MFC : accessing CMainFrame's CImageList from ChildView

Question

I'm trying to add images to imagelist of toolbar, which is a member of CMainFrame

startStopPicture.LoadBitmapW(IDB_STOP_PIC);
m_ToolBar.GetToolBarCtrl().GetImageList()->Add(&startStopPicture, reinterpret_cast<CBitmap*>(NULL)); 

startStopPicture.DeleteObject();

startStopPicture.LoadBitmapW(IDB_START_PIC);
m_ToolBar.GetToolBarCtrl().GetImageList()->Add(&startStopPicture, reinterpret_cast<CBitmap*>(NULL));

then I need to access this imagelist from childview. I'm trying do to it like this

CMainFrame* mainFrame = dynamic_cast<CMainFrame*>(GetParentFrame());

CImageList* imList = mainFrame->m_ToolBar.GetToolBarCtrl().GetImageList();

But those images I added in the mainframe's method are absent now. How to solve this promlem?

When you need the image list in the child, create one in this class. It is bad design to access such members accross classes. — xMRi, Aug 12 '15 at 06:19

score 1 · Accepted Answer · answered Aug 12 '15 at 06:34

I assume your CBitmap startStopPicture is a local variable, since you neither mentioned otherwise or preceded the variable name with any class-like-identifier. Afterwards you try to store via CImageList::Add a local variable by reference.

What you have to do is either allocating the CBitmap - new CBitmap or add the startStopPicture variable to your class as a member.

If you choose to allocate the variable and do not have to keep track of the CBitmap, you could use a std::vector<std::unique_ptr<CBitmap> > as class-member.

If you store a local variable CBitmap in a CImageList, the image will not display.

Example:

//class declaration
private:
    std::vector<std::unique_ptr<CBitmap> > m_vLoadedBitmaps;
};

void CMyCtrl::SetBitmaps(CImageList &imgList)
{
    CBitmap *bmpDelete = new CBitmap();
    bmpDelete->LoadBitmapW(IDB_DELETE);
    m_vLoadedBitmaps.push_back(std::unique_ptr<CBitmap>(bmpDelete));

    imgList.Add(bmpDelete, static_cast<CBitmap*>(NULL));
}

Also I would recommend loading the images in the owner class of the variable. If needed, there's still SendMessage.

Exactly what i need :) thanx! – goodking Aug 12 '15 at 15:39 — goodking, Aug 12 '15 at 15:39

MFC : accessing CMainFrame's CImageList from ChildView

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