Codejock Developer Community : [solved] v17 Flickering buttons in status bar

Author: Dan
Subject: 22891
Posted: 11 February 2016 at 10:39am

Hi,

After upgrading from v16.3.1 to v17, the CXTPButton sub-classed buttons on the status-bar of our application have started to flicker (going from their unpressed state to pressed state) as you move the mouse around.

Each of these buttons have command update handlers which are called during idle processing time to make sure they have the correct state. e.g. something like...

void CMainFrame::OnUpdateUtilsParallelto(CCmdUI* pCmdUI)

{

pCmdUI->Enable(allow_snap);

pCmdUI->SetCheck(current_snap_type() == SNAP_PARALLEL);

}

I think the problem is related to this new code in XTPButton.cpp (introduced since v16.3.1)...

LRESULT CXTPButton::OnSetCheck(WPARAM wParam, LPARAM /*lParam*/)

{

BOOL bVisible = GetStyle() & WS_VISIBLE;

if (bVisible) ModifyStyle(WS_VISIBLE, 0);

Default();

if (bVisible) ModifyStyle(0, WS_VISIBLE);

if (IsPushButton())

{

SetChecked(!GetChecked());

}

...

The line in bold seems to assume that because a button is a push button that calling OnSetCheck should toggle the state, when in fact, the wParam parameter indicates the desired state which could be the same as it was previously.

Changing that line to...

SetChecked(wParam==BST_CHECKED);

Fixes the problem for our application.

Dan

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