Show grey level value of pixel in Qt when the mouse is over it

[^NyAw^]

Hi,

You have to create a class that inherits from QGraphicsItem(in your case QGraphicsPixmapItem). Then redefine the "mouseMoveEvent" method on this class.

class MyPixmapItem : public QGraphicsPixmapItem
...
...
void mouseMoveEvent()
{
  // your code here
}

class MyPixmapItem : public QGraphicsPixmapItem
...
...
void mouseMoveEvent()
{
  // your code here
}

To copy to clipboard, switch view to plain text mode 

Also you will need to connect some kind of SIGNALs and SLOTs from MyPixmapItem to the main window if you want to show the gray value into a QLabel or QSpinBox(just an example).

When you add the Item in the scene you have to create an object of this class instead of the base class

This:

scene->addPixmap(pix);

scene->addPixmap(pix);

To copy to clipboard, switch view to plain text mode 

Have to be something like this:

MyPixmapItem *item = new MyPixmapItem();
myScene->addItem(item);

MyPixmapItem *item = new MyPixmapItem();
myScene->addItem(item);

To copy to clipboard, switch view to plain text mode