////////////////////////////////////////////////////////////////////////////////////////////////////
// NoesisGUI - http://www.noesisengine.com
// Copyright (c) 2013 Noesis Technologies S.L. All Rights Reserved.
////////////////////////////////////////////////////////////////////////////////////////////////////


#ifndef __GUI_ITEMSPRESENTER_H__
#define __GUI_ITEMSPRESENTER_H__


#include <NsCore/Noesis.h>
#include <NsGui/CoreApi.h>
#include <NsGui/FrameworkElement.h>


namespace Noesis
{

class Panel;
class ItemContainerGenerator;
class ScrollContentPresenter;

////////////////////////////////////////////////////////////////////////////////////////////////////
/// Used within the template of an ItemControl to specify the place in the control's visual tree
/// where the ItemsPanel defined by the ItemsControl is to be added.
///
/// http://msdn.microsoft.com/en-us/library/system.windows.controls.itemspresenter.aspx
////////////////////////////////////////////////////////////////////////////////////////////////////
class NS_GUI_CORE_API ItemsPresenter: public FrameworkElement
{
public:
    ItemsPresenter();
    ~ItemsPresenter();

protected:
    /// From FrameworkElement
    //@{
    Size MeasureOverride(const Size& availableSize) override;
    void OnTemplatedParentChanged(FrameworkElement* oldParent,
        FrameworkElement* newParent) override;
    //@}

private:
    friend class ItemsControl;
    friend class ItemContainerGenerator;
    friend class ScrollContentPresenter;

    static ItemsPresenter* FromPanel(Panel* panel);
    ItemContainerGenerator* GetGenerator() const;

    void InvalidateItemsHost();
    void RefreshItemsHost();

    void SetScrollPresenter(ScrollContentPresenter* scrollPresenter);
    void UpdateScrollPresenter();
    void OnPresenterDestroyed(DependencyObject* d);

private:
    bool mRefreshItemsHost;
    ScrollContentPresenter* mScrollPresenter;

    NS_DECLARE_REFLECTION(ItemsPresenter, FrameworkElement)
};

}


#endif