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RHMK
25th December 2010, 12:07
Hi
I 'm a beginner in QT.
My class's slots in my code do not work!!


test.cpp:


#include <QHBoxLayout>
#include <QVBoxLayout>
#include "test.h"

FindDialog::FindDialog( QWidget *parent): QDialog(parent)
{
label = new QLabel(tr("Find &what:"));
lineEdit = new QLineEdit;
label->setBuddy(lineEdit);

caseCheckBox = new QCheckBox(tr("Mach &case"));
backwardCheckBox = new QCheckBox(tr("Search &backward"));

findButton = new QPushButton(tr("&Find"));
findButton->setDefault(true);
findButton->setEnabled(false);

closeButton = new QPushButton(tr("Close"));

connect(lineEdit,SIGNAL(textChanged(const QString &)),this,SLOT(this->enableFindButton(const QString &)));
connect(findButton , SIGNAL(clicked()),this,SLOT(this->findClicked()));
connect(closeButton,SIGNAL(clicked()),this,SLOT(cl ose()));

QHBoxLayout *topLeftLayout = new QHBoxLayout;
topLeftLayout->addWidget(label);
topLeftLayout->addWidget(lineEdit);

QVBoxLayout *leftLayout = new QVBoxLayout;
leftLayout->addLayout(topLeftLayout);
leftLayout->addWidget(caseCheckBox);
leftLayout->addWidget(backwardCheckBox);

QVBoxLayout *rightLayout = new QVBoxLayout;
rightLayout->addWidget(findButton);
rightLayout->addWidget(closeButton);
rightLayout->addStretch();

QHBoxLayout *mainLayout = new QHBoxLayout;
mainLayout->addLayout(leftLayout);
mainLayout->addLayout(rightLayout);
setLayout(mainLayout);

setWindowTitle(tr("Search"));
setFixedHeight(sizeHint().height());
}

void FindDialog::findClicked()
{
QString text = lineEdit->text();
Qt::CaseSensitivity cs = caseCheckBox->isChecked() ? Qt::CaseSensitive : Qt::CaseInsensitive;
if (backwardCheckBox->isChecked()) {
emit findPrevious(text,cs);
} else {
emit findNext(text,cs);
}
}

void FindDialog::enableFindButton(const QString &text)
{
findButton->setEnabled(!text.isEmpty());
}


test.h:


#ifndef FINDDIALOG_H
#define FINDDIALOG_H

#include <QtGui>
#include <QDialog>

#include <QCheckBox>
#include <QLabel>
#include <QLineEdit>
#include <QPushButton>

class FindDialog : public QDialog
{
Q_OBJECT

public :
FindDialog(QWidget *parent = 0);

signals:
void findNext(const QString &str , Qt::CaseSensitivity cs);
void findPrevious(const QString &str , Qt::CaseSensitivity cs);

private:
QLabel *label;
QLineEdit *lineEdit;
QCheckBox *caseCheckBox;
QCheckBox *backwardCheckBox;
QPushButton *findButton;
QPushButton *closeButton;

private slots:
void findClicked();
void enableFindButton(const QString &text);

};
#endif



main.cpp:


#include <QApplication>
#include "test.h"

int main(int argc,char *argv[])
{
QApplication app(argc,argv);
FindDialog *fd = new FindDialog;
fd->show();
return app.exec();
}


Please help me about this.
Thanks

Zlatomir
25th December 2010, 12:33
Remove the extra 'this' pointer from the connect statements:


connect(lineEdit,SIGNAL(textChanged(const QString &)),this, SLOT(enableFindButton(const QString &)));
connect(findButton , SIGNAL(clicked()),this, SLOT(findClicked()));

LE:Next time, please use the code tags (the button #) to post code on the forum, it's goins to be easier to read, qtclass it's not for code posting.

BalaQT
25th December 2010, 12:35
hi,
pls post ur code with [code] tag.
where u r strucked?
Bala

RHMK
26th December 2010, 09:36
Thanks
I checked that on my pc not work then check it on another pc and worked !!!

thanks again for your replay ;)

Zlatomir
26th December 2010, 12:11
It should work on your pc too, use the Clean All (from Build menu), then Rebuild.

RHMK
26th December 2010, 13:45
Thanks :)
I clean project and make again but not work on my pc anyway.