How can to change the QGraphicsTextItem 's cursor width?

[robertkun]

Hello ,
I am using a QGraphicsTextItem ,but the cursor in it is too thin to find it .
And I Find the QGraphicsTextItem doesn't supports the method of " setCursorWidth( ) ".

Does anybody know how to change it tell me please.
Thanks.

[robertkun]

#include "cgTextItem.h"
#include <QPlainTextDocumentLayout>


cgTextItem::cgTextItem(QGraphicsItem *parent, QGraphicsScene *scene)
:QGraphicsTextItem(parent, scene)
{
QFont newFont = font();
newFont.setPointSize(24);
setFont(newFont);

setDefaultTextColor(Qt::blue);

QPlainTextDocumentLayout *plainLayout = new QPlainTextDocumentLayout(document());
plainLayout->setCursorWidth(100);

document()->setDocumentLayout(plainLayout);

setFlag(QGraphicsItem::ItemIsMovable,true);
setFlag(QGraphicsItem::ItemIsSelectable,true);
setTextInteractionFlags(Qt::TextEditorInteraction) ;

setPlainText("New Item");
}

this is my construct function ,the QPlainTextDocumentLayout have a function setCursorWidth can be change the cursor width in the QGraphicsTextItem ,
but the effect is not good,it becomed very small. I don't know the reason .can you help me ?

And changed the setCursorWidth's value ,the effect is still .