using System; using System.Collections.Generic; using Unity.UIWidgets.foundation; using Unity.UIWidgets.ui; using UnityEngine; namespace Unity.UIWidgets.widgets { public class FocusNode : ChangeNotifier { internal FocusScopeNode _parent; internal FocusManager _manager; internal bool _hasKeyboardToken = false; public bool hasFocus { get { FocusNode node = null; if (this._manager != null) { node = this._manager._currentFocus; } return node == this; } } public bool consumeKeyboardToken() { if (!this._hasKeyboardToken) { return false; } this._hasKeyboardToken = false; return true; } public void unfocus() { if (this._parent != null) { this._parent._resignFocus(this); } D.assert(this._parent == null); D.assert(this._manager == null); } public override void dispose() { if (this._manager != null) { this._manager._willDisposeFocusNode(this); } if (this._parent != null) { this._parent._resignFocus(this); } D.assert(this._parent == null); D.assert(this._manager == null); base.dispose(); } internal void _notify() { this.notifyListeners(); } public override string ToString() { return $"{Diagnostics.describeIdentity(this)} hasFocus: {this.hasFocus}"; } } public class FocusScopeNode : DiagnosticableTree { internal FocusManager _manager; internal FocusScopeNode _parent; internal FocusScopeNode _nextSibling; internal FocusScopeNode _previousSibling; internal FocusScopeNode _firstChild; internal FocusScopeNode _lastChild; internal FocusNode _focus; public bool isFirstFocus { get { return this._parent == null || this._parent._firstChild == this; } } internal void _prepend(FocusScopeNode child) { D.assert(child != this); D.assert(child != this._firstChild); D.assert(child != this._lastChild); D.assert(child._parent == null); D.assert(child._manager == null); D.assert(child._nextSibling == null); D.assert(child._previousSibling == null); D.assert(() => { var node = this; while (node._parent != null) { node = node._parent; } D.assert(node != child); return true; }); child._parent = this; child._nextSibling = this._firstChild; if (this._firstChild != null) { this._firstChild._previousSibling = child; } this._firstChild = child; this._lastChild = this._lastChild ?? child; child._updateManager(this._manager); } void _updateManager(FocusManager manager) { Action update = null; update = (child) => { if (child._manager == manager) { return; } child._manager = manager; // We don't proactively null out the manager for FocusNodes because the // manager holds the currently active focus node until the end of the // microtask, even if that node is detached from the focus tree. if (manager != null && child._focus != null) { child._focus._manager = manager; } child._visitChildren(update); }; update(this); } void _visitChildren(Action vistor) { FocusScopeNode child = this._firstChild; while (child != null) { vistor.Invoke(child); child = child._nextSibling; } } bool _debugUltimatePreviousSiblingOf(FocusScopeNode child, FocusScopeNode equals) { while (child._previousSibling != null) { D.assert(child._previousSibling != child); child = child._previousSibling; } return child == equals; } bool _debugUltimateNextSiblingOf(FocusScopeNode child, FocusScopeNode equals) { while (child._nextSibling != null) { D.assert(child._nextSibling != child); child = child._nextSibling; } return child == equals; } internal void _remove(FocusScopeNode child) { D.assert(child._parent == this); D.assert(child._manager == this._manager); D.assert(this._debugUltimatePreviousSiblingOf(child, equals: this._firstChild)); D.assert(this._debugUltimateNextSiblingOf(child, equals: this._lastChild)); if (child._previousSibling == null) { D.assert(this._firstChild == child); this._firstChild = child._nextSibling; } else { child._previousSibling._nextSibling = child._nextSibling; } if (child._nextSibling == null) { D.assert(this._lastChild == child); this._lastChild = child._previousSibling; } else { child._nextSibling._previousSibling = child._previousSibling; } child._previousSibling = null; child._nextSibling = null; child._parent = null; child._updateManager(null); } internal void _didChangeFocusChain() { if (this.isFirstFocus && this._manager != null) { this._manager._markNeedsUpdate(); } } public void requestFocus(FocusNode node) { D.assert(node != null); if (this._focus == node) { return; } if (this._focus != null) { this._focus.unfocus(); } node._hasKeyboardToken = true; this._setFocus(node); } public void autofocus(FocusNode node) { D.assert(node != null); if (this._focus == null) { node._hasKeyboardToken = true; this._setFocus(node); } } public void reparentIfNeeded(FocusNode node) { D.assert(node != null); if (node._parent == null || node._parent == this) { return; } node.unfocus(); D.assert(node._parent == null); if (this._focus == null) { this._setFocus(node); } } internal void _setFocus(FocusNode node) { D.assert(node != null); D.assert(node._parent == null); D.assert(this._focus == null); this._focus = node; this._focus._parent = this; this._focus._manager = this._manager; this._focus._hasKeyboardToken = true; this._didChangeFocusChain(); } internal void _resignFocus(FocusNode node) { D.assert(node != null); if (this._focus != node) { return; } this._focus._parent = null; this._focus._manager = null; this._focus = null; this._didChangeFocusChain(); } public void setFirstFocus(FocusScopeNode child) { D.assert(child != null); D.assert(child._parent == null || child._parent == this); if (this._firstChild == child) { return; } child.detach(); this._prepend(child); D.assert(child._parent == this); this._didChangeFocusChain(); } public void reparentScopeIfNeeded(FocusScopeNode child) { D.assert(child != null); if (child._parent == null || child._parent == this) { return; } if (child.isFirstFocus) { this.setFirstFocus(child); } else { child.detach(); } } public void detach() { this._didChangeFocusChain(); if (this._parent != null) { this._parent._remove(this); } D.assert(this._parent == null); } public override void debugFillProperties(DiagnosticPropertiesBuilder properties) { base.debugFillProperties(properties); if (this._focus != null) { properties.add(new DiagnosticsProperty("focus", this._focus)); } } public override List debugDescribeChildren() { var children = new List(); if (this._firstChild != null) { FocusScopeNode child = this._firstChild; int count = 1; while (true) { children.Add(child.toDiagnosticsNode(name: $"child {count}")); if (child == this._lastChild) { break; } child = child._nextSibling; count += 1; } } return children; } } public class FocusManager { public FocusManager() { this.rootScope._manager = this; D.assert(this.rootScope._firstChild == null); D.assert(this.rootScope._lastChild == null); } public readonly FocusScopeNode rootScope = new FocusScopeNode(); internal readonly FocusScopeNode _noneScope = new FocusScopeNode(); public FocusNode currentFocus { get { return this._currentFocus; } } internal FocusNode _currentFocus; internal void _willDisposeFocusNode(FocusNode node) { D.assert(node != null); if (this._currentFocus == node) { this._currentFocus = null; } } bool _haveScheduledUpdate = false; internal void _markNeedsUpdate() { if (this._haveScheduledUpdate) { return; } this._haveScheduledUpdate = true; Window.instance.scheduleMicrotask(this._update); } internal FocusNode _findNextFocus() { FocusScopeNode scope = this.rootScope; while (scope._firstChild != null) { scope = scope._firstChild; } return scope._focus; } internal void _update() { this._haveScheduledUpdate = false; var nextFocus = this._findNextFocus(); if (this._currentFocus == nextFocus) { return; } var previousFocus = this._currentFocus; this._currentFocus = nextFocus; if (previousFocus != null) { previousFocus._notify(); } if (this._currentFocus != null) { this._currentFocus._notify(); } } public void focusNone(bool focus) { if (focus) { if (this._noneScope._parent != null && this._noneScope.isFirstFocus) { return; } this.rootScope.setFirstFocus(this._noneScope); } else { if (this._noneScope._parent == null) { return; } this._noneScope.detach(); } } public override string ToString() { var status = this._haveScheduledUpdate ? " UPDATE SCHEDULED" : ""; var indent = " "; return string.Format("{1}{2}\n{0}currentFocus: {3}\n{4}", indent, Diagnostics.describeIdentity(this), status, this._currentFocus, this.rootScope.toStringDeep(prefixLineOne: indent, prefixOtherLines: indent)); } } }