Accessing widgets from another form

qtTwist

I'm pretty new to c++ and qt. I want to make a debug console which is accessible from my main window and all other dialogs in my application

My debug console has an QPlainTextEdit widget on it here's the code for debugConsole.h:
@#ifndef DEBUGCONSOLE_H
#define DEBUGCONSOLE_H

#include <QString>
#include <QDialog>

namespace Ui {
class debugConsole;
}

class debugConsole : public QDialog
{
Q_OBJECT

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

void sendDbgOutput(QString output);

private:
Ui::debugConsole *ui;
};

#endif // DEBUGCONSOLE_H@

and here's the code for debugConsole.cpp:
@#include "debugconsole.h"
#include "ui_debugconsole.h"

debugConsole::debugConsole(QWidget *parent) :
QDialog(parent),
ui(new Ui::debugConsole)
{
Qt::WindowFlags flags = windowFlags() ;
flags |= Qt::CustomizeWindowHint ;
flags &= ~Qt::WindowCloseButtonHint ;
setWindowFlags(flags);
ui->setupUi(this);
}

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

void debugConsole::sendDbgOutput(QString output)
{
ui->debugOutput->appendPlainText(output);
}
@

from my mainwindow.cpp I include debugConsole.h like such:
@#include "debugconsole.h"@

then, I do this here:
@debugConsole *dbgConsole;@

now when I try to call it like this, my program crashes:
@void MainWindow::captureEnabled()
{
if(ui->captureSlider->value() == 1)
{
capturing = true;
ui->captureLabel->setText("YES");
ui->captureLabel->repaint();
dbgConsole->sendDbgOutput("Capture Enabled");
}
else
{
capturing = false;
ui->captureLabel->setText("NO");
ui->captureLabel->repaint();
}
}@

what am i doing wrong/not doing at all?

AcerExtensa

@debugConsole *dbgConsole = new debugConsole(this);@
instead of:
@debugConsole *dbgConsole;@

qtTwist

ok, I know i'm going to look pretty stupid for this.

but when I put that at the top of mainwindow.cpp

I get the error, "invalid use of 'this' at top level"

but, if i put it inside of any other function it won't let me use it?

AcerExtensa

in your debugConsole constructor, QWidget pointer is needed as parent widget. I have assumed what you are instantiating debugConsole instance inside some kind of main widget class.
@debugConsole::debugConsole(QWidget *parent)@

You can create instance of debugConsole without setting parent QWidget pointer.
@debugConsole *dbgConsole = new debugConsole(NULL);@

qtTwist

i tried that but, I get a microsoft visual c++ runtime error

AcerExtensa

bq. i tried that but, I get a microsoft visual c++ runtime error

It has nothing todo with debugConsole constructor... Code which causes program to fail is somewhere else...

@debugConsole::debugConsole(QWidget *parent) :
QDialog(parent),
ui(new Ui::debugConsole)
{
Qt::WindowFlags flags = windowFlags() ;
flags |= Qt::CustomizeWindowHint ;
flags &= ~Qt::WindowCloseButtonHint ;
setWindowFlags(flags);
ui->setupUi(this);
}@

qtTwist

ahhh, well thanks..

Instead of reading a book I decided to jump right into programming and ask for help when I get stuck, so I'm sorry for being kind of an idiot.

AcerExtensa

No problem... There's nothing shameful about being a beginner....

Jimmy Crab

My solution is to make "ui" public:

//sub window: Form3PType1
public:
    Ui::Form3PType1 *ui;

//main window: FormCL3P
qDebug() << "ANo: " << G::form3PType1->ui->tbxANo->toPlainText();

output: ANo: "A5"

When the "ui" of a window is public, it can be accessed from other cpp.
Works for me.