Form load function

[t0msk]

i created new form in Qt and i would like to ask you where is form load function, where i can put my code.

And another problems are that file_exists doesn't work and i dont know why (i would like to use C native functions), and my Messagebox show before form load why? I would like to load while form and then show my Messagebox. And the last thing is that this->close(); at if statement doesn't work.

This is my code:

@#include "nacitanie_okno.h"
#include "ui_nacitanie_okno.h"
#include "funkcie.h"
#include <iostream>

const char *subory[] = { "test.txt" } ;

nacitanie_okno::nacitanie_okno(QWidget *parent) :
QDialog(parent),
ui(new Ui::nacitanie_okno)
{
ui->setupUi(this);

int i;
int pocet = 1;

int percent = 20 / pocet;
for(i = 0; i < pocet ; i++){

    if(file_exists(subory[i])){
        ui->progressBar->setValue(ui->progressBar->value() + percent);
    } else {
        MessageBox("Hi","teeest"); // my own function for messagebox
        this->close();
    }
}

}

nacitanie_okno::~nacitanie_okno()
{
delete ui;
}@

and in funkcie.h is this:

@bool file_exists(const char * subor)
{
if (FILE * sub = fopen(subor, "r"))
{
fclose(sub);
return true;
}
return false;
}@

thank you

[t0msk]

[quote author="SGaist" date="1416439024"]You can't but C++ code anywhere in a file like that.

Also, Afterload doesn't belong to MainWindow.

Are you a C++ beginner ?[/quote]

At C++ yes, but i have experiences with C and C#. So how does it work? Where i have to put it? :)

Thank you

[SGaist]

in e.g. main.cpp

You should take the time to go through Qt's tutorial and read some of the examples/demos provided with Qt's sources.

[t0msk]

Okey i found solution.

I just add to mainwindow.h

@public:
void load();@

And in mainwindow.cpp

@void MainWindow::load() {
QThread::msleep(500);
QMessageBox msgBox;
msgBox.setText("The document has been modified.");
msgBox.exec();
}@

And then i call it from main.cpp

@ MainWindow w;
w.show();
w.load();@

This works but it amazes me that such an important function is not implemented in default "Slots" (Go to slot) in Qt Creator :)

Thank you

[SGaist]

Important in your you ;)

There are several possibilities to achieve that and without knowing what exactly you'd like to do after the widget is shown, it's not easy to help you.

[t0msk]

[quote author="SGaist" date="1416698455"]Important in your you ;)

There are several possibilities to achieve that and without knowing what exactly you'd like to do after the widget is shown, it's not easy to help you.[/quote]
I have one more question how can i call function after all items in widgets are constructed? (By items i mean for example, buttons, progress bar etc). Because when i write:

@void MainWindow::load() {
QThread::sleep(1);
// my func
}@

then i have to wait 1 second + execution time of my func to load all items in widget. I would like to construct all items and then call my func.

Can you help me please?

Thank you very much! :)

[SGaist]

QTimer::singleShot is your friend

[t0msk]

[quote author="SGaist" date="1416876558"]QTimer::singleShot is your friend[/quote]

Do you mean this?

mainwindow.cpp

@#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QMessageBox>
#include <QTimer>
#include <QThread>

void MainWindow::do_it(){

QMessageBox msgBox;
msgBox.setText("My func.");
msgBox.exec();

}

void MainWindow::Afterload(){
QTimer::singleShot(500, this, SLOT(do_it()));
}

MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
}

MainWindow::~MainWindow()
{
delete ui;
}@

mainwindow.h

@#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
Q_OBJECT

private slots:
void do_it();

public:
explicit MainWindow(QWidget *parent = 0);
~MainWindow();
void Afterload();

private:
Ui::MainWindow *ui;
};

#endif // MAINWINDOW_H@

This works, but i am wondering if is this correct :)

[SGaist]

Rather:

@MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
QTimer::singleShot(0, this, SLOT(do_it()));
}@