UnrealEngineUWP/Engine/Source/Editor/MaterialEditor/Private/MaterialEditorDetailCustomization.h

// Copyright 1998-2014 Epic Games, Inc. All Rights Reserved.

#pragma once


DECLARE_DELEGATE_OneParam(FOnCollectParameterGroups, TArray<FString>*);

class FMaterialExpressionParameterDetails : public IDetailCustomization
{
public:

	/** Makes a new instance of this detail layout class for a specific detail view requesting it */
	static TSharedRef<class IDetailCustomization> MakeInstance(FOnCollectParameterGroups InCollectGroupsDelegate);
	
	/** Constructor requires a delegate to populate group names with */
	FMaterialExpressionParameterDetails(FOnCollectParameterGroups InCollectGroupsDelegate);

	/** IDetailCustomization interface */
	virtual void CustomizeDetails( IDetailLayoutBuilder& DetailLayout ) override;

private:
	/** Populates the group name that this parameter details uses */
	void PopulateGroups();

	/** Functions used to make the custom combo button with editable text */
	TSharedRef< ITableRow > MakeDetailsGroupViewWidget( TSharedPtr<FString> Item, const TSharedRef< STableViewBase >& OwnerTable );
	void OnSelectionChanged( TSharedPtr<FString> ProposedSelection, ESelectInfo::Type SelectInfo );
	void OnTextCommitted( const FText& InText, ETextCommit::Type CommitInfo);
	FString OnGetString() const;
	FText OnGetText() const;

private:
	/** The property handle to the groups */
	TSharedPtr<class IPropertyHandle> GroupPropertyHandle;

	/** Custom widgets (combo button with editable text) to access the property with */
	TWeakPtr<SComboButton> GroupComboButton;
	TWeakPtr<SEditableText> GroupEditBox;
	TWeakPtr<SListView<TSharedPtr<FString>>> GroupListView;

	/** Delegate to call to collect a list of groups with */
	FOnCollectParameterGroups CollectGroupsDelegate;

	/** A list of all group names to choose from */
	TArray<TSharedPtr<FString>> GroupsSource;
};

/** 
 * Customizes the details of a CollectionParameter node, 
 * specifically creating a vertical box for ParameterName with only valid entries based on the current collection. 
 */
class FMaterialExpressionCollectionParameterDetails : public IDetailCustomization
{
public:

	/** Makes a new instance of this detail layout class for a specific detail view requesting it */
	static TSharedRef<class IDetailCustomization> MakeInstance();

	/** Constructor requires a delegate to populate group names with */
	FMaterialExpressionCollectionParameterDetails();

	/** IDetailCustomization interface */
	virtual void CustomizeDetails( IDetailLayoutBuilder& DetailLayout ) override;

private:
	/** Populates the group name that this parameter details uses */
	void PopulateParameters();

	/** Functions used to make the custom combo button with editable text */
	TSharedRef< ITableRow > MakeDetailsGroupViewWidget( TSharedPtr<FString> Item, const TSharedRef< STableViewBase >& OwnerTable );
	void OnSelectionChanged( TSharedPtr<FString> ProposedSelection, ESelectInfo::Type SelectInfo );

	FString GetToolTipText() const;
	FString GetParameterNameString() const;
	bool IsParameterNameComboEnabled() const;
	void OnCollectionChanged();

private:

	TSharedPtr<class IPropertyHandle> CollectionPropertyHandle;

	/** The property handle to the parameter name */
	TSharedPtr<class IPropertyHandle> ParameterNamePropertyHandle;

	TWeakPtr<SComboButton> ParameterComboButton;
	TWeakPtr<SListView<TSharedPtr<FString>>> ParameterListView;

	/** A list of all parameter names to choose from */
	TArray<TSharedPtr<FString>> ParametersSource;
};