Source/WebInspectorUI/UserInterface/Views/View.js - WebKit - Git at Google

 /*
  * Copyright (C) 2015 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
  * THE POSSIBILITY OF SUCH DAMAGE.
  */

 WI.View = class View extends WI.Object
 {
     constructor(element)
     {
         super();

         this._element = element || document.createElement("div");
         this._element.__view = this;
         this._parentView = null;
         this._subviews = [];
         this._dirty = false;
         this._dirtyDescendantsCount = 0;
         this._isAttachedToRoot = false;
         this._layoutReason = null;
         this._didInitialLayout = false;
     }

     // Static

     static fromElement(element)
     {
         if (!element || !(element instanceof HTMLElement))
             return null;

         if (element.__view instanceof WI.View)
             return element.__view;
         return null;
     }

     static rootView()
     {
         if (!WI.View._rootView) {
             // Since the root view is attached by definition, it does not go through the
             // normal view attachment process. Simply mark it as attached.
             WI.View._rootView = new WI.View(document.body);
             WI.View._rootView._isAttachedToRoot = true;
         }

         return WI.View._rootView;
     }

     // Public

     get element() { return this._element; }
     get layoutPending() { return this._dirty; }
     get parentView() { return this._parentView; }
     get subviews() { return this._subviews; }
     get isAttached() { return this._isAttachedToRoot; }

     isDescendantOf(view)
     {
         let parentView = this._parentView;
         while (parentView) {
             if (parentView === view)
                 return true;
             parentView = parentView.parentView;
         }

         return false;
     }

     addSubview(view)
     {
         this.insertSubviewBefore(view, null);
     }

     insertSubviewBefore(view, referenceView)
     {
         console.assert(view instanceof WI.View);
         console.assert(!referenceView || referenceView instanceof WI.View);
         console.assert(view !== WI.View._rootView, "Root view cannot be a subview.");

         console.assert(!view.parentView, view);

         if (this._subviews.includes(view)) {
             console.assert(false, "Cannot add view that is already a subview.", view);
             return;
         }

         const beforeIndex = referenceView ? this._subviews.indexOf(referenceView) : this._subviews.length;
         if (beforeIndex === -1) {
             console.assert(false, "Cannot insert view. Invalid reference view.", referenceView);
             return;
         }

         this._subviews.insertAtIndex(view, beforeIndex);

         console.assert(!view.element.parentNode || this._element.contains(view.element.parentNode), "Subview DOM element must be a descendant of the parent view element.");
         if (!view.element.parentNode)
             this._element.insertBefore(view.element, referenceView ? referenceView.element : null);

         view._didMoveToParent(this);
     }

     removeSubview(view)
     {
         console.assert(view instanceof WI.View);
         console.assert(this._element.contains(view.element), "Subview DOM element must be a child of the parent view element.");

         let index = this._subviews.lastIndexOf(view);
         if (index === -1) {
             console.assert(false, "Cannot remove view which isn't a subview.", view);
             return;
         }

         view._didMoveToParent(null);

         this._subviews.splice(index, 1);
         view.element.remove();
     }

     removeAllSubviews()
     {
         for (let subview of this._subviews)
             subview._didMoveToParent(null);

         this._subviews = [];
         this._element.removeChildren();
     }

     replaceSubview(oldView, newView)
     {
         console.assert(oldView !== newView, "Cannot replace subview with itself.");
         if (oldView === newView)
             return;

         this.insertSubviewBefore(newView, oldView);
         this.removeSubview(oldView);
     }

     updateLayout(layoutReason)
     {
         this._setLayoutReason(layoutReason);
         this._layoutSubtree();
     }

     updateLayoutIfNeeded(layoutReason)
     {
         if (!this._dirty && this._didInitialLayout)
             return;

         this.updateLayout(layoutReason);
     }

     needsLayout(layoutReason)
     {
         this._setLayoutReason(layoutReason);

         if (this._dirty)
             return;

         WI.View._scheduleLayoutForView(this);
     }

     // Protected

     get layoutReason() { return this._layoutReason; }
     get didInitialLayout() { return this._didInitialLayout; }

     attached()
     {
         // Implemented by subclasses.
     }

     detached()
     {
         // Implemented by subclasses.
     }

     initialLayout()
     {
         // Implemented by subclasses.

         // Called once when the view is shown for the first time.
         // Views with complex DOM subtrees should create UI elements in
         // initialLayout rather than at construction time.
     }

     layout()
     {
         // Implemented by subclasses.

         // Not responsible for recursing to child views.
         // Should not be called directly; use updateLayout() instead.
     }

     didLayoutSubtree()
     {
         // Implemented by subclasses.

         // Called after the view and its entire subtree have finished layout.
     }

     sizeDidChange()
     {
         // Implemented by subclasses.

         // Called after initialLayout, and before layout.
     }

     // Private

     _setDirty(dirty)
     {
         if (this._dirty === dirty)
             return;

         this._dirty = dirty;

         for (let parentView = this.parentView; parentView; parentView = parentView.parentView) {
             parentView._dirtyDescendantsCount += this._dirty ? 1 : -1;
             console.assert(parentView._dirtyDescendantsCount >= 0);
         }
     }

     _didMoveToParent(parentView)
     {
         if (this._parentView === parentView)
             return;

         console.assert(this._parentView || !(this._isDirty || this._dirtyDescendantsCount));

         let dirtyDescendantsCount = this._dirtyDescendantsCount;
         if (this._dirty)
             ++dirtyDescendantsCount;

         if (dirtyDescendantsCount) {
             for (let view = this.parentView; view; view = view.parentView) {
                 view._dirtyDescendantsCount -= dirtyDescendantsCount;
                 console.assert(view._dirtyDescendantsCount >= 0);
             }
         }

         this._parentView = parentView;
         let isAttachedToRoot = this.isDescendantOf(WI.View._rootView);

         let views = [this];
         for (let i = 0; i < views.length; ++i) {
             let view = views[i];
             views.pushAll(view.subviews);

             view._dirty = false;
             view._dirtyDescendantsCount = 0;

             if (view._isAttachedToRoot === isAttachedToRoot)
                 continue;

             view._isAttachedToRoot = isAttachedToRoot;
             if (view._isAttachedToRoot)
                 view.attached();
             else
                 view.detached();
         }

         if (isAttachedToRoot)
             WI.View._scheduleLayoutForView(this);
     }

     _layoutSubtree()
     {
         this._setDirty(false);
         let isInitialLayout = !this._didInitialLayout;

         if (isInitialLayout) {
             console.assert(WI.setReentrantCheck(this, "initialLayout"), "ERROR: calling `initialLayout` while already in it", this);
             this.initialLayout();
             this._didInitialLayout = true;
         }

         if (this._layoutReason === WI.View.LayoutReason.Resize || isInitialLayout) {
             console.assert(WI.setReentrantCheck(this, "sizeDidChange"), "ERROR: calling `sizeDidChange` while already in it", this);
             this.sizeDidChange();
             console.assert(WI.clearReentrantCheck(this, "sizeDidChange"), "ERROR: missing return from `sizeDidChange`", this);
         }

         let savedLayoutReason = this._layoutReason;
         if (isInitialLayout) {
             // The initial layout should always be treated as dirty.
             this._setLayoutReason();
         }

         console.assert(WI.setReentrantCheck(this, "layout"), "ERROR: calling `layout` while already in it", this);
         this.layout();
         console.assert(WI.clearReentrantCheck(this, "layout"), "ERROR: missing return from `layout`", this);

         // Ensure that the initial layout override doesn't affects to subviews.
         this._layoutReason = savedLayoutReason;

         if (WI.settings.debugEnableLayoutFlashing.value)
             this._drawLayoutFlashingOutline(isInitialLayout);

         for (let view of this._subviews) {
             view._setLayoutReason(this._layoutReason);
             view._layoutSubtree();
         }

         this._layoutReason = null;

         console.assert(WI.setReentrantCheck(this, "didLayoutSubtree"), "ERROR: calling `didLayoutSubtree` while already in it", this);
         this.didLayoutSubtree();
         console.assert(WI.clearReentrantCheck(this, "didLayoutSubtree"), "ERROR: missing return from `didLayoutSubtree`", this);
     }

     _setLayoutReason(layoutReason)
     {
         this._layoutReason = layoutReason || WI.View.LayoutReason.Dirty;
     }

     _drawLayoutFlashingOutline(isInitialLayout)
     {
         if (this._layoutFlashingTimeout)
             clearTimeout(this._layoutFlashingTimeout);
         else
             this._layoutFlashingPreviousOutline = this._element.style.outline;

         let hue = isInitialLayout ? 20 : 40;
         this._element.style.outline = `1px solid hsla(${hue}, 100%, 51%, 0.8)`;

         this._layoutFlashingTimeout = setTimeout(() => {
             if (this._element)
                 this._element.style.outline = this._layoutFlashingPreviousOutline;

             this._layoutFlashingTimeout = undefined;
             this._layoutFlashingPreviousOutline = null;
         }, 500);
     }

     // Layout controller logic

     static _scheduleLayoutForView(view)
     {
         if (!view._isAttachedToRoot)
             return;

         view._setDirty(true);

         if (WI.View._scheduledLayoutUpdateIdentifier)
             return;

         WI.View._scheduledLayoutUpdateIdentifier = requestAnimationFrame(WI.View._visitViewTreeForLayout);
     }

     static _visitViewTreeForLayout()
     {
         console.assert(WI.View._rootView, "Cannot layout view tree without a root.");

         WI.View._scheduledLayoutUpdateIdentifier = undefined;

         let views = [WI.View._rootView];
         for (let i = 0; i < views.length; ++i) {
             let view = views[i];
             if (view.layoutPending)
                 view._layoutSubtree();
             else if (view._dirtyDescendantsCount)
                 views.pushAll(view.subviews);
         }
     }
 };

 WI.View.LayoutReason = {
     Dirty: Symbol("layout-reason-dirty"),
     Resize: Symbol("layout-reason-resize")
 };

 WI.View._rootView = null;
 WI.View._scheduledLayoutUpdateIdentifier = undefined;
	/*
	* Copyright (C) 2015 Apple Inc. All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution.
	*
	* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
	* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
	* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
	* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
	* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
	* THE POSSIBILITY OF SUCH DAMAGE.
	*/

	WI.View = class View extends WI.Object
	{
	constructor(element)
	{
	super();

	this._element = element \|\| document.createElement("div");
	this._element.__view = this;
	this._parentView = null;
	this._subviews = [];
	this._dirty = false;
	this._dirtyDescendantsCount = 0;
	this._isAttachedToRoot = false;
	this._layoutReason = null;
	this._didInitialLayout = false;
	}

	// Static

	static fromElement(element)
	{
	if (!element \|\| !(element instanceof HTMLElement))
	return null;

	if (element.__view instanceof WI.View)
	return element.__view;
	return null;
	}

	static rootView()
	{
	if (!WI.View._rootView) {
	// Since the root view is attached by definition, it does not go through the
	// normal view attachment process. Simply mark it as attached.
	WI.View._rootView = new WI.View(document.body);
	WI.View._rootView._isAttachedToRoot = true;
	}

	return WI.View._rootView;
	}

	// Public

	get element() { return this._element; }
	get layoutPending() { return this._dirty; }
	get parentView() { return this._parentView; }
	get subviews() { return this._subviews; }
	get isAttached() { return this._isAttachedToRoot; }

	isDescendantOf(view)
	{
	let parentView = this._parentView;
	while (parentView) {
	if (parentView === view)
	return true;
	parentView = parentView.parentView;
	}

	return false;
	}

	addSubview(view)
	{
	this.insertSubviewBefore(view, null);
	}

	insertSubviewBefore(view, referenceView)
	{
	console.assert(view instanceof WI.View);
	console.assert(!referenceView \|\| referenceView instanceof WI.View);
	console.assert(view !== WI.View._rootView, "Root view cannot be a subview.");

	console.assert(!view.parentView, view);

	if (this._subviews.includes(view)) {
	console.assert(false, "Cannot add view that is already a subview.", view);
	return;
	}

	const beforeIndex = referenceView ? this._subviews.indexOf(referenceView) : this._subviews.length;
	if (beforeIndex === -1) {
	console.assert(false, "Cannot insert view. Invalid reference view.", referenceView);
	return;
	}

	this._subviews.insertAtIndex(view, beforeIndex);

	console.assert(!view.element.parentNode \|\| this._element.contains(view.element.parentNode), "Subview DOM element must be a descendant of the parent view element.");
	if (!view.element.parentNode)
	this._element.insertBefore(view.element, referenceView ? referenceView.element : null);

	view._didMoveToParent(this);
	}

	removeSubview(view)
	{
	console.assert(view instanceof WI.View);
	console.assert(this._element.contains(view.element), "Subview DOM element must be a child of the parent view element.");

	let index = this._subviews.lastIndexOf(view);
	if (index === -1) {
	console.assert(false, "Cannot remove view which isn't a subview.", view);
	return;
	}

	view._didMoveToParent(null);

	this._subviews.splice(index, 1);
	view.element.remove();
	}

	removeAllSubviews()
	{
	for (let subview of this._subviews)
	subview._didMoveToParent(null);

	this._subviews = [];
	this._element.removeChildren();
	}

	replaceSubview(oldView, newView)
	{
	console.assert(oldView !== newView, "Cannot replace subview with itself.");
	if (oldView === newView)
	return;

	this.insertSubviewBefore(newView, oldView);
	this.removeSubview(oldView);
	}

	updateLayout(layoutReason)
	{
	this._setLayoutReason(layoutReason);
	this._layoutSubtree();
	}

	updateLayoutIfNeeded(layoutReason)
	{
	if (!this._dirty && this._didInitialLayout)
	return;

	this.updateLayout(layoutReason);
	}

	needsLayout(layoutReason)
	{
	this._setLayoutReason(layoutReason);

	if (this._dirty)
	return;

	WI.View._scheduleLayoutForView(this);
	}

	// Protected

	get layoutReason() { return this._layoutReason; }
	get didInitialLayout() { return this._didInitialLayout; }

	attached()
	{
	// Implemented by subclasses.
	}

	detached()
	{
	// Implemented by subclasses.
	}

	initialLayout()
	{
	// Implemented by subclasses.

	// Called once when the view is shown for the first time.
	// Views with complex DOM subtrees should create UI elements in
	// initialLayout rather than at construction time.
	}

	layout()
	{
	// Implemented by subclasses.

	// Not responsible for recursing to child views.
	// Should not be called directly; use updateLayout() instead.
	}

	didLayoutSubtree()
	{
	// Implemented by subclasses.

	// Called after the view and its entire subtree have finished layout.
	}

	sizeDidChange()
	{
	// Implemented by subclasses.

	// Called after initialLayout, and before layout.
	}

	// Private

	_setDirty(dirty)
	{
	if (this._dirty === dirty)
	return;

	this._dirty = dirty;

	for (let parentView = this.parentView; parentView; parentView = parentView.parentView) {
	parentView._dirtyDescendantsCount += this._dirty ? 1 : -1;
	console.assert(parentView._dirtyDescendantsCount >= 0);
	}
	}

	_didMoveToParent(parentView)
	{
	if (this._parentView === parentView)
	return;

	console.assert(this._parentView \|\| !(this._isDirty \|\| this._dirtyDescendantsCount));

	let dirtyDescendantsCount = this._dirtyDescendantsCount;
	if (this._dirty)
	++dirtyDescendantsCount;

	if (dirtyDescendantsCount) {
	for (let view = this.parentView; view; view = view.parentView) {
	view._dirtyDescendantsCount -= dirtyDescendantsCount;
	console.assert(view._dirtyDescendantsCount >= 0);
	}
	}

	this._parentView = parentView;
	let isAttachedToRoot = this.isDescendantOf(WI.View._rootView);

	let views = [this];
	for (let i = 0; i < views.length; ++i) {
	let view = views[i];
	views.pushAll(view.subviews);

	view._dirty = false;
	view._dirtyDescendantsCount = 0;

	if (view._isAttachedToRoot === isAttachedToRoot)
	continue;

	view._isAttachedToRoot = isAttachedToRoot;
	if (view._isAttachedToRoot)
	view.attached();
	else
	view.detached();
	}

	if (isAttachedToRoot)
	WI.View._scheduleLayoutForView(this);
	}

	_layoutSubtree()
	{
	this._setDirty(false);
	let isInitialLayout = !this._didInitialLayout;

	if (isInitialLayout) {
	console.assert(WI.setReentrantCheck(this, "initialLayout"), "ERROR: calling `initialLayout` while already in it", this);
	this.initialLayout();
	this._didInitialLayout = true;
	}

	if (this._layoutReason === WI.View.LayoutReason.Resize \|\| isInitialLayout) {
	console.assert(WI.setReentrantCheck(this, "sizeDidChange"), "ERROR: calling `sizeDidChange` while already in it", this);
	this.sizeDidChange();
	console.assert(WI.clearReentrantCheck(this, "sizeDidChange"), "ERROR: missing return from `sizeDidChange`", this);
	}

	let savedLayoutReason = this._layoutReason;
	if (isInitialLayout) {
	// The initial layout should always be treated as dirty.
	this._setLayoutReason();
	}

	console.assert(WI.setReentrantCheck(this, "layout"), "ERROR: calling `layout` while already in it", this);
	this.layout();
	console.assert(WI.clearReentrantCheck(this, "layout"), "ERROR: missing return from `layout`", this);

	// Ensure that the initial layout override doesn't affects to subviews.
	this._layoutReason = savedLayoutReason;

	if (WI.settings.debugEnableLayoutFlashing.value)
	this._drawLayoutFlashingOutline(isInitialLayout);

	for (let view of this._subviews) {
	view._setLayoutReason(this._layoutReason);
	view._layoutSubtree();
	}

	this._layoutReason = null;

	console.assert(WI.setReentrantCheck(this, "didLayoutSubtree"), "ERROR: calling `didLayoutSubtree` while already in it", this);
	this.didLayoutSubtree();
	console.assert(WI.clearReentrantCheck(this, "didLayoutSubtree"), "ERROR: missing return from `didLayoutSubtree`", this);
	}

	_setLayoutReason(layoutReason)
	{
	this._layoutReason = layoutReason \|\| WI.View.LayoutReason.Dirty;
	}

	_drawLayoutFlashingOutline(isInitialLayout)
	{
	if (this._layoutFlashingTimeout)
	clearTimeout(this._layoutFlashingTimeout);
	else
	this._layoutFlashingPreviousOutline = this._element.style.outline;

	let hue = isInitialLayout ? 20 : 40;
	this._element.style.outline = `1px solid hsla(${hue}, 100%, 51%, 0.8)`;

	this._layoutFlashingTimeout = setTimeout(() => {
	if (this._element)
	this._element.style.outline = this._layoutFlashingPreviousOutline;

	this._layoutFlashingTimeout = undefined;
	this._layoutFlashingPreviousOutline = null;
	}, 500);
	}

	// Layout controller logic

	static _scheduleLayoutForView(view)
	{
	if (!view._isAttachedToRoot)
	return;

	view._setDirty(true);

	if (WI.View._scheduledLayoutUpdateIdentifier)
	return;

	WI.View._scheduledLayoutUpdateIdentifier = requestAnimationFrame(WI.View._visitViewTreeForLayout);
	}

	static _visitViewTreeForLayout()
	{
	console.assert(WI.View._rootView, "Cannot layout view tree without a root.");

	WI.View._scheduledLayoutUpdateIdentifier = undefined;

	let views = [WI.View._rootView];
	for (let i = 0; i < views.length; ++i) {
	let view = views[i];
	if (view.layoutPending)
	view._layoutSubtree();
	else if (view._dirtyDescendantsCount)
	views.pushAll(view.subviews);
	}
	}
	};

	WI.View.LayoutReason = {
	Dirty: Symbol("layout-reason-dirty"),
	Resize: Symbol("layout-reason-resize")
	};

	WI.View._rootView = null;
	WI.View._scheduledLayoutUpdateIdentifier = undefined;