Forum

Hi all,

I have a MDI app, and am using a CFormView with some controls anchored as described in this forum, the problem is everytime I switch from on view to other, the controls flicker from the original size/position to the new ones. How can I avoid this to happen? BTW I’m using MDITabs to switch between view/documents.

Thanks in advance.

Dear Sergio,

We are sorry, but there is not enough information in your message to come to any conclusion about the problem you described. Could you send us a test project that reproduces this problem or, at least,the source code of your form view class?

View class declaration:

class CMyView : public CExtWA < CExtWS < CExtAFV < CFormView > > >
{
protected: // create from serialization only
   CMyView();
   DECLARE_DYNCREATE(CMyView)
 
public:
   //{{AFX_DATA(CMyView)
   enum { IDD = IDD_MYVIEW_FORM };
   CExtGroupBox  m_grpGroupBox1;
   CExtLabel	 m_lblLabel1;
   CExtEdit	  m_edtEdit1;
   CExtLabel	 m_lblLabel2;
   CExtEdit	  m_edtEdit2;
   CExtGroupBox  m_grpGroupBox2;
   //}}AFX_DATA
   CExtGridWnd   m_grdGrid;
 
// Attributes
public:
   CMyDoc* GetDocument();
 
// Operations
protected:
   void InitGrid();
 
// Overrides
   // ClassWizard generated virtual function overrides
   //{{AFX_VIRTUAL(CMyView)
   public:
   virtual BOOL PreCreateWindow(CREATESTRUCT& cs);
   protected:
   virtual void DoDataExchange(CDataExchange* pDX);    // DDX/DDV support
   virtual void OnInitialUpdate(); // called first time after construct
   virtual void OnUpdate(CView* pSender, LPARAM lHint, CObject* pHint);
   //}}AFX_VIRTUAL
 
// Implementation
public:
   virtual ~CMyView();
#ifdef _DEBUG
   virtual void AssertValid() const;
   virtual void Dump(CDumpContext& dc) const;
#endif
 
protected:
 
// Generated message map functions
protected:
   //{{AFX_MSG(CPalmROMEditorView)
   afx_msg void OnSize(UINT nType, int cx, int cy);
   //}}AFX_MSG
   DECLARE_MESSAGE_MAP()
};

 View class implementation:

void CMyView::OnInitialUpdate()
{
   CFormView::OnInitialUpdate();
 
   AddAnchor(IDC_GROUPBOX1, __RDA_KEEP, __RDA_X);
   AddAnchor(IDC_GROUPBOX2, __RDA_KEEP, __RDA_BOTH);
 
   ShowSizeGrip(FALSE);
}
 
void CMyView::InitGrid()
{
   static INT arrHdrExtents[] = { 150, 50, 50, 100 };
   static LPCTSTR arrHdrTexts[] = { _T("Column1"), _T("Column2"), _T("Column3"),
	  _T("Column4") };
 
   m_grdGrid.SiwModifyStyle(__ESIW_ST_ITEM | __EGBS_FIXED_SIZE_ROWS |
	  __EGBS_SFB_CELLS | __EGBS_RESIZING_CELLS_OUTER_H |
	  __EGBS_DYNAMIC_RESIZING_H);
 
   m_grdGrid.OuterRowCountTopSet(1, false);
   m_grdGrid.ColumnAdd(4, false);
 
   for (LONG n = 0; n < 4; n++)
   {
	  CExtGridCellHeader* pCell = STATIC_DOWNCAST(CExtGridCellHeader,
		 m_grdGrid.GridCellGetOuterAtTop(n, 0,
		 RUNTIME_CLASS(CExtGridCellHeader)));
	  pCell->ExtentSet(arrHdrExtents[n]);
	  pCell->TextSet(arrHdrTexts[n]);
   }
}
 
void CMyView::OnUpdate(CView* pSender, LPARAM lHint, CObject* pHint) 
{
   if (m_grdGrid.ColumnCountGet() == 0)
	  InitGrid();
 
   CMyDoc* pDocument = GetDocument();
 
   m_edtEdit1.SetWindowText(pDocument->GetData1());
   m_edtEdit2.SetWindowText(pDocument->GetData2());
 
   LONG numRows = pDocument->GetNumRows();
 
   m_grdGrid.RowRemoveAll(false);
   m_grdGrid.RowAdd(numRows, false);
 
   for (LONG index = 0; index < numRows; index++)
   {
	  CExtGridCellStringDM* pCell = STATIC_DOWNCAST(CExtGridCellStringDM,
		 m_grdGrid.GridCellGet(0, index, 0, 0,
		 RUNTIME_CLASS(CExtGridCellStringDM)));
	  pCell->TextSet(pDocument->GetCol0(index));
   }
 
   m_grdGrid.OnSwUpdateScrollBars();
   m_grdGrid.OnSwDoRedraw();
}
 
void CMyView::OnSize(UINT nType, int cx, int cy) 
{
   CWnd::OnSize(nType, cx, cy);
}

Your source code looks correct. We may guess that you forgot to set on the "Clip children" option in the dialog resource.

As for the problem with scrollbars, please replace the following code in the CMyView::InitGrid() method

m_grdGrid.SiwModifyStyle(
    __ESIW_ST_ITEM 
        | __EGBS_FIXED_SIZE_ROWS
        | __EGBS_SFB_CELLS
        | __EGBS_RESIZING_CELLS_OUTER_H
        | __EGBS_DYNAMIC_RESIZING_H
);

m_grdGrid.SiwModifyStyle(
    __ESIS_STH_ITEM | __ESIS_STV_ITEM
        | __EGBS_FIXED_SIZE_ROWS
        | __EGBS_SFB_CELLS
        | __EGBS_RESIZING_CELLS_OUTER_H
        | __EGBS_DYNAMIC_RESIZING_H
);

I have set the Clip Children option, but then the controls inside the group boxes are not displayed when the first document is opened, when opening another document all the controls are correctly displayed on both views, but the flickering is still there, any other hint?

You should move the group box back in Z-order to see the controls "inside" it (of course, in fact, they are over it). We have no idea about flickering. If you send us your project, we will fix this problem.

Hi again,

I have already solved the problem with the grid scrollbars, I didn’t set correctly the style when calling SiwModifyStyle, but I’m still having the flickering problem.

Could you send us your project? We believe that this will clarify this problem.