[solved]Combining two classes
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Hi,
First of all, I am a beginner in the QT word so sorry if what I wrote is bad.
I would like to create a directory at the beginning of the application. The directory name can varydepending on the situation.
Then I would like to save future files created in a class named fenetre into this directory.
For that:
I create a Class named CreateDirectory , Its constructor creates the directory that will be usedlater and a parameter of this class (QString repertoire) contains the directory name.
I create a class named fenetre and declare 'friend class CreateDirectory;' in its header.I create an objet of the class CreateDirectory named rep in the main.cpp And create a class-fenetre
objet with rep as an argument .
Please find below what I have done so far.
Clicking the button 'next' has no effect.Could you help me out with this problem.
Thank you in advance.@
//main.cpp
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
CreateDirectory *rep= new CreateDirectory;
rep->show();fenetre h(rep); h.show(); return a.exec();}
@@
//CreateDirectory.cpp
CreateDirectory::CreateDirectory(){
int n=1;
QDir lDir;
QString dossier="repertoire";while (true){
dossier = "repertoire"+ qApp->tr("-%1").arg(n);
if ( !lDir.exists ( dossier ))
{
lDir.mkdir(dossier);
break;
}
else
n += 1;
}
//-----------------------repertoire=dossier+"\";
}
@@
fenetre::fenetre(CreateDirectory *rep){DirectoryDeTravail=rep.repertoire; QPushButton *quitter= new QPushButton("Quitter", this); connect(quitter,SIGNAL(clicked()),qApp,SLOT(quit())); QPushButton *next= new QPushButton("Next", this); connect(next,SIGNAL(clicked( CreateDirectory,QLineEdit)),this,SLOT(monslot(CreateDirectory,QLineEdit)));
line= new QLineEdit(this); // a number}
@@
void fenetre::monslot(CreateDirectory *rep, QlineEdit * line)
{
this->hide();
QFile output(QString("%1/nom%2.txt").arg(DirectoryDeTravail).arg(line->text()));fenetre h(rep);
h->show();
}
@ -
Hi, welcome to Qt :) (by the way, the name is "Qt". "QT" is QuickTime)
Your main problem is here:
[quote]
@
QPushButton *next= new QPushButton("Next", this);
connect(next,SIGNAL(clicked( CreateDirectory,QLineEdit)),this,SLOT(monslot(CreateDirectory,QLineEdit)));
@
[/quote]Signals are functions, so you must follow the function prototype.The function prototype for that signal is "void QPushButton::clicked(bool checked = false);":http://qt-project.org/doc/qt-5.0/qtwidgets/qabstractbutton.html#clicked -- it can only take a boolean argument, or no arguments.
So, you cannot write SIGNAL (clicked(CreateDirectory, QLineEdit)) -- you can only write SIGNAL (clicked(bool)) or SIGNAL (clicked()).
You can store the CreateDirectory pointer in your fenetre object, and make fenetre::monslot() take no arguments:
@
fenetre::fenetre(CreateDirectory *rep) {
this->rep = rep;
this->line = new QLineEdit(this);
...
connect(next, SIGNAL(clicked()), this, SLOT(monslot()));
}void fenetre::monslot()
{
this->hide();
QFile output(QString("%1/nom%2.txt").arg(DirectoryDeTravail).arg(this->line->text()));
...
}
@======================
There are also a few other problems:[quote]
@
repertoire=dossier+"\";
@
[/quote]Qt uses '/' for file and directory paths, even in Windows. For example, you should write "C:/MyFolder/MySubfolder/"[quote]
@
void fenetre::monslot(CreateDirectory *rep, QlineEdit * line)
{
this->hide();... fenetre h(rep); h->show();}
@
[/quote]Is the new fenetre created on the heap or the stack?If you use the stack (fenetre h(rep)), it will be destroyed when monslot() returns. If you use the heap (fenetre *h = new fenetre(rep)), the first fenetre still exists, and you have a memory leak.
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Hi,
You're connect statement won't work because QPushButton doesn't have a signal called clicked(CreateDirectory, QLineEdit). There should also be a warning in the console telling you that there is something wrong.
Please, have a look at the Qt's example, go through the basics first to create your widgets and signal/slots interaction. It will be then easier to include your business logic.
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Hi, Thank you for your help.
It works great.1)Nevertheless I had to erase the instruction about the destructor in fenetre.h.
// ~fenetre();
What can I do to keep a destructor declaration in the fenetre header?2)in monslot(), since this.hide doesn't kill the object, may I use 'this.destroy' before creating the new fenetre-class object?
@
this.destroy;
fenetre *h = new fenetre(rep);
h->setGeometry(00,100,300,300);
h->show();
@3)After creating the files named nom1 (nom2,...) I would like to add the instructions below:
Is this bit of code acceptable?@ bool ok = output.open(QFile::WriteOnly|QFile::Text); if (ok) { QTextStream stream(&output); stream.setIntegerBase(10); stream.setCodec("UTF-8"); stream << "info: " << line->text() << "\n\n"; stream << "info2 " << line2->text() << "\n\n"; stream.flush(); output.close(); } else { qDebug("Impossible d'ouvrir le fichier txt"); } @ 4) In fact I would like to create a html file. Can I keep the above code? -
[quote author="phil63" date="1371230754"]1)Nevertheless I had to erase the instruction about the destructor in fenetre.h.
// ~fenetre();[/quote]Why?[quote]2)in monslot(), since this.hide doesn't kill the object, may I use 'this.destroy' before creating the new fenetre-class object?
@
this.destroy;
fenetre *h = new fenetre(rep);
h->setGeometry(00,100,300,300);
h->show();
@
[/quote]A few things small things first:There is no destroy() function, only deleteLater().
"this" is a pointer, you'll need to write "this->function()", not "this.function()"
But more importantly, there's no need to create a new one and delete the old one. Just update the old one.
[quote]3)After creating the files named nom1 (nom2,...) I would like to add the instructions below:
Is this bit of code acceptable?@ bool ok = output.open(QFile::WriteOnly|QFile::Text); if (ok) { QTextStream stream(&output); stream.setIntegerBase(10); stream.setCodec("UTF-8"); stream << "info: " << line->text() << "\n\n"; stream << "info2 " << line2->text() << "\n\n"; stream.flush(); output.close(); } else { qDebug("Impossible d'ouvrir le fichier txt"); } @[/quote]That looks fine. Since you already wrote the code, you can test it yourself -- it's faster than asking here :)
[quote]4) In fact I would like to create a html file. Can I keep the above code?[/quote]Yes, but you need to write extra code to convert your input text into a HTML document (for example, adding tags like <html></html>, <body></body>, etc.)
