// Unity C# reference source

// Copyright (c) Unity Technologies. For terms of use, see

// https://unity3d.com/legal/licenses/Unity_Reference_Only_License

using System;

using System.Collections.Generic;

namespace UnityEngine.UIElements

{

public class TemplateContainer : BindableElement

{

public new class UxmlFactory : UxmlFactory<TemplateContainer, UxmlTraits> {}

public new class UxmlTraits : BindableElement.UxmlTraits

{

UxmlStringAttributeDescription m_Template = new UxmlStringAttributeDescription { name = "template", use = UxmlAttributeDescription.Use.Required };

public override IEnumerable<UxmlChildElementDescription> uxmlChildElementsDescription

{

get { yield break; }

}

public override void Init(VisualElement ve, IUxmlAttributes bag, CreationContext cc)

{

base.Init(ve, bag, cc);

TemplateContainer templateContainer = ((TemplateContainer)ve);

templateContainer.templateId = m_Template.GetValueFromBag(bag, cc);

VisualTreeAsset vea = cc.visualTreeAsset.ResolveTemplate(templateContainer.templateId);

if (vea == null)

templateContainer.Add(new Label(string.Format("Unknown Element: '{0}'", templateContainer.templateId)));

else

{

var bagOverrides = (bag as TemplateAsset)?.attributeOverrides;

var contextOverrides = cc.attributeOverrides;

List<TemplateAsset.AttributeOverride> attributeOverrides = null;

if (bagOverrides != null || contextOverrides != null)

{

// We want to add contextOverrides first here, then bagOverrides, as we

// want parent instances to always override child instances.

attributeOverrides = new List<TemplateAsset.AttributeOverride>();

if (contextOverrides != null)

attributeOverrides.AddRange(contextOverrides);

if (bagOverrides != null)

attributeOverrides.AddRange(bagOverrides);

}

vea.CloneTree(templateContainer, cc.slotInsertionPoints, attributeOverrides);

}

if (vea == null)

Debug.LogErrorFormat("Could not resolve template with name '{0}'", templateContainer.templateId);

}

}

public string templateId { get; private set; }

private VisualElement m_ContentContainer;

public TemplateContainer() : this(null) {}

public TemplateContainer(string templateId)

{

this.templateId = templateId;

m_ContentContainer = this;

}

public override VisualElement contentContainer

{

get { return m_ContentContainer; }

}

internal void SetContentContainer(VisualElement content)

{

m_ContentContainer = content;

}

}

}