Pressing Child Widgets

sandro4912

Ok i have the following:

A Class Minefield which has Cells as Childs.

class Minefield : public QWidget
{
    Q_OBJECT
//....
private:
    QVector<Cell *> mCells;
    CellInputHandler *mCellInputHandler;

All Clicks etc get handled from CellInputHandler which is a child as well:

// In Minefield Constructor:
for(auto &cell : mCells) {
        cell->installEventFilter(mCellInputHandler);
    }

Now i want to click on a Cell to test if a signal gets emitted. I have a test like this:

    QVector<Cell *> cells;

    cells << new Cell{ Cell::State::empty };
    cells << new Cell{ Cell::State::mine };

    cells << new Cell{ Cell::State::mine };
    cells << new Cell{ Cell::State::empty };

    constexpr auto height = 2;
    constexpr auto width = 2;

    auto cellWidth = cells[0]->width();
    auto cellHeight = cells[0]->height();

    Minefield obj{ cells, width, height };

    QSignalSpy spy(&obj, &Minefield::uncoveredFirstCell);

    QPoint pos = {obj.pos().x() + cellWidth/2,
            obj.pos().y() + cellHeight/2};

    auto child = obj.childAt(pos);  // I checked here that theres actually a child

    QTest::mousePress(&obj, Qt::LeftButton, Qt::NoModifier, pos);
    QTest::qWait(delayClickRightAndLeftTogether);
    QTest::mouseRelease(&obj, Qt::LeftButton, Qt::NoModifier, pos);

    QCOMPARE(spy.count(), 1);

So theres a Cell at pos. But why i cannot click from the Parent like this:

    QTest::mousePress(&obj, Qt::LeftButton, Qt::NoModifier, pos);
    QTest::qWait(delayClickRightAndLeftTogether);
    QTest::mouseRelease(&obj, Qt::LeftButton, Qt::NoModifier, pos);

I checked with the debugger any event code from the CellInputHandler is never hit.

I already tested the Cellclass alone together with its CellInputHandler and could always click on a Cell like this.

sandro4912

I override for test mousePressEvent of Minefield:

void Minefield::mousePressEvent(QMouseEvent *event)
{
    QWidget::mousePressEvent(event);
}

I can see in the Debugger that it jumps into the mousePressEvent when I do the press the test.

Then I would expect it would hit the installed Event filter CellInputHandler but it never happens:

bool CellInputHandler::eventFilter(QObject *watched, QEvent *event)
{
    if(event->type() == QEvent::MouseButtonPress){       
       handleMouseButtonPressEvents(watched, event);
       return true;
    }
    if(event->type() == QEvent::MouseButtonRelease){      
        handleMouseButtonReleaseEvents(watched, event);
       return true;
    }
    if(event->type() == QEvent::MouseMove) {
        handleMouseMoveEvents(event);
        return true;
    }
    return false;
}

So in short I expect the following:

Clicking on Minefield at the pos were is a Cell.
Minefield forwards the event to Cell. Since Cell has a event filter installed it should forward to it.

But it does not happen. Why?

mrjj

@sandro4912 said in Pressing Child Widgets:

QTest::mousePress

hi
It's only when using the QTest function the event filter is not triggered ?
Meaning, actual real clicking on it work as expected ?

My guess would be that QTest::mouseXXX synthesizes the corresponding Qt event directly and also send it directly to the widget you give as the parameter. However, i didnt check the source code if that is indeed the case.

sandro4912

@mrjj

yes the application works if i run it as expected. i just wanted to add tests to verify. Maybe its a good idea to investigate the source code of the test framework for mouse press.

sandro4912

The Code for the mousepress can be found here:

https://code.woboq.org/qt5/qtbase/src/testlib/qtestmouse.h.html

It looks like they use a class QWindowSystemInterface to handle all the mouse events.

Is there annother way to simulate a click on the widget?