www.pudn.com > ThemedRichEdit_Redis.zip > RichEditThemed.cpp
//////////////////////////////////////////////////////////////////////////////
// Themed RichEdit Class Helper for Visual C++ //
// Created by Patchou, originally for Messenger Plus! //
// //
// RichEditThemed.cpp - Last Revision: 27/11/2004 //
// Purpose: adds Windows XP theme support to Rich Edit controls //
// //
// This library is free as in NOT under GPL license. You can use it in any //
// program, in the binary form of your choice, and without being asked to //
// add unnecessary files to your redistribution package. Free source //
// should neither be restrained by a 6 page license nor should it force //
// you to share the source of any part of a program you do not wish to //
// share. The meaning of the word freedom is the same for everyone, no //
// license should have the pretension of redefining it. If you want to //
// share some source code, please use a similar copyright notice, your //
// peers will be grateful. //
// //
// Free redistribution and usage of the content of this file is permitted //
// as long as the above statement is kept, unchanged, at its original //
// location. //
// //
//////////////////////////////////////////////////////////////////////////////
#include "stdafx.h"
#include "RichEditThemed.h"
//This STL map is used to keep track of all the instances of the class
std::map CRichEditThemed::m_aInstances;
//The theme-specific functions are imported at runtime for backward compatibility reasons
//A nicer alternative if you are using Visual C++ 7.0 or above is the use of the "delay load" mechanism
HMODULE CRichEditThemed::m_hUxTheme = NULL;
HTHEME (WINAPI *CRichEditThemed::pOpenThemeData)(HWND, LPCWSTR) = NULL;
HRESULT (WINAPI *CRichEditThemed::pCloseThemeData)(HTHEME) = NULL;
HRESULT (WINAPI *CRichEditThemed::pDrawThemeBackground)(HTHEME, HDC, int, int, const RECT*, const RECT *) = NULL;
HRESULT (WINAPI *CRichEditThemed::pGetThemeBackgroundContentRect)(HTHEME, HDC, int, int, const RECT *, RECT *) = NULL;
BOOL (WINAPI *CRichEditThemed::pIsThemeActive)(HTHEME, int, int) = NULL;
HRESULT (WINAPI *CRichEditThemed::pDrawThemeParentBackground)(HWND, HDC, RECT*) = NULL;
BOOL (WINAPI *CRichEditThemed::pIsThemeBackgroundPartiallyTransparent)(HTHEME, int, int) = NULL;
//
// This function is the one and only public function your program must use
// It needs to be called during the creation/initialisation of the parent window
//////////////////////////////////////////////////////////////////////////////
bool CRichEditThemed::Attach(HWND hRichEdit)
{
if(IsWindow(hRichEdit)) //It is your responsibility to ensure that the handle parameter is, indeed, a richedit window
{
//Prevent double subclassing
if(CRichEditThemed::m_aInstances.find(hRichEdit) == CRichEditThemed::m_aInstances.end())
{
//If this function fails, this version of Windows doesn't support themes
if(InitLibrary())
{
//Note: the object will be automatically deleted when the richedit control dies
CRichEditThemed *obj = new CRichEditThemed(hRichEdit);
return true;
}
}
}
return false;
}
//
//////////////////////////////////////////////////////////////////////////////
CRichEditThemed::CRichEditThemed(HWND hRichEdit) : m_hRichEdit(hRichEdit), m_bThemedBorder(false)
{
//Subclass the richedit control, this way, the caller doesn't have to relay the messages by itself
m_aInstances[hRichEdit] = this;
m_pOriginalWndProc = (WNDPROC)SetWindowLong(hRichEdit, GWL_WNDPROC, (LONG)&RichEditStyledProc);
//Check the current state of the richedit control
ZeroMemory(&m_rcClientPos, sizeof(RECT));
VerifyThemedBorderState();
}
//
//////////////////////////////////////////////////////////////////////////////
CRichEditThemed::~CRichEditThemed()
{
//Fail-safe: don't restore the original wndproc pointer if it has been modified since the creation of this object
if((WNDPROC)GetWindowLong(m_hRichEdit, GWL_WNDPROC) == &RichEditStyledProc)
SetWindowLong(m_hRichEdit, GWL_WNDPROC, (LONG)m_pOriginalWndProc);
//Unload the UxTheme library if it is not needed anymore by a control
m_aInstances.erase(m_hRichEdit);
if(m_aInstances.empty())
{
pOpenThemeData = NULL;
pCloseThemeData = NULL;
pDrawThemeBackground = NULL;
pGetThemeBackgroundContentRect = NULL;
pIsThemeActive = NULL;
pDrawThemeParentBackground = NULL;
pIsThemeBackgroundPartiallyTransparent = NULL;
FreeLibrary(m_hUxTheme);
m_hUxTheme = NULL;
}
}
//
//////////////////////////////////////////////////////////////////////////////
bool CRichEditThemed::InitLibrary()
{
//Are we already initialised?
if(pOpenThemeData && pCloseThemeData && pDrawThemeBackground && pGetThemeBackgroundContentRect &&
pIsThemeActive && pDrawThemeParentBackground && pIsThemeBackgroundPartiallyTransparent)
return true;
//Try to get the function pointers of the UxTheme library
if(!m_hUxTheme)
{
m_hUxTheme = LoadLibrary(_T("UxTheme.dll"));
if(!m_hUxTheme)
return false;
}
pOpenThemeData = (HTHEME (WINAPI *)(HWND, LPCWSTR))GetProcAddress(m_hUxTheme, "OpenThemeData");
pCloseThemeData = (HRESULT (WINAPI *)(HTHEME))GetProcAddress(m_hUxTheme, "CloseThemeData");
pDrawThemeBackground = (HRESULT (WINAPI *)(HTHEME, HDC, int, int, const RECT*, const RECT *))GetProcAddress(m_hUxTheme, "DrawThemeBackground");
pGetThemeBackgroundContentRect = (HRESULT (WINAPI *)(HTHEME, HDC, int, int, const RECT *, RECT *))GetProcAddress(m_hUxTheme, "GetThemeBackgroundContentRect");
pIsThemeActive = (BOOL (WINAPI *)())GetProcAddress(m_hUxTheme, "IsThemeActive");
pDrawThemeParentBackground = (HRESULT (WINAPI *)(HWND, HDC, RECT*))GetProcAddress(m_hUxTheme, "DrawThemeParentBackground");
pIsThemeBackgroundPartiallyTransparent = (BOOL (WINAPI *)(HTHEME, int, int))GetProcAddress(m_hUxTheme, "IsThemeBackgroundPartiallyTransparent");
if(pOpenThemeData && pCloseThemeData && pDrawThemeBackground && pGetThemeBackgroundContentRect &&
pIsThemeActive && pDrawThemeParentBackground && pIsThemeBackgroundPartiallyTransparent)
return true;
else
return false;
}
//
//////////////////////////////////////////////////////////////////////////////
LRESULT CALLBACK CRichEditThemed::RichEditStyledProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
//This function is the subclassed winproc of the richedit control
//It is used to monitor the actions of the control, in a nice and transparent manner
std::map::iterator itCurInstance = m_aInstances.find(hwnd);
if(itCurInstance != m_aInstances.end())
{
//A winproc is always static, this one is common to all the richedit controls managed by this class
//We need to get a pointer to the object controlling the richedit which is receiving this message
CRichEditThemed *pObj = itCurInstance->second;
//If you get a compilation error here, it is probably because _WIN32_WINNT is not defined to at least 0x0501
if(uMsg == WM_THEMECHANGED || uMsg == WM_STYLECHANGED)
{
//Someone just changed the style of the richedit control or the user changed its theme
//Make sure the control is being kept up to date by verifying its state
pObj->VerifyThemedBorderState();
}
else if(uMsg == WM_NCPAINT)
{
//Let the control paint its own non-client elements (such as its scrollbars)
LRESULT nOriginalReturn = CallWindowProc(pObj->m_pOriginalWndProc, hwnd, uMsg, wParam, lParam);
//Draw the theme, if necessary
if(pObj->OnNCPaint())
return 0;
else
return nOriginalReturn;
}
else if(uMsg == WM_ENABLE)
{
//Redraw the border depending on the state of the richedit control
RedrawWindow(hwnd, NULL, NULL, RDW_INVALIDATE|RDW_NOCHILDREN|RDW_UPDATENOW|RDW_FRAME);
}
else if(uMsg == WM_NCCALCSIZE)
{
//If wParam is FALSE, we don't need to make any calculation
if(wParam)
{
//Ask the control to first calculate the space it needs
LRESULT nOriginalReturn = CallWindowProc(pObj->m_pOriginalWndProc, hwnd, uMsg, wParam, lParam);
//Alter the size for our own border, if necessary
NCCALCSIZE_PARAMS *csparam = (NCCALCSIZE_PARAMS*)lParam;
if(pObj->OnNCCalcSize(csparam))
return WVR_REDRAW;
else
return nOriginalReturn;
}
}
else if(uMsg == WM_DESTROY)
{
//Send the message now so that we can safely delete the object afterward
LRESULT nToReturn = CallWindowProc(pObj->m_pOriginalWndProc, hwnd, uMsg, wParam, lParam);
delete pObj;
return nToReturn;
}
return CallWindowProc(pObj->m_pOriginalWndProc, hwnd, uMsg, wParam, lParam);
}
else
return 0;
}
//
//////////////////////////////////////////////////////////////////////////////
void CRichEditThemed::VerifyThemedBorderState()
{
bool bCurrentThemedBorder = m_bThemedBorder;
m_bThemedBorder = false;
//First, check if the control is supposed to have a border
if(bCurrentThemedBorder
|| (GetWindowLong(m_hRichEdit, GWL_STYLE) & WS_BORDER || GetWindowLong(m_hRichEdit, GWL_EXSTYLE) & WS_EX_CLIENTEDGE))
{
//Check if a theme is presently active
if(pIsThemeActive())
{
//Remove the border style, we don't want the control to draw its own border
m_bThemedBorder = true;
if(GetWindowLong(m_hRichEdit, GWL_STYLE) & WS_BORDER)
SetWindowLong(m_hRichEdit, GWL_STYLE, GetWindowLong(m_hRichEdit, GWL_STYLE)^WS_BORDER);
if(GetWindowLong(m_hRichEdit, GWL_EXSTYLE) & WS_EX_CLIENTEDGE)
SetWindowLong(m_hRichEdit, GWL_EXSTYLE, GetWindowLong(m_hRichEdit, GWL_EXSTYLE)^WS_EX_CLIENTEDGE);
}
}
//Recalculate the NC area and repaint the window
SetWindowPos(m_hRichEdit, NULL, NULL, NULL, NULL, NULL, SWP_NOMOVE|SWP_NOSIZE|SWP_NOZORDER|SWP_NOACTIVATE|SWP_FRAMECHANGED);
RedrawWindow(m_hRichEdit, NULL, NULL, RDW_INVALIDATE|RDW_NOCHILDREN|RDW_UPDATENOW|RDW_FRAME);
}
//
//////////////////////////////////////////////////////////////////////////////
bool CRichEditThemed::OnNCPaint()
{
try
{
if(m_bThemedBorder)
{
HTHEME hTheme = pOpenThemeData(m_hRichEdit, L"edit");
if(hTheme)
{
HDC hdc = GetWindowDC(m_hRichEdit);
//Clip the DC so that we only draw on the non-client area
RECT rcBorder;
GetWindowRect(m_hRichEdit, &rcBorder);
rcBorder.right -= rcBorder.left; rcBorder.bottom -= rcBorder.top;
rcBorder.left = rcBorder.top = 0;
RECT rcClient; memcpy(&rcClient, &rcBorder, sizeof(RECT));
rcClient.left += m_rcClientPos.left;
rcClient.top += m_rcClientPos.top;
rcClient.right -= m_rcClientPos.right;
rcClient.bottom -= m_rcClientPos.bottom;
ExcludeClipRect(hdc, rcClient.left, rcClient.top, rcClient.right, rcClient.bottom);
//Make sure the background is in a proper state
if(pIsThemeBackgroundPartiallyTransparent(hTheme, EP_EDITTEXT, ETS_NORMAL))
pDrawThemeParentBackground(m_hRichEdit, hdc, &rcBorder);
//Draw the border of the edit box
int nState;
if(!IsWindowEnabled(m_hRichEdit))
nState = ETS_DISABLED;
else if(SendMessage(m_hRichEdit, EM_GETOPTIONS, NULL, NULL) & ECO_READONLY)
nState = ETS_READONLY;
else
nState = ETS_NORMAL;
pDrawThemeBackground(hTheme, hdc, EP_EDITTEXT, nState, &rcBorder, NULL);
pCloseThemeData(hTheme);
ReleaseDC(m_hRichEdit, hdc);
return true;
}
}
}
catch(...)
{
//No exception is supposed to be thrown here but you can never be too safe
//Trace an error here with your favorite TRACE macro
}
return false;
}
//
//////////////////////////////////////////////////////////////////////////////
bool CRichEditThemed::OnNCCalcSize(NCCALCSIZE_PARAMS *csparam)
{
try
{
//Here, we indicate to Windows that the non-client area of the richedit control is not what it thinks it should be
//This gives us the necessary space to draw the special border later on
if(m_bThemedBorder)
{
//Load the theme associated with edit boxes
HTHEME hTheme = pOpenThemeData(m_hRichEdit, L"edit");
if(hTheme)
{
bool bToReturn = false;
//Get the size required by the current theme to be displayed properly
RECT rcClient; ZeroMemory(&rcClient, sizeof(RECT));
HDC hdc = GetDC(GetParent(m_hRichEdit));
if(pGetThemeBackgroundContentRect(hTheme, hdc, EP_EDITTEXT, ETS_NORMAL,
&csparam->rgrc[0], &rcClient) == S_OK)
{
//Add a pixel to every edge so that the client area is not too close to the border drawn by the theme (thus simulating a native edit box)
InflateRect(&rcClient, -1, -1);
m_rcClientPos.left = rcClient.left-csparam->rgrc[0].left;
m_rcClientPos.top = rcClient.top-csparam->rgrc[0].top;
m_rcClientPos.right = csparam->rgrc[0].right-rcClient.right;
m_rcClientPos.bottom = csparam->rgrc[0].bottom-rcClient.bottom;
memcpy(&csparam->rgrc[0], &rcClient, sizeof(RECT));
bToReturn = true;
}
ReleaseDC(GetParent(m_hRichEdit), hdc);
pCloseThemeData(hTheme);
return bToReturn;
}
}
}
catch(...)
{
//No exception is supposed to be thrown here but you can never be too safe
//Trace an error here with your favorite TRACE macro
}
return false;
}