Detecting clicks outside of widgets while still having widgets deal with keypresses that occur within them.

TrolliOlli

I'm trying to make a basic application that lets you click in two locations to define a line (e.g. I click at point (0,0) and point (10, 10) and a line is drawn between those two points).

Additionally, I'd like to have a rectangle widget that I can click and drag around.

I already have the rectangle working correctly, but now I'm running into issues detecting keyPresses in the main view.

I have a custom class that inherits from QGraphicsView and overrides the following methods:
void mousePressEvent(QMouseEvent *event);
void mouseMoveEvent(QMouseEvent *event);
void mouseReleaseEvent(QMouseEvent *event);

When I implement these methods however, my program completely ignores the mousePressEvent methods I have within my rectangle class (as they are all caught by these methods first).

Is there a way to catch clicks within my view ONLY when they're not inside a widget (otherwise catch them within the widget)?

SGaist

Hi and welcome to devnet,

Are you calling the base class implementation of these methods in your reimplementation ?

TrolliOlli

@SGaist

I don't believe so.

In MyView I have:

void MyView::mousePressEvent(QMouseEvent *event)
{
std::cout << "CLICKED IN VIEW\n" << std::endl;
}

and in MyRectangle I have:
void MyRectangle::mousePressEvent(QGraphicsSceneMouseEvent *event)
{
std::cout << "CLICKED IN Rectangle!\n" << std::endl;
}

Currently all clicks are printing "CLICKED IN VIEW", even if it's actually inside the rectangle.

TrolliOlli

Bump. I still can't figure this out.

The best way I can figure to do it currently is keep a list of MyRectangle's inside MyView and then manually pass the event like so:

void MyView::mousePressEvent(QMouseEvent *event)
{
    std::cout << "CLICKED IN VIEW\n" << std::endl;

    for (std::vector<MyRectangle*>::iterator it = rectangles.begin(); it != rectangles.end(); ++it)
    {
 	
	    ((MyRectangle*)*it)->mousePressEvent(event);
	
    }
}

this seems really barbaric though and I'm hoping there's just some way to do something like passEventToChildren(event)

SGaist

Again: you are not calling the base class implementation, so you are interrupting the normal event delivery.

void MyView::mousePressEvent(QMouseEvent *event){
    qDebug() << "Clicked in view";
    QGraphicsView::mousePressEvent(event);
}

TrolliOlli

@SGaist said:

Again: you are not calling the base class implementation, so you are interrupting the normal event delivery.
void MyView::mousePressEvent(QMouseEvent *event){
    qDebug() << "Clicked in view";
    QGraphicsView::mousePressEvent(event);
}

This worked perfectly. Sorry, I thought you were making sure I WASN'T calling the base class implementation.

SGaist

No problem :)

Since you have it working now, please update the thread title prepending [solved] so other forum users may know a solution has been found :)