Customising a dynamic layout at runtime based on control visibility - mfc

Question

I have a multi-purpose CDialog that supports resizing. It can display content in 3 variations.
Variation 1:
Variation 2:
Variation 3:
The dialogue controls are using the dynamic layout settings from the resource editor.
Variation 1 is fine and need no changes.
Variation 2 does not display the combo and date button. As a result I would like the "Text will ..." label to be down at the bottom and the "edit" box to be taller.
Variation 3 has a similar issue where the date button should move to the bottom and the edit box be taller.
Can this be achieved by changing the dynamic layout in code?
Update
I tried this in OnInitDialog:
if (!m_bShowWeekCombo)
{
CRect rctCombo;
m_cbWeek.GetWindowRect(rctCombo);
ScreenToClient(rctCombo);
CRect rctNote;
m_staticInfo.GetWindowRect(rctNote);
ScreenToClient(rctNote);
m_staticInfo.MoveWindow(rctCombo.left, rctCombo.top, rctNote.Width(), rctNote.Height());
}
At first I thought it was working:
The note is now at the bottom. But as soon as I resize the window:
The note has reverted to the original position.
I know I have this answer to a similar issue but do I really have to re-build the whole layout?
Update 2
if (!m_bShowWeekCombo)
{
CRect rctEdit;
m_editText.GetWindowRect(rctEdit);
ScreenToClient(rctEdit);
CRect rctCombo;
m_cbWeek.GetWindowRect(rctCombo);
ScreenToClient(rctCombo);
CRect rctNote;
m_staticInfo.GetWindowRect(rctNote);
ScreenToClient(rctNote);
//m_staticInfo.MoveWindow(rctCombo.left, rctCombo.top, rctNote.Width(), rctNote.Height());
m_staticInfo.SetWindowPos(NULL, rctCombo.left, rctCombo.top, 0, 0,
SWP_NOSIZE | SWP_NOZORDER);
m_editText.SetWindowPos(NULL, 0, 0, rctEdit.Width(), rctEdit.Height() + (rctCombo.top - rctNote.top),
SWP_NOMOVE | SWP_NOZORDER);
if (m_pDynamicLayout)
{
if (!m_pDynamicLayout->HasItem(m_staticInfo.m_hWnd))
{
m_pDynamicLayout->AddItem(m_staticInfo.m_hWnd,
CMFCDynamicLayout::MoveVertical(100), CMFCDynamicLayout::SizeHorizontal(100));
}
else
{
TRACE(L"item already has dynamic move/size\n");
}
if (!m_pDynamicLayout->HasItem(m_editText.m_hWnd))
{
m_pDynamicLayout->AddItem(m_editText.m_hWnd,
CMFCDynamicLayout::MoveNone(), CMFCDynamicLayout::SizeHorizontalAndVertical(100, 100));
}
else
{
TRACE(L"item already has dynamic move/size\n");
}
}
}
When I try the above the control width is the original width, even though the dialog had restored to wider dialog width.

Answer 1

CMFCDynamicLayout reads the dialog resource, it stores the coordinates for the child controls as well as their dynamic resize/move properties.
This is all done in CDialog::OnInitDialog. If you move the child control, example, m_staticInfo then CMFCDynamicLayout doesn't know you moved/resized the control. So upon the next dialog resize request, CMFCDynamicLayout uses the old values.
You can add dynamic resize/move for all controls expcept m_staticInfo and other controls which you intend to move manually. Then add m_staticInfo separately:
BOOL CMyDialog::OnInitDialog()
{
CDialog::OnInitDialog();
CRect rctCombo;
m_cbWeek.GetWindowRect(rctCombo);
ScreenToClient(rctCombo);
m_staticInfo.SetWindowPos(NULL, rctCombo.left, rctCombo.top, 0, 0,
SWP_NOSIZE | SWP_NOZORDER);
if(m_pDynamicLayout)
{
if(!m_pDynamicLayout->HasItem(m_staticInfo.m_hWnd))
{
m_pDynamicLayout->AddItem(m_staticInfo.m_hWnd,
CMFCDynamicLayout::MoveVertical(100), CMFCDynamicLayout::SizeNone());
}
else
{
TRACE(L"item already has dynamic move/size\n");
AfxDebugBreak(0);
}
}
return 1;
}
Internally, MFC calls LoadDynamicLayoutResource(m_lpszTemplateName) to initialize dynamic size/move. But documentation says not to use this method directly.
Clarification
If you are using a dialog that supports resizing then you must remember to calculate the new width and height when you move the control to the new position. You would then use one of the appropriate Size calls. For example:
// The EDIT control height now needs increasing
iNewEditHeight = rctButton.top - iTextMarginY - rctEdit.top;
m_editText.SetWindowPos(nullptr, 0, 0, iNewWidth, iNewEditHeight, SWP_NOMOVE | SWP_NOZORDER);
It is up to you to workout how you want your control initially re-sized.
Then, in OnInitDialog I called a new method:
void CEditTextDlg::SetupDynamicLayout()
{
if (m_pDynamicLayout != nullptr)
{
m_pDynamicLayout->AddItem(IDC_BUTTON_INSERT_DATE,
CMFCDynamicLayout::MoveHorizontalAndVertical(100, 100), CMFCDynamicLayout::SizeNone());
m_pDynamicLayout->AddItem(IDC_STATIC_INFO,
CMFCDynamicLayout::MoveVertical(100), CMFCDynamicLayout::SizeHorizontal(100));
m_pDynamicLayout->AddItem(IDC_EDIT_TEXT,
CMFCDynamicLayout::MoveNone(), CMFCDynamicLayout::SizeHorizontalAndVertical(100, 100));
}
}
If you don't set the width correctly when using SetWindowPos and only use SizeNone() it will not resize correctly.