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Hello.

A grid is slow

I add 200 lines to a grid.

Then I do a selection of all lines of the grid.

When I let a grid scroll, scroll is abnormally slow. 

Yes. It’s slow. You are added too many rectangles into the selection region. This is the same as to select manually a lot of rows by clicking on each of them while Ctrl key is pressed. This will never occur in the real life because nobody will select 200 rows via 200 mouse clicks. If you select the first row and press Shfit+End keys, then all the rows become selected and selection region contains only one rectangle. As a result, the grid works fast. If you need to compose selection of many grid rows programmatically, then your code should combine selection rectangles to minimize the number of rectangles in the selection region.

>This will never occur in the real life because nobody will select 200 rows via 200 mouse clicks.

It is to be possible programmatically.

After having executed the following processing.

I want a command optimizing a cell range.

void CSampleMuGridDlg::OnButton2() 
{
    POINT  pt;
    int iRow;
    for ( iRow = 0 ; iRow < m_pMuMlGrid->RowCountGet() ; iRow++ ){
     pt.x = -1;
     pt.y = iRow;
  m_pMuMlGrid->Selection1Line( pt , true );
 }
}
bool CNxL_MlGrid::Selection1Line(
    POINT  pt,
    bool blFlag
    )
{
    if ( blFlag == true ){
	    if ( SelectionGetForCell( -1, pt.y ) == false ){
		    SelectionSet( pt , false );
	    }
    }else{
	    if ( SelectionGetForCell( -1, pt.y ) == true ){
		    SelectionSet( pt , false );
	    }
    }
    return true;
}

We have grids with 200 and more lines in our sample projects provided with Prof-UIS. They scroll OK. We need to know how you initialize your grid control? It would be very interesting to debug this issue using your test project.

When I execute scroll in the following procedures

Such a phenomenon occurs.

http://ifreeta.dee.cc/20090926/SampleMuGrid200904.lzh

please download it