mirror of
https://github.com/zhigang1992/react-native.git
synced 2026-04-24 04:16:00 +08:00
b9850844a5
Summary: Setting the right expectations: setting layout constraints might fail. Nothing really changed. Implementing a reliable `constraintLayout` which locks instead of returning immediately requires some additional work and new/additional API. Reviewed By: mdvacca Differential Revision: D10159457 fbshipit-source-id: bb23c7de105629ef086ae0b04667ff32c6ffb81d
101 lines
2.8 KiB
C++
101 lines
2.8 KiB
C++
// Copyright (c) Facebook, Inc. and its affiliates.
|
|
|
|
// 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 {
|
|
|
|
/*
|
|
* Represents the shadow tree and its lifecycle.
|
|
*/
|
|
class ShadowTree final {
|
|
|
|
public:
|
|
|
|
/*
|
|
* Creates a new shadow tree instance with given `rootTag`.
|
|
*/
|
|
ShadowTree(Tag rootTag);
|
|
|
|
~ShadowTree();
|
|
|
|
/*
|
|
* 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.
|
|
* Returns `true` if the operation finished successfully.
|
|
* Can be called from any thread.
|
|
*/
|
|
bool constraintLayout(const LayoutConstraints &layoutConstraints, const LayoutContext &layoutContext) const;
|
|
|
|
#pragma mark - Application
|
|
|
|
/*
|
|
* Create a new shadow tree with given `rootChildNodes` and commit.
|
|
* Can be called from any thread.
|
|
* Returns `true` if the operation finished successfully.
|
|
*/
|
|
bool complete(const SharedShadowNodeUnsharedList &rootChildNodes) const;
|
|
|
|
#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 const *delegate);
|
|
ShadowTreeDelegate const *getDelegate() const;
|
|
|
|
private:
|
|
|
|
UnsharedRootShadowNode cloneRootShadowNode(const LayoutConstraints &layoutConstraints, const LayoutContext &layoutContext) const;
|
|
bool complete(UnsharedRootShadowNode newRootShadowNode) const;
|
|
bool commit(
|
|
const SharedRootShadowNode &oldRootShadowNode,
|
|
const SharedRootShadowNode &newRootShadowNode,
|
|
const ShadowViewMutationList &mutations
|
|
) const;
|
|
void toggleEventEmitters(const ShadowViewMutationList &mutations) const;
|
|
void emitLayoutEvents(const ShadowViewMutationList &mutations) const;
|
|
|
|
/*
|
|
* Return `rootShadowNodeMutex_` protected by `commitMutex_`.
|
|
*/
|
|
SharedRootShadowNode getRootShadowNode() const;
|
|
|
|
const Tag rootTag_;
|
|
mutable SharedRootShadowNode rootShadowNode_; // Protected by `commitMutex_`.
|
|
ShadowTreeDelegate const *delegate_;
|
|
mutable std::mutex commitMutex_;
|
|
};
|
|
|
|
} // namespace react
|
|
} // namespace facebook
|