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Hi, I have a CExtGridCellString, and want to dynamically change its text. I got a pointer to the cell using ValueActiveGet(), and then set the text using TextSet(). However, the text doesn’t update! I am wondering if I’m supposed to explicitly redraw the window, and if so, what method do I call?

You need to explicitly redraw the property grid window when you change cell values programmatically:

m_PGC.OnSwUpdateScrollBars();
m_PGC.OnSwDoRedraw();

Hi, thanks... just to clarify for other here, the actual call from a property grid ctrl subclass is:

GetActiveGrid()->OnSwUpdateScrollBars();
GetActiveGrid()->OnSwDoRedraw();

CExtPropertyCategory* pCategory = static_cast<CExtPropertyCategory*>(store.ItemGetAt( 0));
int numProperties = pCategory->ItemGetCount();
for( int i=0; i<numProperties; i++) {
    CExtPropertyItem* pItem = pCategory->ItemGetAt( i);
    string name = pItem->NameGet();
    if( name != "donut with sprinkles")
        continue;
    CExtGridCellString* pCell = dynamic_cast<CExtGridCellString*>(pItem->ValueActiveGet());
    pCell->TextSet( editboxes[name].c_str());  // the editboxes[name] is just a dynamically generated name
}
GetActiveGrid()->OnSwUpdateScrollBars();
GetActiveGrid()->OnSwDoRedraw();

The CExtPropertyValue class contains two CExtGridCell objects describing the active and default values of a property. Your code gets a pointer to the active value cell and changes it absolutely correctly. But the grid windows inside the property grid control contains copies of the grid cell objects being modified by your code and the property grid control needs to be synchronized with the CExtPropertyGridCtrl::PropertyStoreSynchronize() method. Alternatively you can traverse all the grid windows inside the property grid control, find the cell objects corresponding to the property value and modify them:

CExtPropertyGridCtrl & _PGC = . . .
CExtPropertyValue * pValue = . . .
CTypedPtrArray < CPtrArray, CExtPropertyGridWnd * > arrGrids;
    _PGC.OnPgcQueryGrids( arrGrids );
INT nGridIdx = 0;
    for( ; nGridIdx < arrGrids.GetSize(); nGridIdx ++ )
    {
        CExtPropertyGridWnd * pGrid = arrGrids[ nGridIdx ];
        ASSERT_VALID( pGrid );
        HTREEITEM hTreeItem =
            pGrid->PropertyItemToTreeItem( pValue );
        if( hTreeItem == NULL )
            continue;
        CExtGridCell * pCell =
            pGrid->ItemGetCell( hTreeItem, 1 );
        if( pCell == NULL )
            continue; 
        ASSERT_VALID( pCell );
        pCell->TextSet( . . . );
        // REDRAW MODIFIED CELL ONLY:
        if( (pGrid->GetStyle()&WS_VISIBLE) == 0 )
            continue;
        LONG nPlainIndex =
            pGrid->ItemGetVisibleIndexOf( hTreeItem );
        if( nPlainIndex < 0 )
            continue;
        CRect rc;
        pGrid->GridCellRectsGet(
            1, nPlainIndex, 0, 0, NULL, &rc );
        pGrid->InvalidateRect( &rc );
        pGrid->UpdateWindow();
    } // for( ; nGridIdx < arrGrids.GetSize(); nGridIdx ++ )