Click through windows

Vunnm

Hi,

How do I create a transparent window with mouse events going through the window? Actually I try to set transparency with this in the constructor:

setAttribute(Qt::WA_TranslucentBackground, true);

But it only works on linux, under Windows I get a black background and I still don't know how to make mouse click going through my window.
I hope someone will know how to fix it :)

SGaist

Hi and welcome to devnet,

Looks like you want: widget->setAttribute(Qt::WA_TransparentForMouseEvents).

Vunnm

@SGaist I already try it:

here is my code:

#include "transparentwindow.h"

TransparentWindow::TransparentWindow() : QWidget()
{
    setFixedSize(300, 150);

    m_b= new QPushButton("Ok", this);
    //setWindowFlag(Qt::X11BypassWindowManagerHint);
    setAttribute(Qt::WA_NoSystemBackground, true);
    setAttribute(Qt::WA_TranslucentBackground, true);
    setAttribute(Qt::WA_TransparentForMouseEvents);
}

header of the file:

#ifndef TRANSPARENTWINDOW_H
#define TRANSPARENTWINDOW_H

#include <QObject>
#include <QWidget>
#include <QPushButton>

class TransparentWindow : public QWidget
{
public:
    TransparentWindow();

protected:
    QPushButton *m_b;
};

#endif // TRANSPARENTWINDOW_H

and my main.cpp:

#include <iostream>
#include <QApplication>
#include <transparentwindow.h>

int main(int argc, char**argv)
{
QApplication app(argc, argv);
TransparentWindow f;
f.show();

return app.exec();

}

but here is the result:

mrjj

Hi
Being drawn transparently or have mouse event passthrough is not the same.
Anyway, i used this to have a 100% invisible window and clicks went through it.
(win 10, not tried on linux)

class Overlay : public QWidget {
  Q_OBJECT
public:
  explicit Overlay ( QWidget* parent = 0 ) :
    QWidget ( parent ) {
    setPalette ( Qt::transparent );
    setAttribute ( Qt::WA_TransparentForMouseEvents );
  }
protected:
  void paintEvent ( QPaintEvent* event ) {} // draw nothing ( i did draw some stuff) not 100% sure its needed.
};

Vunnm

@mrjj I simply copy/paste your code but I still get the same result: a black window and the click don't go through the window (I try it on both Windows and linux).

mrjj

@Vunnm

Works here. (win 10)
You can try my sample
https://www.dropbox.com/s/v74riecj5zq1t3t/trans.zip?dl=0

Vunnm

Well your project don't work for my, perhaps because I am using a 64 bits Windows 7 on virtual machine and compiling my project in 32 bits. But anyway I find a solution on another forum, here.

here the constructor of my transparent and click-through window:

MyWindows::MyWindows() : QWidget()
{
    //setWindowFlag(Qt::X11BypassWindowManagerHint); 
    setAttribute(Qt::WA_TranslucentBackground, true);
    setAttribute(Qt::WA_TransparentForMouseEvents);

    setWindowFlags(Qt::FramelessWindowHint);
    setWindowFlags(Qt::FramelessWindowHint | Qt::WindowStaysOnTopHint); //we can add Qt::Tool
    //setFixedSize(300,300);

}

so thanks everyone for your help!