Problem on SIGNALS and SLOTS

rezaMSLM

I designed a GUI to upload and download files from my FTP server
when i click on upload button, uploads my file on the server successfully.
in order to see upload progress added a progress bar to the GUI.
I know that when uploading and downloading dataTransferProgress() signal is emited.
I tried to connect this signal to my progress bar:

connect(ftp, SIGNAL(dataTransferProgress(qint64, qint64)), this ,SLOT(ui->progressBar_Upload));

I receive no error but it doesnt work!

J.Hilk

@rezaMSLM said in Problem on SIGNALS and SLOTS:

connect(ftp, SIGNAL(dataTransferProgress(qint64, qint64)), this ,SLOT(ui->progressBar_Upload));

there's defenitly an error, but the old Signal/Slot syntax does not show it during compile time.

try the following:

 connect(ftp, QFTP::dataTransferProgress, ui->progressBar_Upload ,[=](qint64 current, qint64 max){
     ui->progressBar_Upload->setValue(current);
     ui->progressBar_Upload->setMaximum(max);
});

this should work.
If you're bound to qt4 or something, you'll need a slot in your Class(Mainwindow?)

connect(ftp, SIGNAL(dataTransferProgress(qint64, qint64)), this ,SLOT(newProgressValues(qint64, qint64));

void Mainwindow::newProgressValues(qint64 current, qint64 max){
     ui->progressBar_Upload->setValue(current);
     ui->progressBar_Upload->setMaximum(max);
}

sierdzio

check if connection worked (connect() returns a bool)
use new connection syntax - it will give you compilation errors when something is wrong in connection statement
you are not specifying any actual slot in your SLOT() macro call, so I'm 99% sure it fails there. You should rather do it like:

connect(ftp, SIGNAL(dataTransferProgress(qint64, qint64)), ui->progressBar_Upload ,SLOT(nameOfYourSlot(qint64, qint64)));

sierdzio

Oh, what timing :)

J.Hilk

@sierdzio for the "easy questions" people tend to answer within the same minute. I had it once, where 5 people answred within 1 minute x)

sierdzio

Haha, nice :-)

JonB

There are easier questions than this one... :)

JKSH

@J.Hilk said in Problem on SIGNALS and SLOTS:

@sierdzio for the "easy questions" people tend to answer within the same minute. I had it once, where 5 people answred within 1 minute x)

I'm starting to think we should have Sticky threads for those... :P

J.Hilk

@JKSH You mean, like an FAQ->Readonly sub-categorie ? Sounds like a plan :)

rezaMSLM

when using QFtp::put() command I want to be noticed whether the command successfully finished or not; so I want to use "void QFtp::commandFinished ( int id, bool error )" SIGNAL.
from Qt help:
"This signal is emitted when processing the command identified by id has finished"
now my question is that what is QFtp::put() command id?
in other words:
when commandfinished() signal is emitted how I understand which command is finished?

jsulm

@rezaMSLM said in Problem on SIGNALS and SLOTS:

now my question is that what is QFtp::put() command id?

Please read the documentation: http://doc.qt.io/archives/qt-4.8/qftp.html#put-2
The id is what QFtp::put() returns...