A TXPBAR with GDI+ for MFC

• Download source code - 3.4 MB

Introduction

This is an XP dockbar program like Apple's dockbar. It switches scrolling with a flip animation effect.

Using the code

Step 1. This step inludes loading the library "User32.DLL" for the "UpdateLayeredWindow" function. This is a per-pixel-alpha transparence. Therefore, we have no more jagged edges.

hFuncInst = LoadLibrary("User32.DLL"); 
BOOL bRet=FALSE;
if(hFuncInst){ 
    UpdateLayeredWindow=(MYFUNC)GetProcAddress(hFuncInst, "UpdateLayeredWindow");
}
else
{
    AfxMessageBox("User32.dll ERROR!");
    exit(0);
}

Step 2. Initialize GDI+.

m_Blend.BlendOp=0; //the only BlendOp defined in Windows2000
m_Blend.BlendFlags=0; //nothing else isspecial...
m_Blend.AlphaFormat=1;
m_Blend.SourceConstantAlpha=255;//AC_SRC_ALPHA

Step 3. Now, the DrawTXBar function.

void DrawTXBar()
{
    DWORD dwExStyle=GetWindowLong(m_hWnd,GWL_EXSTYLE);
    if((dwExStyle&0x80000)!=0x80000)
    SetWindowLong(m_hWnd,GWL_EXSTYLE,dwExStyle^0x80000);
    BOOL bRet=FALSE;
    bRet= UpdateLayeredWindow( m_hWnd,hdcScreen,&ptWinPos, 
          &sizeWindow,m_hdcMemory,&ptSrc,0,&m_Blend,2);
    //UpdateLayeredWindow" must By execute 
    //one hypo- one to Update the alpha window's Image.
    ...
}

Points of interest

The API function "UpdateLayeredWindow" must by executed to update the alpha window's image.

This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)