Ctd when accessing Ui::MainWindow from another class

pditty8811

Here is the class right here. I'm trying to get the buttongroup to hide but when it fires I get a ctd.

uninstall.h
@
#ifndef UNINSTALL_H
#define UNINSTALL_H

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include "uninstall.h"

class Uninstall
{
public:
Uninstall();
void hide();

private:
Ui::MainWindow *ui;

};

#endif // UNINSTALL_H
@

uninstall.cpp
@

Uninstall::Uninstall()
{
MainWindow *mw = new MainWindow();

}

void Uninstall::hide() {

ui->buttonWidget->hide();

}@

MainWindow.cpp

@

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include "uninstall.h"

MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{

ui->setupUi(this);

}

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

void MainWindow::on_pushButton_Next_clicked()
{
Uninstall *uninstallObj;

if (ui->radioButton_Uninstall->isChecked()) {

    uninstallObj->hide();

}

}

Ui::MainWindow* MainWindow::getUi()
{
return ui;
}

@

dheerendra

@Uninstall *uninstallObj;
if (ui->radioButton_Uninstall->isChecked()) {

    uninstallObj->hide();@

Your uninstallObj is not initialised. So it will crash. Also what is ctd ?

ankursaxena

I think, Here uninstallObj->show(); is missing. then uninstallObj->hide(); should not work.

pditty8811

[quote author="Dheerendra" date="1403675821"]
@Uninstall *uninstallObj;
if (ui->radioButton_Uninstall->isChecked()) {

    uninstallObj->hide();@

Your uninstallObj is not initialised. So it will crash. Also what is ctd ? [/quote]
ctd stand for crash to desktop.
That didn't fix issue.

pditty8811

[quote author="ankursaxena" date="1403681027"]I think, Here uninstallObj->show(); is missing. then uninstallObj->hide(); should not work.
[/quote]

That can't be right because hide() is a method I created in class Uninstall, its not a property.

ankursaxena

Oh. I haven't noticed that

ankursaxena

but you should avoid such kind of nomination . It creates confusion and can be error-prone.

IamSumit

the best way to identify the ctd is to use qDebug() statemnts ,
Try it. then you can find the place where is crash starting.

pditty8811

[quote author="IamSumit" date="1403686743"]the best way to identify the ctd is to use qDebug() statemnts ,
Try it. then you can find the place where is crash starting.[/quote]

I'm able to get information from Ui::MainWindow, like text from labels, but I am not able to adjust properties of Ui::MainWindow in class Uninstall.

What's the deal?

p3c0

Hi,

You should create a new Uninstall object.
*uninstallObj is a pointer and it points to nothing in your case and hence the seg fault.
Do this,
@
Uninstall *uninstallObj = new Uninstall;
@

pditty8811

[quote author="p3c0" date="1403690252"]Hi,

You should create a new Uninstall object.
*uninstallObj is a pointer and it points to nothing in your case and hence the seg fault.
Do this,
@
Uninstall *uninstallObj = new Uninstall;
@[/quote]

That's not it. I can get to the Uninstall class successfully. I test uing qDebug.

I just can't change properties of Ui::MainWindow from within Uninstall. weird. However I can print
qDebug << Ui::MainWindow->QLabel->text();
From within Uninstall class

p3c0

So is the crashing issue solved ?
For changing properties from one class to other i would suggest you to use "Signals and Slots mechanism":http://qt-project.org/doc/qt-4.8/signalsandslots.html.

pditty8811

[quote author="p3c0" date="1403692659"]So is the crashing issue solved ?
For changing properties from one class to other i would suggest you to use "Signals and Slots mechanism":http://qt-project.org/doc/qt-4.8/signalsandslots.html.[/quote]

No its not solved.

pditty8811

I'm still having trouble with this. Could someone show me a simple example of transfering *ui to another class using signals and slots?

IamSumit

Hi
If your problem is still there
take a look on the following link
http://qt-project.org/doc/qt-4.8/designer-using-a-ui-file.html
hope it helps :)