react-native/ReactCommon/fabric/view/ViewShadowNode.cpp

142 lines
3.9 KiB
C++

/**
* Copyright (c) 2015-present, Facebook, Inc.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*/
#include "ViewShadowNode.h"
#include <algorithm>
#include <fabric/debug/DebugStringConvertibleItem.h>
namespace facebook {
namespace react {
#pragma mark - Constructors
ViewShadowNode::ViewShadowNode(
const Tag &tag,
const Tag &rootTag,
const InstanceHandle &instanceHandle,
const SharedViewProps &props,
const SharedShadowNodeSharedList &children
):
ConcreteShadowNode(
tag,
rootTag,
instanceHandle,
props,
children
),
AccessibleShadowNode(
props
),
YogaLayoutableShadowNode(
props,
children
) {};
ViewShadowNode::ViewShadowNode(
const SharedViewShadowNode &shadowNode,
const SharedViewProps &props,
const SharedShadowNodeSharedList &children
):
ConcreteShadowNode(
shadowNode,
props,
children
),
AccessibleShadowNode(
shadowNode,
props
),
YogaLayoutableShadowNode(
shadowNode,
props,
children
) {};
ComponentName ViewShadowNode::getComponentName() const {
return ComponentName("View");
}
void ViewShadowNode::appendChild(const SharedShadowNode &child) {
ensureUnsealed();
ShadowNode::appendChild(child);
auto yogaLayoutableChild = std::dynamic_pointer_cast<const YogaLayoutableShadowNode>(child);
if (yogaLayoutableChild) {
YogaLayoutableShadowNode::appendChild(yogaLayoutableChild);
}
}
#pragma mark - YogaLayoutableShadowNode
SharedLayoutableShadowNodeList ViewShadowNode::getLayoutableChildNodes() const {
SharedLayoutableShadowNodeList sharedLayoutableShadowNodeList = {};
for (auto child : *children_) {
const SharedLayoutableShadowNode layoutableShadowNode = std::dynamic_pointer_cast<const LayoutableShadowNode>(child);
if (!layoutableShadowNode) {
continue;
}
sharedLayoutableShadowNodeList.push_back(layoutableShadowNode);
}
return sharedLayoutableShadowNodeList;
}
SharedLayoutableShadowNode ViewShadowNode::cloneAndReplaceChild(const SharedLayoutableShadowNode &child) {
ensureUnsealed();
auto viewShadowNodeChild = std::dynamic_pointer_cast<const ViewShadowNode>(child);
assert(viewShadowNodeChild);
auto viewShadowNodeChildClone = std::make_shared<ViewShadowNode>(viewShadowNodeChild);
// This is overloading of `SharedLayoutableShadowNode::cloneAndReplaceChild`,
// the method is used to clone some node as a preparation for future mutation
// caused by relayout.
// Because those changes are not requested by UIManager, they add a layer
// of node generation (between the committed stage and new proposed stage).
// That additional layer confuses the Diffing algorithm which uses
// `sourceNode` for referencing the previous (aka committed) stage
// of the tree to produce mutation instructions.
// In other words, if we don't compensate this change here,
// the Diffing algorithm will compare wrong trees
// ("new-but-not-laid-out-yet vs. new" instead of "committed vs. new").
viewShadowNodeChildClone->shallowSourceNode();
ShadowNode::replaceChild(viewShadowNodeChild, viewShadowNodeChildClone);
return std::static_pointer_cast<const LayoutableShadowNode>(viewShadowNodeChildClone);
}
#pragma mark - Equality
bool ViewShadowNode::operator==(const ShadowNode& rhs) const {
if (!ShadowNode::operator==(rhs)) {
return false;
}
auto &&other = static_cast<const ViewShadowNode&>(rhs);
return getLayoutMetrics() == other.getLayoutMetrics();
}
#pragma mark - DebugStringConvertible
SharedDebugStringConvertibleList ViewShadowNode::getDebugProps() const {
SharedDebugStringConvertibleList list = {};
auto basePropsList = ShadowNode::getDebugProps();
std::move(basePropsList.begin(), basePropsList.end(), std::back_inserter(list));
list.push_back(std::make_shared<DebugStringConvertibleItem>("layout", "", YogaLayoutableShadowNode::getDebugProps()));
return list;
}
} // namespace react
} // namespace facebook