wxWidgets/include/wx/clntdata.h

/////////////////////////////////////////////////////////////////////////////
// Name:        wx/clntdata.h
// Purpose:     A mixin class for holding a wxClientData or void pointer
// Author:      Robin Dunn
// Modified by:
// Created:     9-Oct-2001
// RCS-ID:      $Id$
// Copyright:   (c) wxWidgets team
// Licence:     wxWindows licence
/////////////////////////////////////////////////////////////////////////////

#ifndef _WX_CLNTDATAH__
#define _WX_CLNTDATAH__

#include "wx/defs.h"
#include "wx/string.h"
#include "wx/hashmap.h"

typedef int (*wxShadowObjectMethod)(void*, void*);
WX_DECLARE_STRING_HASH_MAP_WITH_DECL(
    wxShadowObjectMethod,
    wxShadowObjectMethods,
    class WXDLLIMPEXP_BASE
);
WX_DECLARE_STRING_HASH_MAP_WITH_DECL(
    void *,
    wxShadowObjectFields,
    class WXDLLIMPEXP_BASE
);

class WXDLLIMPEXP_BASE wxShadowObject
{
public:
    wxShadowObject() { }

    void AddMethod( const wxString &name, wxShadowObjectMethod method )
    {
        wxShadowObjectMethods::iterator it = m_methods.find( name );
        if (it == m_methods.end())
            m_methods[ name ] = method;
        else
            it->second = method;
    }

    bool InvokeMethod( const wxString &name, void* window, void* param, int* returnValue )
    {
        wxShadowObjectMethods::iterator it = m_methods.find( name );
        if (it == m_methods.end())
            return false;
        wxShadowObjectMethod method = it->second;
        int ret = (*method)(window, param);
        if (returnValue)
            *returnValue = ret;
        return true;
    }

    void AddField( const wxString &name, void* initialValue = NULL )
    {
        wxShadowObjectFields::iterator it = m_fields.find( name );
        if (it == m_fields.end())
            m_fields[ name ] = initialValue;
        else
            it->second = initialValue;
    }

    void SetField( const wxString &name, void* value )
    {
        wxShadowObjectFields::iterator it = m_fields.find( name );
        if (it == m_fields.end())
            return;
        it->second = value;
    }

    void* GetField( const wxString &name, void *defaultValue = NULL )
    {
        wxShadowObjectFields::iterator it = m_fields.find( name );
        if (it == m_fields.end())
            return defaultValue;
        return it->second;
    }

private:
    wxShadowObjectMethods   m_methods;
    wxShadowObjectFields    m_fields;
};


// ----------------------------------------------------------------------------

// what kind of client data do we have?
enum wxClientDataType
{
    wxClientData_None,    // we don't know yet because we don't have it at all
    wxClientData_Object,  // our client data is typed and we own it
    wxClientData_Void     // client data is untyped and we don't own it
};

class WXDLLIMPEXP_BASE wxClientData
{
public:
    wxClientData() { }
    virtual ~wxClientData() { }
};

class WXDLLIMPEXP_BASE wxStringClientData : public wxClientData
{
public:
    wxStringClientData() : m_data() { }
    wxStringClientData( const wxString &data ) : m_data(data) { }
    void SetData( const wxString &data ) { m_data = data; }
    const wxString& GetData() const { return m_data; }

private:
    wxString  m_data;
};

// This class is a mixin that provides storage and management of "client
// data."  The client data stored can either be a pointer to a wxClientData
// object in which case it is managed by the container (i.e. it will delete
// the data when it's destroyed) or an untyped pointer which won't be deleted
// by the container - but not both of them
//
// NOTE:  This functionality is currently duplicated in wxEvtHandler in order
//        to avoid having more than one vtable in that class hierarchy.

class WXDLLIMPEXP_BASE wxClientDataContainer
{
public:
    wxClientDataContainer();
    virtual ~wxClientDataContainer();

    void SetClientObject( wxClientData *data ) { DoSetClientObject(data); }
    wxClientData *GetClientObject() const { return DoGetClientObject(); }

    void SetClientData( void *data ) { DoSetClientData(data); }
    void *GetClientData() const { return DoGetClientData(); }

protected:
    // The user data: either an object which will be deleted by the container
    // when it's deleted or some raw pointer which we do nothing with. Only
    // one type of data can be used with the given window, i.e. you cannot set
    // the void data and then associate the container with wxClientData or vice
    // versa.
    union
    {
        wxClientData *m_clientObject;
        void         *m_clientData;
    };

    // client data accessors
    virtual void DoSetClientObject( wxClientData *data );
    virtual wxClientData *DoGetClientObject() const;

    virtual void DoSetClientData( void *data );
    virtual void *DoGetClientData() const;

    // what kind of data do we have?
    wxClientDataType m_clientDataType;

};

#include "wx/vector.h"

struct WXDLLIMPEXP_BASE wxClientDataDictionaryPair
{
    wxClientDataDictionaryPair( size_t idx ) : index( idx ), data( 0 ) { }

    size_t index;
    wxClientData* data;
};

// this class is used internally to maintain the association between items
// of (some subclasses of) wxControlWithItems and their client data
// NOTE: this class does not keep track of whether it contains
// wxClientData or void*. The client must ensure that
// it does not contain a mix of the two, and that
// DestroyData is called if it contains wxClientData
class WXDLLIMPEXP_BASE wxClientDataDictionary
{
public:
    wxClientDataDictionary() {}

    // deletes all the data
    void DestroyData()
    {
        for( size_t i = 0, end = m_vec.size(); i != end; ++i )
            delete m_vec[i].data;
        m_vec.clear();
    }

    // if data for the given index is not present, add it,
    // if it is present, delete the old data and replace it with
    // the new one
    void Set( size_t index, wxClientData* data, bool doDelete )
    {
        size_t ptr = Find( index );

        if( !data )
        {
            if( ptr == m_vec.size() ) return;
            if( doDelete )
                delete m_vec[ptr].data;
            m_vec.erase( ptr );
        }
        else
        {
            if( ptr == m_vec.size() )
            {
                m_vec.push_back( wxClientDataDictionaryPair( index ) );
                ptr = m_vec.size() - 1;
            }

            if( doDelete )
                delete m_vec[ptr].data;
            m_vec[ptr].data = data;
        }
    }

    // get the data associated with the given index,
    // return 0 if not found
    wxClientData* Get( size_t index ) const
    {
        size_t it = Find( index );
        if( it == m_vec.size() ) return 0;
        return (wxClientData*)m_vec[it].data; // const cast
    }

    // delete the data associated with the given index
    // it also decreases by one the indices of all the elements
    // with an index greater than the given index
    void Delete( size_t index, bool doDelete )
    {
        size_t todel = m_vec.size();

        for( size_t i = 0, end = m_vec.size(); i != end; ++i )
        {
            if( m_vec[i].index == index )
                todel = i;
            else if( m_vec[i].index > index )
                --(m_vec[i].index);
        }

        if( todel != m_vec.size() )
        {
            if( doDelete )
                delete m_vec[todel].data;
            m_vec.erase( todel );
        }
    }
private:
    // returns MyVec.size() if not found
    size_t Find( size_t index ) const
    {
        for( size_t i = 0, end = m_vec.size(); i != end; ++i )
        {
            if( m_vec[i].index == index )
                return i;
        }

        return m_vec.size();
    }

    wxVector<wxClientDataDictionaryPair> m_vec;
};

#endif // _WX_CLNTDATAH__