How to transffer QImage or QPixmap from one window to another using signals and slots

swansorter

@KroMignon yes i am using right class instance . i have pasted my code

KroMignon

@swansorter said in How to transffer QImage or QPixmap from one window to another using signals and slots:

yes i am using right class instance . i have pasted my code

Your code seem at little bit confusing to me.
Why do you use old connect syntax here:

connect(obj,SIGNAL(Mouse_Left(QString)),this,SLOT(Mouse_Left(QString)));

and not new syntax?

connect(obj,&my_qlabel::Mouse_Left,this, &MainWindow::Mouse_Left);

Where did you add obj to the layout?

jsulm

@swansorter And please be so kind and format your code properly to make it easier for others to read it...

swansorter

@JonB i resolved issue .by changing this
connect(obj,SIGNAL(Mouse_Left(QString)),this,SLOT(Mouse_Left(QString)));
to
connect(ui.label,SIGNAL(Mouse_Left(QString)),this,SLOT(Mouse_Left(QString)));
}

JonB

@swansorter
This is hardly the minimal example I asked for....

Do not use SIGNAL/SLOT macros if you are to have any chance of debugging what is going on. You do not even check your connect()s return result. Use the new syntax only.

You declare Mouse_Left as a signal, yet you provide your own implementation of a method with that name. I don't know that you can do that.

I'm quite mixed up about what are signals and what are slots in main window vs the label.

If you want me to look further: Name your slots differently from your signals, else it's too confusing. Reduce to a minimal example. And enclose blocks of code with the form posts' Code tag.

UPDATE
Crossed with your latest post. Advice: get rid of SIGNAL/SLOT in all your code, only use new style, to help both you and others.

swansorter

@jsulm sorry ill do that

swansorter

@JonB do you have the link for the new style SIGNAL/SLOT Diclaration

jsulm

@swansorter said in How to transffer QImage or QPixmap from one window to another using signals and slots:

do you have the link for the new style SIGNAL/SLOT Diclaration

Easy to find with Google: https://doc.qt.io/qt-5/signalsandslots.html

JonB

@swansorter
Additionally to @jsulm, you originally had it with your

connect(test_label,&my_qlabel::sendImage,this,&MainWindow::onGetImage);

You then changed over to SIGNAL/SLOT, for no discernible reason, which may be a clue as to why it went wrong....