Valentin Shergin 0792fba63f Fabric: Using ShadowView instead of ShadowNode in Mutations
Summary:
@public
This is quite a big diff but the actual meaningful change is simple: now we use ShadowView class instead of ShadowNode in mutation instructions.
Note:
 * In some places (especially during diffing) we have to operate with ShadowNodeViewPair objects (which represents a pair of ShadowNode and ShadowView). The reason for that is that we cannot construct child ShadowViews from parent ShadowViews because they don't have any information about children.
 * `ShadowTree::emitLayoutEvents` is now much simpler because ShadowView better represents the specifics of this kind of object.
 * The code in RCTMountingManager also became simpler.

This change will allow us to implement more cool tricks soon.

Reviewed By: mdvacca

Differential Revision: D9403564

fbshipit-source-id: dbc7c61af250144d6c7335a01dc30df0005559a2
2018-09-03 23:04:20 -07:00

97 lines
2.6 KiB
C++

// Copyright (c) 2004-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.
#pragma once
#include <memory>
#include <mutex>
#include <fabric/components/root/RootShadowNode.h>
#include <fabric/core/LayoutConstraints.h>
#include <fabric/core/ReactPrimitives.h>
#include <fabric/core/ShadowNode.h>
#include <fabric/uimanager/ShadowTreeDelegate.h>
#include <fabric/uimanager/ShadowViewMutation.h>
namespace facebook {
namespace react {
class ShadowTree;
using SharedShadowTree = std::shared_ptr<ShadowTree>;
/*
* Represents the shadow tree and its lifecycle.
*/
class ShadowTree final:
public std::enable_shared_from_this<ShadowTree> {
public:
/*
* Creates a new shadow tree instance with given `rootTag`.
*/
ShadowTree(Tag rootTag);
/*
* Returns the rootTag associated with the shadow tree (the tag of the
* root shadow node).
*/
Tag getRootTag() const;
#pragma mark - Layout
/*
* Measures the shadow tree with given `layoutConstraints` and `layoutContext`.
* Can be called from any thread, side-effect-less.
*/
Size measure(const LayoutConstraints &layoutConstraints, const LayoutContext &layoutContext) const;
/*
* Applies given `layoutConstraints` and `layoutContext` and commit
* the new shadow tree.
* Can be called from any thread.
*/
void constraintLayout(const LayoutConstraints &layoutConstraints, const LayoutContext &layoutContext);
#pragma mark - Application
/*
* Create a new shadow tree with given `rootChildNodes` and commit.
* Can be called from any thread.
*/
void complete(const SharedShadowNodeUnsharedList &rootChildNodes);
#pragma mark - Delegate
/*
* Sets and gets the delegate.
* The delegate is stored as a raw pointer, so the owner must null
* the pointer before being destroyed.
*/
void setDelegate(ShadowTreeDelegate *delegate);
ShadowTreeDelegate *getDelegate() const;
private:
UnsharedRootShadowNode cloneRootShadowNode(const LayoutConstraints &layoutConstraints, const LayoutContext &layoutContext) const;
void complete(UnsharedRootShadowNode newRootShadowNode);
bool commit(
const SharedRootShadowNode &oldRootShadowNode,
const SharedRootShadowNode &newRootShadowNode,
const ShadowViewMutationList &mutations
);
void toggleEventEmitters(const ShadowViewMutationList &mutations);
void emitLayoutEvents(const ShadowViewMutationList &mutations);
const Tag rootTag_;
SharedRootShadowNode rootShadowNode_;
ShadowTreeDelegate *delegate_;
mutable std::mutex commitMutex_;
};
} // namespace react
} // namespace facebook