How to set the decoration hightlighted when select a row in QTreeView

[lovehouye]

I use delegate to draw the rows.
In paint function:

if( option.state & QStyle::State_Selected )
    {
        QRect rect( option.rect );
        rect.setLeft( 0 );
        painter->fillRect( rect, option.palette.highlight() );
    }

if( option.state & QStyle::State_Selected )
    {
        QRect rect( option.rect );
        rect.setLeft( 0 );
        painter->fillRect( rect, option.palette.highlight() );
    }

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For this, all the area can be highlighted. But overwritted decoration can't be shown. Maybe the color of decoration should be changed when selected.