Can't Compile connect method

[theroark]

I am new to Qt. I am trying to learn to make Notepad from tutorial available online by Qt.
The following method throws an undefined reference to 'Notepad::newDocument()'
error:

connect(ui->actionNew,&QAction::triggered,this,&Notepad::newDocument);

Some tips on this please...

[Christian Ehrlicher]

So where did you implement the function Notepad::newDocument() ?

[mrjj]

Hi and welcome to the forums.

If this example
https://doc.qt.io/qt-5/qtwidgets-tutorials-notepad-example.html
Then first you add the slot

class Notepad : public QMainWindow
{
    Q_OBJECT

public:
    explicit Notepad(QWidget *parent = 0);
    ~Notepad();

private slots:
    void newDocument(); <<<
...

then later they show the implementation. Which goes in the cpp file.

void Notepad::newDocument()
{
    currentFile.clear();
    ui->textEdit->setText(QString());
}

[theroark]

@mrjj
Thanks a lot...
I tried that as well it doesn't work. :(

[SGaist]

Hi,

You have to give more details. "Doesn't work" goes from missing a semi-colon to asteroid hitting the earth Tunguska style.

[theroark]

@SGaist I understand. below is the in detail description of the problem.

I first declared the signal element shown below with actionNew:

Then I declared a slot like below:

After that I connected them and below show are the compiled results :

[SGaist]

You have to implement the slot even if empty to get started.

[JKSH]

@theroark said in Can't Compile connect method:

Then I declared a slot like below:

A declaration is not enough. You must also give it a function body.

• See https://docs.microsoft.com/en-us/cpp/cpp/functions-cpp?view=vs-2019 for an explanation.
• See @mrjj's post above for a solution.

[theroark]

Hey all, @JKSH @SGaist @mrjj,

Thanks, It worked!!!!