QGraphicsTextItem bug on mouse interaction?

**mooreaa** · 3rd July 2008, 13:32

I found a fairly big bug with QGraphicsTextItem. Maybe someone can reproduce before I submit a bug report? Also where do I report bugs again?

Qt Code:

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#include <QApplication>
#include <QGraphicsRectItem>
#include <QGraphicsTextItem>
#include <QGraphicsScene>
#include <QGraphicsView>
 
int main(int argc, char *argv[])
{
	QApplication a(argc, argv);
	QGraphicsScene scene;
 
	QGraphicsRectItem* rect = new QGraphicsRectItem(QRectF(25,25,120,80),0,&scene);
	rect->setFlag(QGraphicsItem::ItemIsMovable, true);
	rect->setFlag(QGraphicsItem::ItemIsSelectable, true);
	rect->acceptHoverEvents();
 
	QGraphicsTextItem* text = new QGraphicsTextItem("ABCDEFGHIJKLMNOP",rect,&scene);
	text->setTextInteractionFlags( Qt::TextEditorInteraction );
 
	QGraphicsView view;
	view.setScene( &scene );
	view.setDragMode( QGraphicsView::RubberBandDrag );
	view.show();
 
	return a.exec();
}

#include <QApplication>
#include <QGraphicsRectItem>
#include <QGraphicsTextItem>
#include <QGraphicsScene>
#include <QGraphicsView>

int main(int argc, char *argv[])
{
	QApplication a(argc, argv);
	QGraphicsScene scene;

	QGraphicsRectItem* rect = new QGraphicsRectItem(QRectF(25,25,120,80),0,&scene);
	rect->setFlag(QGraphicsItem::ItemIsMovable, true);
	rect->setFlag(QGraphicsItem::ItemIsSelectable, true);
	rect->acceptHoverEvents();

	QGraphicsTextItem* text = new QGraphicsTextItem("ABCDEFGHIJKLMNOP",rect,&scene);
	text->setTextInteractionFlags( Qt::TextEditorInteraction );
	
	QGraphicsView view;
	view.setScene( &scene );
	view.setDragMode( QGraphicsView::RubberBandDrag );
	view.show();

	return a.exec();
}

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Run, select some text, now click on the dotted border of the edit text item.

Mouse interaction stops working.

I tried subclassing it and tried a few things with onmousepress events and such but wasn't able to fix this sucker.

Can someone else confirm this? And possibly a workaround!?!

**patrik08** · 3rd July 2008, 15:46

Originally Posted by mooreaa

I found a fairly big bug with QGraphicsTextItem. Maybe someone can reproduce before I submit a bug report? Also where do I report bugs again?
Mouse interaction stops working.
I tried subclassing it and tried a few things with onmousepress events and such but wasn't able to fix this sucker.

Can someone else confirm this? And possibly a workaround!?!

this is not a bug if focus is lost the cursor not repaint....

if you like permanent edit and cursor blink test this...

Qt Code:

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#include <QApplication>
#include <QGraphicsRectItem>
#include <QGraphicsTextItem>
#include <QGraphicsScene>
#include <QGraphicsView>
#include <QAbstractTextDocumentLayout>
#include <QBasicTimer>
class TextDia : public QGraphicsTextItem
{
   Q_OBJECT 
 
public:
	TextDia::TextDia( const QString txt , 
                   QGraphicsItem *parent , 
                   QGraphicsScene *scene )
  : QGraphicsTextItem(txt,parent,scene),
    cursorTime(false),BackHightlight(QColor("#a6ffc7")) {
		setBlinkingCursorEnabled(true);
		BackHightlight.setAlpha(80);
		}
 
	QRectF boundingRect() const
  {
   return document()->documentLayout()->frameBoundingRect(document()->rootFrame());
  }
 
	void setBlinkingCursorEnabled(bool enable)
  {
    cursorTime = false; /* leave cursor not paint */
    if (enable && QApplication::cursorFlashTime() > 0) {
        cursorTimeLine.start( QApplication::cursorFlashTime() / 2,this);
        setTextInteractionFlags ( Qt::TextEditorInteraction );
		}  else {
        cursorTimeLine.stop();
        setTextInteractionFlags ( Qt::NoTextInteraction );
		}
  }
	void timerEvent(QTimerEvent *event)
	{
				if (event->timerId() == cursorTimeLine.timerId()) {
								if (!cursorTime) {
									cursorTime = true; 
								} else {
									cursorTime = false;
								}
								update();
				}
	}
	void paint(QPainter *painter, const QStyleOptionGraphicsItem *option,
                              QWidget *widget)
	{
				Q_UNUSED(widget);
				const int text_cursor_position = textCursor().position();
				painter->save();		 
				QAbstractTextDocumentLayout::PaintContext CTX;    
				CTX.selections;
				painter->setClipRect(boundingRect(), Qt::IntersectClip);
						if (cursorTime) {
							CTX.cursorPosition = text_cursor_position;
						} else {
							CTX.cursorPosition = -1;  
						}
				painter->setPen(Qt::NoPen);
				CTX.clip = boundingRect();
				painter->setBrush(BackHightlight);
		    painter->drawRect(boundingRect());
				document()->documentLayout()->draw(painter,CTX);
				painter->setPen(Qt::NoPen);
				painter->restore();
	}
 
QColor BackHightlight;
QBasicTimer cursorTimeLine;
bool cursorTime;
};
#include "main.moc"
int main(int argc, char *argv[])
{
	QApplication a(argc, argv);
	QGraphicsScene scene;
	QGraphicsRectItem* rect = new QGraphicsRectItem(QRectF(25,25,120,80),0,&scene);
	rect->setFlag(QGraphicsItem::ItemIsMovable, true);
	rect->setFlag(QGraphicsItem::ItemIsSelectable, true);
	rect->acceptHoverEvents();
	TextDia* text = new TextDia("ABCDEFGHIJKLMNOP",rect,&scene);
	QGraphicsView view;
	view.setScene( &scene );
	view.setDragMode( QGraphicsView::RubberBandDrag );
	view.show();
	return a.exec();
}

#include <QApplication>
#include <QGraphicsRectItem>
#include <QGraphicsTextItem>
#include <QGraphicsScene>
#include <QGraphicsView>
#include <QAbstractTextDocumentLayout>
#include <QBasicTimer>
class TextDia : public QGraphicsTextItem
{
   Q_OBJECT 
	
public:
	TextDia::TextDia( const QString txt , 
                   QGraphicsItem *parent , 
                   QGraphicsScene *scene )
  : QGraphicsTextItem(txt,parent,scene),
    cursorTime(false),BackHightlight(QColor("#a6ffc7")) {
		setBlinkingCursorEnabled(true);
		BackHightlight.setAlpha(80);
		}
		
	QRectF boundingRect() const
  {
   return document()->documentLayout()->frameBoundingRect(document()->rootFrame());
  }
	
	void setBlinkingCursorEnabled(bool enable)
  {
    cursorTime = false; /* leave cursor not paint */
    if (enable && QApplication::cursorFlashTime() > 0) {
        cursorTimeLine.start( QApplication::cursorFlashTime() / 2,this);
        setTextInteractionFlags ( Qt::TextEditorInteraction );
		}  else {
        cursorTimeLine.stop();
        setTextInteractionFlags ( Qt::NoTextInteraction );
		}
  }
	void timerEvent(QTimerEvent *event)
	{
				if (event->timerId() == cursorTimeLine.timerId()) {
								if (!cursorTime) {
									cursorTime = true; 
								} else {
									cursorTime = false;
								}
								update();
				}
	}
	void paint(QPainter *painter, const QStyleOptionGraphicsItem *option,
                              QWidget *widget)
	{
				Q_UNUSED(widget);
				const int text_cursor_position = textCursor().position();
				painter->save();		 
				QAbstractTextDocumentLayout::PaintContext CTX;    
				CTX.selections;
				painter->setClipRect(boundingRect(), Qt::IntersectClip);
						if (cursorTime) {
							CTX.cursorPosition = text_cursor_position;
						} else {
							CTX.cursorPosition = -1;  
						}
				painter->setPen(Qt::NoPen);
				CTX.clip = boundingRect();
				painter->setBrush(BackHightlight);
		    painter->drawRect(boundingRect());
				document()->documentLayout()->draw(painter,CTX);
				painter->setPen(Qt::NoPen);
				painter->restore();
	}
	
QColor BackHightlight;
QBasicTimer cursorTimeLine;
bool cursorTime;
};
#include "main.moc"
int main(int argc, char *argv[])
{
	QApplication a(argc, argv);
	QGraphicsScene scene;
	QGraphicsRectItem* rect = new QGraphicsRectItem(QRectF(25,25,120,80),0,&scene);
	rect->setFlag(QGraphicsItem::ItemIsMovable, true);
	rect->setFlag(QGraphicsItem::ItemIsSelectable, true);
	rect->acceptHoverEvents();
	TextDia* text = new TextDia("ABCDEFGHIJKLMNOP",rect,&scene);
	QGraphicsView view;
	view.setScene( &scene );
	view.setDragMode( QGraphicsView::RubberBandDrag );
	view.show();
	return a.exec();
}

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**mooreaa** · 3rd July 2008, 23:14

No its not that i lose focus, its that even when I refocus, my mouse interaction does not work at all.

**patrik08** · 4th July 2008, 07:29

Originally Posted by mooreaa

No its not that i lose focus, its that even when I refocus, my mouse interaction does not work at all.

if I refocus my mouse continue to edit and blink... on your code

Install qt4.4.0 .....

show /Qt/4.4.0_src/examples/graphicsview/diagramscene having a swap to move && edittext

Qt Code:

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void DiagramTextItem::focusOutEvent(QFocusEvent *event)
{
    setTextInteractionFlags(Qt::NoTextInteraction);
    emit lostFocus(this);
    QGraphicsTextItem::focusOutEvent(event);
}
//! [2]
 
//! [5]
void DiagramTextItem::mouseDoubleClickEvent(QGraphicsSceneMouseEvent *event)
{
    if (textInteractionFlags() == Qt::NoTextInteraction)
        setTextInteractionFlags(Qt::TextEditorInteraction);
    QGraphicsTextItem::mouseDoubleClickEvent(event);
}

void DiagramTextItem::focusOutEvent(QFocusEvent *event)
{
    setTextInteractionFlags(Qt::NoTextInteraction);
    emit lostFocus(this);
    QGraphicsTextItem::focusOutEvent(event);
}
//! [2]

//! [5]
void DiagramTextItem::mouseDoubleClickEvent(QGraphicsSceneMouseEvent *event)
{
    if (textInteractionFlags() == Qt::NoTextInteraction)
        setTextInteractionFlags(Qt::TextEditorInteraction);
    QGraphicsTextItem::mouseDoubleClickEvent(event);
}

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IMO my work:
http://www.qt-apps.org/content/show....?content=80234