Layout, widgets not inside ???

SPlatten

I have an XML file where I have added a group box, the group box has an attribute layout:

<groupbox id="enSEX" eol="true" align="left" layout="vertical" 
	  dbfield="vcSex">
    <radiobutton id="rdoM" text="Male" default="true" position="0,0"/>
    <radiobutton id="rdoF" text="Female" position="1,0"/>
</groupbox>

In my common node code:

    if ( mstrName.compare(clsCNT::mscszGroupBox) == 0 ) {
//Any layout specified?
        QString strLayout(strGetAttribute(clsXMLnode::mscszAttrLayout));
        if ( strLayout.compare(clsXMLnode::mscszLayoutGrid) == 0 ) {
            mpobjLayout = new QGridLayout;
        } else if ( strLayout.compare(clsXMLnode::mscszLayoutHorizontal) == 0 ) {
            mpobjLayout = new QHBoxLayout;
        } else if ( strLayout.compare(clsXMLnode::mscszLayoutVertical) == 0 ) {
            mpobjLayout = new QVBoxLayout;
        }
    }

mpobjLayout is initialised to nullptr in the constructor. mpobjLayout is defined in the class as:

QLayout* mpobjLayout;

At the end of the node constructor:

    if ( mpobjParent != nullptr ) {
//Update the parent adding 'this' node to it's child list
        mpobjParent->appendChild(this);
//Is the parent a group box?
        if ( mpobjParent->cstrGetNodeName().compare(clsCNT::mscszGroupBox) == 0 ) {
//Yes, does it have a layout?
            QLayout* pobjLayout(mpobjParent->pobjGetLayout());
            if ( pobjLayout != nullptr ) {
//Yes, add this widget to the parent layout
                QWidget* pobjWidget(pobjGetWidget());
                if ( pobjWidget != nullptr ) {
                    pobjLayout->addWidget(pobjWidget);
                }
            }
        }
    }

For some reason which I don't quite understand I am seeing:

Why are the radio buttons not in the group box?

I should add in the group box widget constructor:

    if ( mpobjNode != nullptr ) {
        QLayout* pobjLayout(mpobjNode->pobjGetLayout());
        if ( pobjLayout != nullptr ) {
            setLayout(pobjLayout);
        }
    }

SGaist

Hi,

For quick debugging purpose you should print the pointer value of each object you test to ensure you are not passing in the else clause unexpectedly.

SPlatten

@SGaist , I'm not really sure what or how this would help? I'm checking the pointers everywhere before use.

mrjj

@SPlatten
Hi
What parent do you assign the radio buttons?

QWidget* pobjWidget(pobjGetWidget());

SPlatten

@mrjj , in my XML file:

<groupbox id="enSEX" eol="true" align="left" layout="vertical" 
	  dbfield="vcSex">
	<radiobutton id="rdoM" text="Male" default="true" position="0,0"/>
	<radiobutton id="rdoF" text="Female" position="1,0"/>
</groupbox>

Where groupbox results in a QGroupBox being created and each radiobutton results in a QRadioButton.

In my class constructor for clsQtGroupBox which is derived from QGroupBox I check the node attribute and create a layout if specified:

QString strLayout(mpobjNode->strGetAttribute(clsXMLnode::mscszAttrLayout));
if ( strLayout.compare(clsXMLnode::mscszLayoutGrid) == 0 ) {
    mpobjNode->mpobjLayout = new QGridLayout(pParent);
} else if ( strLayout.compare(clsXMLnode::mscszLayoutHorizontal) == 0 ) {
    mpobjNode->mpobjLayout = new QHBoxLayout(pParent);
} else if ( strLayout.compare(clsXMLnode::mscszLayoutVertical) == 0 ) {
    mpobjNode->mpobjLayout = new QVBoxLayout(pParent);
}
if ( mpobjNode->mpobjLayout != nullptr ) {
    setLayout(mpobjNode->mpobjLayout);
}

mpobjLayout is initialised to nullptr in the mpobjNode constructor. I've checked the source in debug and each radio button has the QGroupBox as a parent.

I think this could be the problem as looking at:
https://doc.qt.io/qt-5/qtwidgets-widgets-groupbox-example.html

It looks like the parent of the radio buttons should be the layout not the group box.

After creating the layout I can see that mpobjLayout is not nullptr.

Calling mpobjLayout->widget() returns nullptr, why?
Could it be because mpobjLayout is defined as QLayout?

I thought this should be compatible with QGridLayout, QHBoxLayout and QVBoxLayout since
QGridLayout is derived from QLayout
QHBoxLayout and QVBoxLayout are derived from QBoxLayout which is derived from QLayout.

SGaist

@SPlatten said in Layout, widgets not inside ???:

QString strLayout(mpobjNode->strGetAttribute(clsXMLnode::mscszAttrLayout));
if ( strLayout.compare(clsXMLnode::mscszLayoutGrid) == 0 ) {
mpobjNode->mpobjLayout = new QGridLayout(pParent);
} else if ( strLayout.compare(clsXMLnode::mscszLayoutHorizontal) == 0 ) {
mpobjNode->mpobjLayout = new QHBoxLayout(pParent);
} else if ( strLayout.compare(clsXMLnode::mscszLayoutVertical) == 0 ) {
mpobjNode->mpobjLayout = new QVBoxLayout(pParent);
}
if ( mpobjNode->mpobjLayout != nullptr ) {
setLayout(mpobjNode->mpobjLayout);
}

You know that passing a parent to a layout automatically applies that layout on the parent given ?

Following the logic of that block of code, you should replace pParent by this and drop the last if.

SPlatten

@SGaist , I've modified the source and tested again, still the same result:

QString strLayout(mpobjNode->strGetAttribute(clsXMLnode::mscszAttrLayout));
if ( strLayout.isEmpty() != true ) {
    QWidget* pobjWidget(mpobjNode->pobjGetWidget());
    if ( pobjWidget != nullptr ) {
        if ( strLayout.compare(clsXMLnode::mscszLayoutGrid) == 0 ) {
            mpobjNode->mpobjLayout = new QGridLayout(pobjWidget);
        } else if ( strLayout.compare(clsXMLnode::mscszLayoutHorizontal) == 0 ) {
            mpobjNode->mpobjLayout = new QHBoxLayout(pobjWidget);
        } else if ( strLayout.compare(clsXMLnode::mscszLayoutVertical) == 0 ) {
            mpobjNode->mpobjLayout = new QVBoxLayout(pobjWidget);
        }
    }
}

In the above code:
this points to the an instance of clsQtGroupBox.
mpobjNode is a pointer to the XML node, in this case groupbox.
pobjWidget is a pointer to the instance of QGroupBox.
mpobjLayout is a pointer to the layout created using the pobjWidget as a parent.

Later in the code where the radio buttons or other nodes are created and added to parents:

 if ( mpobjParent != nullptr ) {
    bool blnAppend(true);
//Does the parent node have a layout?
    QLayout* pobjLayout(mpobjParent->pobjGetLayout());
    if ( pobjLayout != nullptr ) {
//Yes, add this widget to the layout
        QWidget* pobjWidget(pobjGetWidget());
        if ( pobjWidget != nullptr ) {
            pobjLayout->addWidget(pobjWidget);
            blnAppend = false;
        }
    }
//Update the parent adding 'this' node to it's child list
    mpobjParent->appendChild(this, blnAppend);
}

this points to an instance of clsQtRadioButton
mpobjParent is a pointer to the parent clsQtGroupBox
pobjLayout is a pointer to the layout QLayout created in the previous section.
pobjWidget is a pointer to QRadioButton widget

Unfortunately this still results in:
Screenshot 2021-10-17 at 08.13.40.png

SGaist

The issue I am seeing here is that your children widgets seems to need to know stuff about their parent. Why ?

Following a top down approach, you start with the "master" widget that for example is your QGroupBox, add a layout to it, then next step, add the two QRadioButtons one after the other.

If that group box is inside another widget, then it's not its problem. The positioning within a parent widget's layout or in coordinates is the responsibility of said parent.

Publicnamer

@SGaist I would just like to point out that in many cases manual layout of widgets saves a lot of development time and the code is perfectly understandable (unless sloppily written). The present-day focus on XML layout is a fad that is wasting a lot of people's time.

JKSH

@Publicnamer said in Layout, widgets not inside ???:

I would just like to point out that in many cases manual layout of widgets saves a lot of development time and the code is perfectly understandable (unless sloppily written). The present-day focus on XML layout is a fad that is wasting a lot of people's time.

For small projects, perhaps.

I, for one, find that a WYSIWYG editor helps me get my GUI up and running faster than manually coding its layouts in C++. And for very large projects, it's helpful to enable a front-end designer and back-end developer to work in parallel.

Please note that to OP's use-case is not the same as how we typically use XML .ui files in Qt. It is definitely not our "present-day focus".

AxelVienna

If you want to know if your QRadioButtons are inside our outside your layout, obtain and print the pointers upon creation. At the end of your code, read the widget pointers of your layout and compare them like that:

for (int i = 0; i < yourLayout->count(); ++i)
{
  QWidget *widget = gridLayout->itemAt(i)->widget();
  // qdebug or cout the pointer or write it to a vector
}

That is the only way to figure out if there is a bug in your complex code or a Qt misbehavior.

SPlatten

@AxelVienna , I modified my code setting the objectName for each widget I then added:

        if ( pobjWidget != nullptr ) {
//Set the object name
            QString strID(strGetAttribute(clsXMLnode::mscszAttrID)),
                    strName(mstrName);
            if ( strID.isEmpty() != true ) {
                strName += ", id: " + strID;
            }
            pobjWidget->setObjectName(strName);
        }
        if ( pobjParent != nullptr && pobjParent->mpobjLayout != nullptr ) {
            pobjParent->mpobjLayout->addWidget(pobjWidget);
            for (int i = 0; i < pobjParent->mpobjLayout->count(); ++i) {
              QWidget *widget = pobjParent->mpobjLayout->itemAt(i)->widget();
              QString strWidget(widget->objectName()), strParent(widget->parentWidget()->objectName());
qDebug() << strWidget << ", parent: " << strParent;
            }
        }

I checked in the debugger and strWidget is exactly what I expected to see, but there is still no difference in the output.

In the above the output is:

radiobutton, id: rdoM, parent: groupbox, id: enSEX
radiobutton, id: rdoF, parent: groupbox, id: enSEX

This is using the XML:

<groupbox id="enSEX" eol="true" align="left" layout="vertical" 
		     dbfield="vcSex">
	<radiobutton id="rdoM" text="Male" default="true" position="0,0"/>
	<radiobutton id="rdoF" text="Female" position="1,0"/>
</groupbox>

The debug output looks correct, but the screen still looks the same.

AxelVienna

As @Publicnamer said, creating an UI fully programmatically takes time and creates fuzz. Your debugging just tells us that two radio buttons are inside a group box. You have to look at the pointers themselves to make sure your layout is really the I’m your group box and the radio buttons are the ones you mean.

SPlatten

@AxelVienna , time is what I have, I know the nodes are correct, I used the information on this page as a guide:
https://doc.qt.io/qt-5/qtwidgets-widgets-groupbox-example.html

    QGroupBox *groupBox = new QGroupBox(tr("Exclusive Radio Buttons"));

    QRadioButton *radio1 = new QRadioButton(tr("&Radio button 1"));
    QRadioButton *radio2 = new QRadioButton(tr("R&adio button 2"));
    QRadioButton *radio3 = new QRadioButton(tr("Ra&dio button 3"));

    radio1->setChecked(true);
    QVBoxLayout *vbox = new QVBoxLayout;
    vbox->addWidget(radio1);
    vbox->addWidget(radio2);
    vbox->addWidget(radio3);
    vbox->addStretch(1);
    groupBox->setLayout(vbox);

    return groupBox;
}

My clsQtGroupBox is derived from my clsXMLnode class, this class has a member called mpobjLayout which is created when the node has a layout attribute. The group box node has a layout attribute and thats why it has a layout, if the parent of the radio buttons has a layout then they are added to the layout and the layout is set as the layout of the group box. I just can't see how my code differs from the example.

Each instance of clsXMLnode has a QWidget which is QGroupBox, QRadioButton etc.

AxelVienna

@SPlatten said in Layout, widgets not inside ???:

if the parent of the radio buttons has a layout then they are added to the layout

That may be the problem. What if the parent hasn’t got a layout (yet)? Does your code throw an exception, returns an error or just stops? Or does it place the buttons outside the group box? I tend to believe that your code provokes the behaviour since I have never seen a bug in Qt that fiddles with widget assignments.

SPlatten

@AxelVienna , I manage everything, only the nodes I add have widgets and only the widgets I assign a layout have a layout… unless QT is doing something I’m not aware of.

AxelVienna

A bold statement…. A lot of volunteers have read through your posts, tried to help and advise. If there are reasons to maintain your approach and you can’t find the bug, you have to hire an expert.

SGaist

@SPlatten said in Layout, widgets not inside ???:

I just can't see how my code differs from the example.

Parent handling from child widgets, that's the main difference I already suggested to avoid.

JoeCFD

@SPlatten said in Layout, widgets not inside ???:

QGroupBox *groupBox = new QGroupBox(tr("Exclusive Radio Buttons"));

QRadioButton *radio1 = new QRadioButton(tr("&Radio button 1"));
QRadioButton *radio2 = new QRadioButton(tr("R&adio button 2"));
QRadioButton *radio3 = new QRadioButton(tr("Ra&dio button 3"));

radio1->setChecked(true);
QVBoxLayout *vbox = new QVBoxLayout;
vbox->addWidget(radio1);
vbox->addWidget(radio2);
vbox->addWidget(radio3);
vbox->addStretch(1);
groupBox->setLayout(vbox);

return groupBox;

    auto groupBox = new QGroupBox(tr("Exclusive Radio Buttons"), this );

    auto radio1 = new QRadioButton(tr("&Radio button 1"), groupBox);
    auto radio2 = new QRadioButton(tr("R&adio button 2"), groupBox);
    auto radio3 = new QRadioButton(tr("Ra&dio button 3"), groupBox);

    auto button_group = new QButtonGroup;
    button_group->addButton(radio1) ; 
    button_group->addButton(radio2) ;
    button_group->addButton(radio3) ;
    button_group->setExclusive( true );
    radio1->setChecked(true);

    auto vbox = new QVBoxLayout( groupBox );
    vbox->addWidget(radio1);
    vbox->addWidget(radio2);
    vbox->addWidget(radio3);
    vbox->addStretch(1);

    return groupBox;

JoeCFD

    QString group_style_sheet = QString("QGroupBox{border: %1px solid gray;border-radius: %2px;margin-top: %3px;}" )
                                                                         .arg( m_groupBorderThickness )
                                                                        .arg( m_groupBorderRadius )
                                                                        .arg( text_font_size * 1.6 );

Also you may need to set group style sheet to move text to the top of group frame. I do use it. Otherwise, the title text may push the radio buttons out of the group frame. Set minimum height to your group box.
If you do not want to set border properties, it is OK. But it is better to set margin top which is related to your group font size. Play with font size and parameter 1.6 and you will be able to move the radio buttons into the group frame.