signals and slots with little c++ knowledge

[wenn32]

hello, i am new to QT and i am trying to learn QT and its features.But as a C guy i am facing a bit difficult in understanding signals and slots except this feature the Docs provided by QT is more than enough for me

i use code blocks along with QT libraries to do the magic with C and it works great!.

i need help from you guys.can you please tell me how to create a new slots and how to manipulate data with it.i have some very small basic knowledge on c++ so i can understand little bit.

for example is this correct?

int main(int argc, char* argv[])
{
    QApplication app(argc, argv);
    QPushButton clickme("ClickeME");
    clickme.resize(75, 30);
    clickme.setFont(QFont("Times", 18, QFont::Bold));
    QObject::connect(&clickme, SIGNAL(clicked()), &app, SLOT(updatenewvalues()));
    clickme.show();
    return app.exec();
}
 
void updatenewvalues()
{
 /* some code here */
}

int main(int argc, char* argv[])
{
    QApplication app(argc, argv);
    QPushButton clickme("ClickeME");
    clickme.resize(75, 30);
    clickme.setFont(QFont("Times", 18, QFont::Bold));
    QObject::connect(&clickme, SIGNAL(clicked()), &app, SLOT(updatenewvalues()));
    clickme.show();
    return app.exec();
}

void updatenewvalues()
{
 /* some code here */
}

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what i want this program to do is initially the value in clickme is "clickme" no when i press clickme i want the value of "clickme" to change to "dontclickme"

i have read the Docs from here
http://doc.trolltech.com/4.7/signalsandslots.html
but no help!

[Timoteo]

Here's your program done the c++ way:

#ifndef PUSHBUTTON_H
#define PUSHBUTTON_H
#include <QPushButton>
#include <QString>
/*Here, we subclass QPushButton so that we can define a new slot:
  updatenewvalues().
  It is worth noting that we could have subclassed QApplication
  to add the new slot also.  Qt is awesome like that!
  For brevity's sake, the class is defined inline in a header.  This is
  generally a bad idea!*/
 
class PushButton: public QPushButton
{
    Q_OBJECT
public:
    PushButton(QWidget* parent = 0): QPushButton(parent){}
    PushButton(const QString& text, QWidget* parent = 0) : QPushButton(text, parent){}
public slots:
    void updatenewvalues()
    {
        if(this->text() == "Don't click me!")
        {
            setText("Click me!");
            return;
        }
        setText("Don't click me!");
    }
};
#endif // PUSHBUTTON_H

#ifndef PUSHBUTTON_H
#define PUSHBUTTON_H
#include <QPushButton>
#include <QString>
/*Here, we subclass QPushButton so that we can define a new slot:
  updatenewvalues().
  It is worth noting that we could have subclassed QApplication
  to add the new slot also.  Qt is awesome like that!
  For brevity's sake, the class is defined inline in a header.  This is
  generally a bad idea!*/
 
class PushButton: public QPushButton
{
    Q_OBJECT
public:
    PushButton(QWidget* parent = 0): QPushButton(parent){}
    PushButton(const QString& text, QWidget* parent = 0) : QPushButton(text, parent){}
public slots:
    void updatenewvalues()
    {
        if(this->text() == "Don't click me!")
        {
            setText("Click me!");
            return;
        }
        setText("Don't click me!");
    }
};
#endif // PUSHBUTTON_H

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Then:

/*now we employ our new class*/
int main(int argc, char* argv[])
{
    QApplication app(argc, argv);
    PushButton clickme("Click me!");
    clickme.resize(200, 30);
    clickme.setFont(QFont("Times", 18, QFont::Bold));
    QObject::connect(&clickme, SIGNAL(clicked()), &clickme, SLOT(updatenewvalues()));
    clickme.show();
    return app.exec();
}

/*now we employ our new class*/
int main(int argc, char* argv[])
{
    QApplication app(argc, argv);
    PushButton clickme("Click me!");
    clickme.resize(200, 30);
    clickme.setFont(QFont("Times", 18, QFont::Bold));
    QObject::connect(&clickme, SIGNAL(clicked()), &clickme, SLOT(updatenewvalues()));
    clickme.show();
    return app.exec();
}

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I suggest some reading to help with your learning c++. You can find several good books on Qt with c++ at Amazon.com.