Qt textfinder tutorial issue

Cannabis2011

Hello, im a little (Or a big) noob to this -QT- Qt framework, and i trying to understand how it works. I was trying the Textfinder tutorial in -QT- Qt Creator, but without any succes. I have done all the tasks, but in the end, Im getting thís error:

@
D:\QtSDK\Examples\TextFinder-build-desktop-Qt_4_7_4_for_Desktop_-_MinGW_4_4__Qt_SDK__Debug..\TextFinder\textfinder.cpp:19: error: no 'void TextFinder::on_findButton_clicked()' member function declared in class 'TextFinder'
@

My textfinder.cpp is looking like this:

@
#include "textfinder.h"
#include "ui_textfinder.h"
#include <QtCore/QFile>
#include <QtCore/QTextStream>

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

TextFinder::~TextFinder()
{
delete ui;
}

void TextFinder::on_findButton_clicked()
{
QString searchString = ui->lineEdit->text();
ui->textEdit->find(searchString, QTextDocument::FindWholeWords);
QMetaObject::connectSlotsByName(TextFinder);
}

void TextFinder::loadTextFile()
{
QFile inputFile(":/input.txt");
inputFile.open(QIODevice::ReadOnly);

 QTextStream in(&inputFile&#41;;
 QString line = in.readAll();
 inputFile.close();

 ui->textEdit->setPlainText(line);
 QTextCursor cursor = ui->textEdit->textCursor();
 cursor.movePosition(QTextCursor::Start, QTextCursor::MoveAnchor, 1);

}
@

Can someone explain what i had done wrong, and i apoligize for my bad english.

[EDIT: code formatting, please wrap in @-tags, Volker]

goetz

You most probably forgot to add on_findButton_clicked() as a public slot in your class header file textfinder.h

It should look something like this:

@
class TextFinder : public QWidget
{

Q_OBJECT

public:
// your constructors etc. here

protected slots:
void on_findButton_clicked();

// ... other stuff ...
};
@

Cannabis2011

This is my header file:

@
#ifndef TEXTFINDER_H
#define TEXTFINDER_H

#include <QWidget>

namespace Ui {
class TextFinder;
}

class TextFinder : public QWidget
{
Q_OBJECT

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

private slots:

void on_FindButton_clicked();

private:
Ui::TextFinder *ui;
void loadTextFile();
};

#endif // TEXTFINDER_H
@

mlong

Again, please put @ tags around your code samples.

(Above post edited to make @-tag correction.)

goetz

on_findButton_clicked != on_FindButton_clicked

(f vs. F in find vs. Find)

Cannabis2011

Sorry, im all new to this. But it helped, thanks a lot.

goetz

You're welcome. Please always keep in mind that C++ (and C) are case sensitive languages, so a variable x is not the same a variable X. Also this affects the autoconnection, so you should double check the exact spelling of your widget in the UI (upper or lower case F).

BTW: If you use Qt Creator as your IDE, just go to the header file, put the cursor on a method name and press alt-return, this will add a stub implementation in your .cpp file with all the spelling and upper/lower case done right :)

Byro

Hi,
I'm just starting too. At this point in time it seems the following will work

@QMetaObject::connectSlotsByName(this);@

The most reasonable place to place it is in the TextFinder constructor, so it looks like this:

@TextFinder::TextFinder(QWidget *parent) :
QWidget(parent),
ui(new Ui::TextFinder)
{
ui->setupUi(this);
loadTextFile();
QMetaObject::connectSlotsByName(this);
}@

I am not sure why would you want it in a clicked event and no one corrected you. :)

Using version
Qt Creator 2.4.1
Based on Qt 4.8.0 (64 bit)
Built on Mar 21 2012 at 22:53:22

lypo

[quote author="Byro" date="1343928612"]
The most reasonable place to place it is in the TextFinder constructor, so it looks like this:
@TextFinder::TextFinder(QWidget *parent) :
QWidget(parent),
ui(new Ui::TextFinder)
{
ui->setupUi(this);
loadTextFile();
QMetaObject::connectSlotsByName(this);
}@[/quote]

Yeah, thanks Byro! It works. In the Tutorial is not written where to place the QMetaObject::
Also they want the className "TextFinder" - this dosn't work.

This is my first work with Qt - I looked for the mistake half the night. :-(
Now I'm HAPPY!

@Volker: Thanks for your advice! Sounds very useful. :-)

Sorry, I hope you'll understand my bad english - had been a bad teacher in school - 43 years ago. :-)