[Solved] Substitute of QWSMouseHandler class in QT5.x

Sidii

Dear all,
i want to port my QT4.8 application to QT5.3 and one class is derived from QWSMouseHandler, any idea how to implement the same functionality in QT5?

Please let me know.
Thanks

SGaist

Hi,

I think it will depend on what plugin you use now. Have a look at the input folder in qtbase/src/platformsupport.

Hope it helps

Sidii

Thanks SGaist,

I checked inside:

/qtbase/src/platformsupport/input

There are following folders:

evdevkeyboard
evdevmouse
evdevtablet
evdevtouch

I read somewhere that evdev* works for eglfs platform.

Can i use it for LinuxFB also?
I am using QT_QPA_PLATFORM=linuxfb

Will evdevmouse will work for linux framebuffer also?

Kindly clarify this doubt also. Thanks a lot

SGaist

AFAIK, yes, linuxfb like eglfs has nothing to do with input devices

Sidii

Dear SGaist, thanks a lot for clarifying my doubt.

Now suppose my QT application which contains One main window and inside that only one button is present. This app is kept inside:

@/home/Sid/./ButtonApp@

Now where should i keep the evdevmouse plugin?

Should i place it under:

@/home/Sid/plugins/libqevdevmouseplugin.so@

OR

@/home/Sid/plugins/generic/libqevdevmouseplugin.so@

I am also setting the environment variable like this:

@export QT_QPA_GENERIC_PLUGINS=evdevmouse:/dev/ttyS1@

I also modified the main.cpp file which is kept inside:

qtbase/src/plugins/generic/evdevmouse

by adding a qDebug statement:

@
QObject* QEvdevMousePlugin::create(const QString &key,
const QString &specification)
{
qDebug()<<"QEvdevMousePlugin::create";
if (!key.compare(QLatin1String("EvdevMouse"), Qt::CaseInsensitive))
return new QEvdevMouseManager(key, specification);
return 0;
}

@

But still when i run my QT application (./ButtonApp) i did not get any qDebug output.

Kindly point out what i am doing wrong :(

Thanks

SGaist

Since you are trying to play with a Qt plugin, put it in your target Qt's installation plugin path

Sidii

Dear SGaist,
Thanks for your reply.
Now i have set the plugins directory by doing:
@export QT_PLUGIN_PATH=/home/Sid/plugins/generic@

and QT's mouse plugin: libqevdevmouseplugin.so
is located in the same directory, but still no qDebug lines are printed. I think control is not reaching to the evdevmouse plugin :(

SGaist

set QT_DEBUG_PLUGINS=1 to see what happens with your plugins

Sidii

Dear SGaist,
Thanks for highlighting my mistake actually i did this:

@export QT_DEBUG_PLUGIN=1@

instead of this:

@export QT_DEBUG_PLUGINS=1@

So i made PLUGIN to PLUGINS now i am getting lot of thins on screen. Let me check in detail. I will get back to you.

Thanks a lot :)

Sidii

Dear SGaist,

I gave following command to run my application:

@./buttonApp -plugin evdevmouse:/dev/ttyS1@

And i got following output:

@
QFactoryLoader::QFactoryLoader() checking directory path "/home/Sid/platforms" ...
QFactoryLoader::QFactoryLoader() looking at "/home/Sid/platforms/libqlinuxfb.so"
Found metadata in lib /home/Sid/platforms/libqlinuxfb.so, metadata=
{
"IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.2",
"MetaData": {
"Keys": [
"linuxfb"
]
},
"className": "QLinuxFbIntegrationPlugin",
"debug": false,
"version": 328193
}

Got keys from plugin meta data ("linuxfb")
QFactoryLoader::QFactoryLoader() looking at "/home/Sid/platforms/libqminimal.so"
Found metadata in lib /home/Sid/platforms/libqminimal.so, metadata=
{
"IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.2",
"MetaData": {
"Keys": [
"minimal"
]
},
"className": "QMinimalIntegrationPlugin",
"debug": false,
"version": 328193
}

Got keys from plugin meta data ("minimal")
QFactoryLoader::QFactoryLoader() looking at "/home/Sid/platforms/libqoffscreen.so"
Found metadata in lib /home/Sid/platforms/libqoffscreen.so, metadata=
{
"IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.2",
"MetaData": {
"Keys": [
"offscreen"
]
},
"className": "QOffscreenIntegrationPlugin",
"debug": false,
"version": 328193
}

Got keys from plugin meta data ("offscreen")
QFactoryLoader::QFactoryLoader() checking directory path "/home/Sid/plugins/generic/platforms" ...
loaded library "/home/Sid/platforms/libqlinuxfb.so"

QFactoryLoader::QFactoryLoader() checking directory path "/home/Sid/generic" ...
QFactoryLoader::QFactoryLoader() checking directory path "/home/Sid/plugins/generic/generic" ...
QFactoryLoader::QFactoryLoader() checking directory path "/home/Sid/styles" ...
QFactoryLoader::QFactoryLoader() checking directory path "/home/Sid/plugins/generic/styles" ...

@

Nothing is shown related to evdevmouse.
Required (.so) file is kept here:
@/home/Sid/plugins/generic/libqevdevmouseplugin.so@

Can you please guide me why it is not loading :(
What extra i need to do or some other setting i need to do.

Kindly help

Thanks

Sidii

Also i have removed -DQT_NO_DEBUG
from the makefile of evdevmouse. So now it is debug enabled.
But still i no output i am getting from qDebug statements.

It is not getting loaded :(

Sidii

Dear SGaist,
I am able to load the plugin. There was problem in the path. Thanks a lot :) for pointing to the QT_DEBUG_PLUGINS=1

I am getting qDebugs getting printed. But again i have one more doubt:

What is the difference between:

/qtbase/src/plugins/generic/evdevmouse

AND

/qtbase/src/platformsupport/input/evdevmouse

Actually to get the touch coordinates i want to add debug points to the code located in :

/qtbase/src/platformsupport/input/evdevmouse

But to my surprise, both the above locations are not interlinked.

Do i need to merge the code?

SGaist

/qtbase/src/plugins/generic/evdevmouse is only the plugin stuff

/qtbase/src/platformsupport/input/evdevmouse is the actual code

AFAIK, the input code is builtin, so if you play with it, you have to deploy the libraries

Sidii

Dear SGaist, Thanks for your reply.

I am now using serial port to read the touch screen values. Actually our touch screen is working as a mouse. I am able to get the exact touch coordinates. But now what should i do with those coordinates?
I saw that in my old QT4x code one slot was called after getting the coordinates:

@QWSMouseHandler::mouseChanged(position, state, wheel);@

But now i want to port it to the QT 5. Can u please tell me how to proceed. i have seached evdevmouse plugin but there is no such slot.

My question is that i am able to get the x and y. but how should i pass to the QT so that button can be seen as pressed. Kindly guide me.

Thanks

Sidii

Dear SGaist, i am able to detect the touch by just directly passing the touch coordinates to:
@
QWindowSystemInterface::handleMouseEvent(0, position, position, Qt::LeftButton);
@

But i dont know is this a correct way or not. Also in the header file of QWindowSystemInterface some warning is given:

@
//
// W A R N I N G
// -------------
//
// This file is part of the QPA API and is not meant to be used
// in applications. Usage of this API may make your code
// source and binary incompatible with future versions of Qt.
//

@

Kindly guide me to the correct way.

Thanks :)

SGaist

How are you doing it ?

Sidii

Dear SGaist,

Actually since tslib was not working with serial port touch screen, i wrote one program to get open the serial port and then get the coordinates. Once i get the coordinates, i immediately emit one custom signal(defined by me) and then i call my slot. Inside that slot i have written:

@
QWindowSystemInterface::handleMouseEvent(0, position, position, Qt::LeftButton);
@

So i am able to see the button getting pressed. So i am able to get the touch event. But i am not sure whether this approach is correct or not.

Kindly give your inputs.

Thanks

SGaist

AFAIK there's nothing wrong with that. However, you should create a new generic plugin (you can get some ideas from the tslib one) so you have a reusable component

Sidii

Ok thanks a lot for your guidance. At my end also finally touch screen is working and push buttons are taking the events. Marking the thread as [solved]
:)
Cheers

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[Solved] Substitute of QWSMouseHandler class in QT5.x