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Hi,

I have tried using CExtScrollBar in my application and found a stange behavior. Therefore, I checked with your bitmap editor example, and found this behavior too.

Reproduction steps:
1. Open the Bitmap Editor example, and zoom some area. (Just to let the application show the scrollbars.)
2. Press a scrollbar and drag to its maximum position, and release it.
3. Begin drag the scrollbar from that position to its beyond position. Ex. if you are trying to drag a horizontol scrollbar, drag it to the right direction.

I found that the scollbar lose the focus from mouse. Is this a normal behaviour?

Regards,
Roongrit C.

Thank you for this message. Please update the source code of the CExtScrollBar::OnLButtonDblClk() method in the ExtScrollWnd.cpp class to fix the problem:

void CExtScrollBar::OnLButtonDblClk(UINT nFlags, CPoint point)
{
    ASSERT_VALID( this );
    if( ! m_bCompleteRepaint )
    {
        CScrollBar::OnLButtonDblClk( nFlags, point );
        return;
    }
    // this line fixes unprocessed double clicks
    // (scroll bar behavior does not need double clicks)
    CExtScrollBar::OnLButtonDown( nFlags, point );
}

This code doesn’t solve the problem. I think the cause of this problem should be in OnLButtonDown(...) method, because I didn’t double click on the scrollbar.

Here are the steps again:
1. click on the scrollbar and drag to its maximum position and release the mouse.
--> This should work fine. For a horizontal scrollbar, it will be at far right.
2. "click" on the scrollbar again, and try to drag in the right direction (without release the mouse).
--> Now, the scollbar loses focus. I believe that the scrollbar shouldn’t lose focus until we release the mouse, right?

We confirm this problem but it seems not to be critical. We are working on the fix now.