Simulate left mouse button unclick (release button)

mrjj

well
the drop down part of a combo box is using an event filter. I think its related to this but
not sure. If it works with a real mouse, why not with touch ?

Do you use real touch events or did you tell it to act like a mouse? ( the touch controller)

Well, no harm in trying but I guess it will just be eaten too
QMouseEvent *mEvnRelease = new QMouseEvent(QEvent::MouseButtonRelease, pos, Qt::LeftButton, Qt::LeftButton, Qt::NoModifier);
QCoreApplication::sendEvent(QWidget::focusWidget(),mEvnRelease);

Did you try with other applications?
Anything with a combobox should do the same. :)

Andrey Shmelew

@mrjj
hmmm...

i use yours code:

void MainWindow::mousePressEvent(QMouseEvent* event)
{
    if(event->buttons() == Qt::RightButton)
        ui->label_7->setText("Only right button");
    if(event->buttons() == Qt::LeftButton)
        ui->label_7->setText("Only left button");
    QMouseEvent *mEvnRelease = new QMouseEvent(QEvent::MouseButtonRelease, QCursor::pos(), Qt::LeftButton, Qt::LeftButton, Qt::NoModifier);
    QCoreApplication::sendEvent(QWidget::focusWidget(),mEvnRelease);
}

, it works now better, but even if MouseButtonRelease event exsists, buttons somehow becomes untouchable.

"Do you use real touch events or did you tell it to act like a mouse? ( the touch controller)"

it acts like a mouse (touch controller presents)!

I have uploaded example project with combobox to the device, and there is exactly the same problem.

mrjj

@Andrey-Shmelew
Hmm really sounds like the touch controller is not acting as a mouse and only
sends touch events.

You could set a event filter and watch what events you get.
http://www.informit.com/articles/article.aspx?p=1405544&seqNum=2

also note with the code its sends m up to the focused control so if it was not the
same control that got Mouse Press, it will not work.

Ps. to get names and not ints for the events, you can use
https://www.dropbox.com/s/rujoldiax0cql3z/names.txt?dl=0

Andrey Shmelew

@mrjj

thank you for the link, sir!

i have event handler:

void MainWindow::mouseReleaseEvent(QMouseEvent* event)
{
    ui->label_7->setText("button Released");
}

and touch controller sends this event.

maybe, it sends mouseReleaseEvent properly not every time i when i touch

Andrey Shmelew

i found a bug,
in my project i have a dial control...
firstly i touched to control and manipulated a litlle bit,
then i touched free area (without any controls or widgets) and noticed than dial reacts on my touching and rotates in direct of my touch spot (i did not touch dial but it turned).

mrjj

@Andrey-Shmelew
Well you can check with mouseReleaseEvent if it fires every time.
If yes, then something else is still not 100% like a mouse.

I had some issues with some widgets that look for mouse move and mouse leave events ( focusin/out)
which is not (always) send with a touch. But I dont remember a plain combobox being an issue.

Have you tested with some non Qt app ?
Does it accept the touch fully as a mouse?

Andrey Shmelew

@mrjj
i will answer tomorrow! need to go :(
Thank you!

Andrey Shmelew

@mrjj
Hello and Happy New Year!

I installed VLC media player on my beaglebone, and have been playing with controls (combobox, scrollbars etc...), and all was going well, no bugs with comboboxes, touch screen clicks and releases fine.
I noticed that combobox in VLC player and combobox in QT are differented of each other.

VLC acceps the touch fully as a mouse, i suppose.

mrjj

@Andrey-Shmelew
Hi
Happy new year to you too

Ok it does sound like it is working as it should. Maybe VLC is very touch friendly.

Can we test with one app ( nothing as well used with touch as VLC ) to test ?

Still think its just controller that slips a mouse up sometimes but not sure yet.

Andrey Shmelew

@mrjj said in Simulate left mouse button unclick (release button):

Can we test with one app ( nothing as well used with touch as VLC ) to test ?

yes, sure, i will try evrethyng i can

mrjj

@Andrey-Shmelew
Super
Did you also check with main window that
void MainWindow::mouseReleaseEvent(QMouseEvent* event)
{
qDebug() << ("button Released");
}

is always called?
Make sure only to click on the mainwindow.

Andrey Shmelew

@mrjj said in Simulate left mouse button unclick (release button):

is always called

if only i did not press combobox...

As soon as I clicked combobox, no matter how many times I clicked on the mainwindow, label_7 is always "Only left button"

qDebug() << ("button Released"); is not working in linux app, so i use label_7 as debug out

mrjj

@Andrey-Shmelew
Yes combo is special as it drop down a floating window and use event filer for selection so
it is not canceled correctly, it will then eat all events and nothing else can be clicked.

ehh qDebug() not working in linux ? you mean outside Creator or ?
Dont matter. Label is fine :)

Andrey Shmelew

@mrjj
Hello!

So, the problem is not solved,
should i use events filter?

thanks!

mrjj

@Andrey-Shmelew
well, i would dig a bit deeper into what is going on.
I never seen combo not work like that.
Seems something else than missing events.

But yes, you can most likely work around using event filters but there might surface other stuff
like broken drag and drop or something as its not a bug in combobox ( no other reports) as such so
something else is not as expected with the touch.

I tried at work with touch screen and could not reproduce it so Im a bit lost why
its not just closing its dropdown.

I think it will/might be a mess with eventfilter
but if you only have one combobox you
need to fix it should be ok
but if you use combos all over program i would
go for better solution.

Andrey Shmelew

@mrjj
Unfortunately, i use combos all over program. I want to use comboboxes for configure my device. if you could not reproduce it, maybe it happens because of my touch's non-correct work. If i could make any help for you for help me ...

mrjj

@Andrey-Shmelew

Hmm, I asked another mod here for some input (later) as there is something
funky here. Maybe im overlooking something.
If your touch acts as pure touch or is faulty then other controls should also have issues.

But since we do not have any event trace is very unclear what is happening.
Also as far as I know, the drop down part of the combobox is already using event filter.
So its not sure event filters are a good/easy fix.

I think i would still dig deeper to find real reason. ( look in Qt source)

Alternatively, make my own combo box and control the dropdown with lost focus if possible.
Didnt check the code so not sure how it handles the dropdown.

raven-worx

@Andrey-Shmelew
whats your touch screen model?
Whats your input mode (evdev, tslib, libinput) used?
What is your used Qt platform (X, LinuxFB, EGLFS)?

Just to make sure: you are using QtWidgets right, not QML?

btw. VLC also uses Qt for it's GUI. But i currently don't know which version.
Can you also try to use Qt 5.8 RC if you encounter the same issues?

Also you could log all events like the following. Start the application from the console and you should see the output in stdout.

qApp->installEventFilter( this );
...
bool eventFilter( QObject* watched, QEvent* event )
{
     switch( event->type() )
     {
               case QEvent::MousePressEvent:
               case QEvent::MouseReleaseEvent:
               case QEvent::TouchBegin:
               case QEvent::TouchCancel:
               case QEvent::TouchEnd:
                        qDebug() << int(event->type()) << watched;
              break;
     }

     return BaseClass::eventFilter(watched,event);
}

Andrey Shmelew

@raven-worx
This is my display : http://www.waveshare.com/10.1inch-hdmi-lcd-b-with-case.htm
i dont know inpute mode (maybe this is a reason of a bug)
i also dont know qt platform (maybe Qt Creator 4.1.0
Основан на Qt 5.7.0 (MSVC 2013, 32 бита) is answer), and i built qt everywere with gcc arm none eabi compiler.
I use QtWidgets, not QML, i am sure.
OK I think i can try QT 5.8 RC
Ok i will log all events following your code

here is video demonstrates how combo works https://drive.google.com/file/d/0ByPoVqOCWO2IVERuMkMzTmZsMjA/view

raven-worx

@Andrey-Shmelew
in the video the mouse cursor changes it's shape (to Qt::IBeamCursor), from then on your widgets do not react anymore.
You can also log the focus changes by connecting to QApplication::focusChanged() signal. It would be interesting what's the focus widget is in that case.

Maybe you use QWidget::grabMouse() in this widget?

Can you also please set QT_DEBUG_PLUGINS=1 environment variable and post the output from the console. Maybe before/after you try the other debug output.
This shows what plugins are being loaded.