am trying to create class to encapsulate toolbar but the background turns black. c++ win32api

Question

i created a simple class to hide the details of creating a toolbar in win32 api but i dont like the toolbars it is producing. (See image for clarification. I dont have reputation points so i have just posted a link)

http://i35.tinypic.com/1zmfeip.jpg

I have no idea now the black background is coming into my application.
Here is the class declaration in file CToolBar.h

#ifndef _CTOOLBAR_H
#define _CTOOLBAR_H

#include<windows.h>
#include<commctrl.h>

class CToolBar
{
public:
       CToolBar();//constructor
       ~CToolBar();//destructor

       void AddButton(int iconID, int command);//add Both a button, its icon and its command ID
       void Show();//display the toolbar
       void Initialise(HINSTANCE hInst, HWND hParent);
protected:
          HINSTANCE m_hInst;
          HWND m_hParent;
          HWND m_hToolBar;
          HIMAGELIST m_hImageList;
          TBBUTTON m_Tbb[4];  //toolbar buttons
          int m_numberButtons;     
};
#endif

here is the implementation in file CToolBar.cpp

//CToolBar.cpp
#include "CToolBar.h"
#include<windows.h>
#include<commctrl.h>

CToolBar::CToolBar()//the constructor
{
    m_hImageList=ImageList_Create(32, 32, ILC_COLOR32, 0, 15);//returns NULL if the fuction fails
   //finish other initialisations
   InitCommonControls();//initialise commctrl.dll whatever.. or else your toolbar wont appear
  }

void CToolBar::Initialise(HINSTANCE hInst, HWND hParent)
{
  m_hInst=hInst;
  m_hParent=hParent; 

  m_hToolBar=CreateWindowEx(
                WS_EX_PALETTEWINDOW ,
                TOOLBARCLASSNAME,
                "",
                WS_CHILD | WS_CLIPCHILDREN | WS_CLIPSIBLINGS |WS_VISIBLE|TBSTYLE_BUTTON | TBSTYLE_TOOLTIPS | CCS_ADJUSTABLE | CCS_TOP ,
                0, 0,
                0, 0,
                m_hParent,
       NULL,
                m_hInst,
                0);
}

CToolBar::~CToolBar()//destructor
{
 ImageList_Destroy(m_hImageList);
}

void CToolBar::AddButton(int iconID, int command)
{
     HICON hIcon = LoadIcon(m_hInst, MAKEINTRESOURCE(iconID));
     ImageList_AddIcon(m_hImageList, hIcon);
     DeleteObject(hIcon); 

if(iconID!= -1)//-1 means the separator. The rest are mere buttons
{     
     m_Tbb[m_numberButtons].iBitmap =m_numberButtons;
     m_Tbb[m_numberButtons].idCommand = command;
     m_Tbb[m_numberButtons].fsState = TBSTATE_ENABLED;
     m_Tbb[m_numberButtons].fsStyle = TBSTYLE_BUTTON; 
     m_Tbb[m_numberButtons].dwData = 0; 
     m_Tbb[m_numberButtons].iString = 0;
}
else//ie if (iconID== -1) ; then display the separator. the command value is ignored
{
     m_Tbb[m_numberButtons].iBitmap =-1;
     m_Tbb[m_numberButtons].idCommand = 0;
     m_Tbb[m_numberButtons].fsState = TBSTATE_ENABLED;
     m_Tbb[m_numberButtons].fsStyle = TBSTYLE_SEP; 
     m_Tbb[m_numberButtons].dwData = 0; 
     m_Tbb[m_numberButtons].iString = 0;

}     

     m_numberButtons++;

}

void CToolBar::Show()
{  
SendMessage(m_hToolBar, TB_SETIMAGELIST , (WPARAM)0, (LPARAM)m_hImageList);
SendMessage(m_hToolBar, TB_BUTTONSTRUCTSIZE, sizeof(TBBUTTON), 0);//message for backward 
//compatibility
SendMessage(m_hToolBar, TB_ADDBUTTONS, m_numberButtons, (LPARAM)m_Tbb);   
SendMessage(m_hToolBar,WM_SIZE,0,0);

ShowWindow(m_hToolBar, SW_SHOW);
}

How i used the class
in main.cpp, i created a global instance of the class.

CToolBar myToolBar;

*in the callback procedure, under WM_CREATE, I used some memberfunctions.*

case WM_CREATE:
     myToolBar.Initialise(g_hInst,hwnd);
     myToolBar.AddButton(IDI_OPEN, ID_OPEN);
     myToolBar.AddButton(IDI_MAIN,ID_OPEN);//Separator button
     myToolBar.AddButton(IDI_CLOSE, ID_CLOSE);
     myToolBar.AddButton(IDI_CLOSEALL, ID_CLOSE);
     myToolBar.Show();
     break;

Thats about it.

                                      from Dr Deo

Answer 1

Looks like you are using bitmap with transparency channel. GDI does not support alpha channel. It uses special color which will be transparent. If you want to support 32-bit bitmaps you could use GDI+ for drawing such bitmaps. Another option is to use CAplhaToolbar which already supports bitmaps with alpha transparency.

Answer 2

Try modifying the flags parameter of ImageList_Create to include ILC_MASK as well