processor.dart

@@ -100,6 +100,7 @@ extension BaseNodeUpdateExtension on BaseNode {
     OuterNodeBox? outerBoxLocal,
     OuterNodeBox? outerBoxGlobal,
     NodeBox? middleBoxLocal,
+    BoxConstraintsModel? constraints,
     int? rotationDegrees,
     bool resetRetainedBox = true,
     bool recursivelyCalculateChildrenGlobalBoxes = true,
@@ -114,6 +115,7 @@ extension BaseNodeUpdateExtension on BaseNode {
         outerBoxLocal: outerBoxLocal,
         outerBoxGlobal: outerBoxGlobal,
         basicBoxLocal: middleBoxLocal,
+        constraints: constraints,
         rotationDegrees: rotationDegrees,
         resetRetainedBox: resetRetainedBox,
         recursivelyCalculateChildrenGlobalBoxes:
@@ -163,6 +165,41 @@ class NodeProcessor {
     NodeProcessor.getNode = getNode;
   }
 
+  /// There are normal [constraints] field, but they do not tell the full
+  /// story of provided node's true constraints.
+  ///
+  /// The [constraints] field is what is manually set by the user. However,
+  /// we have additional constraints that are computed for different nodes.
+  /// Material components may provide additional internal
+  /// constraints. Images may provide their original sizes when shrink-wrapping,
+  /// ListTiles provide a minimum size that the leading node must have, etc...
+  ///
+  /// This function will take the [internalConstraints] and union them to the
+  /// [constraints] field to get a reinforced set of constraints.
+  static BoxConstraintsModel resolveConstraints(
+    BaseNode node, {
+    SizeFit? horizontalFit,
+    SizeFit? verticalFit,
+  }) {
+    BoxConstraintsModel resolved = node.internalConstraints(
+      horizontalFit: horizontalFit ?? node.horizontalFit,
+      verticalFit: verticalFit ?? node.verticalFit,
+    );
+
+    if (node.id != kRootNode) {
+      final BaseNode parent = getNode(node.parentID);
+      final BoxConstraintsModel? relegatedConstraints =
+          parent.relegatedConstraintsToChildren(node);
+      if (relegatedConstraints != null) {
+        final parentResolved =
+            relegatedConstraints.unionNonNull(resolveConstraints(parent));
+        resolved = resolved.unionNonNull(parentResolved);
+      }
+    }
+
+    return node.constraints.unionNonNull(resolved);
+  }
+
   /// Update the global rotation for given [node] with [newRotationDegrees].
   static void updateGlobalRotation({
     required BaseNode node,
@@ -219,6 +256,7 @@ class NodeProcessor {
     OuterNodeBox? outerBoxLocal,
     OuterNodeBox? outerBoxGlobal,
     NodeBox? basicBoxLocal,
+    BoxConstraintsModel? constraints,
     int? rotationDegrees,
     bool resetRetainedBox = true,
     bool recursivelyCalculateChildrenGlobalBoxes = true,
@@ -233,13 +271,18 @@ class NodeProcessor {
         outerBoxGlobal != null && globalParentBoundingBoxPos != null;
     final bool localOuterBoxChanged = outerBoxLocal != null;
     final bool localMiddleBoxChanged = basicBoxLocal != null;
+    final bool constraintsChanged = constraints != null;
 
     if (alignmentChanged) node._alignment = alignment;
     if (marginChanged) node._margin = margin;
     if (paddingChanged) node._padding = padding;
     if (localMiddleBoxChanged) node._basicBoxLocal = basicBoxLocal;
     if (localOuterBoxChanged) node._outerBoxLocal = outerBoxLocal;
     if (outerBoxGlobal != null) node._outerBoxGlobal = outerBoxGlobal;
+    if (constraintsChanged) {
+      node._constraints = constraints;
+    }
+    node._resolvedConstraints = resolveConstraints(node);
 
     node.updateNodeRotation(rotationDegrees ?? node.rotationDegrees);
 

lib/src/api/nodes/accordion_node.g.dart

@@ -61,7 +61,7 @@ class AppBarNode extends SceneNode
   Map toJson() => _$AppBarNodeToJson(this);
 
   @override
-  SizeC minimumInternalSize({
+  BoxConstraintsModel internalConstraints({
     required SizeFit horizontalFit,
     required SizeFit verticalFit,
   }) {
@@ -78,7 +78,12 @@ class AppBarNode extends SceneNode
       minHeight = properties.titleStyle.fontSize + 16;
     }
     minHeight = min(56, minHeight);
-    return SizeC(0, minHeight);
+    return super
+        .internalConstraints(
+            horizontalFit: horizontalFit, verticalFit: verticalFit)
+        .unionNonNull(
+          BoxConstraintsModel(minHeight: minHeight),
+        );
   }
 }