updating radio buttons programmatically

Pablo J. Rogina

@mzimmers said in updating radio buttons programmatically:

I use a QDataWidgetMapper object in my dialog

having stated this from the very beginning should have saved time and effort, and allow us to narrow down the issue... :-)

Given that said, maybe this post may help

mzimmers

@Pablo-J.-Rogina said in updating radio buttons programmatically:

@mzimmers said in updating radio buttons programmatically:

I use a QDataWidgetMapper object in my dialog

having stated this from the very beginning should have saved time and effort, and allow us to narrow down the issue... :-)

Sorry -- I thought I had done so here:
https://forum.qt.io/topic/93723/updating-radio-buttons-programmatically/4

In any event, it may be time to consider a different approach.

SGaist: looking at your response, I have a couple questions:

you mention customizing my address type widget - are you referring to the buttongroup?
What do you mean by "the setter"?

SGaist

I mean make a custom widget e.g.:

class IpAddressTypeWidget : public Widget
{
    Q_OBJECT
    Q_PROPERTY(QString addressType GET addressType SET setAddressType NOTIFY addressTypeChanged USER true)

public:
    explicit IpAddressTypeWidget(QWidget *parent=nullptr);

    QString addressType() const;

signals:
    void addressTypeChanged(const QString& type);

public slots:
    void setAddressType(const QString& type);
};

In setAddressType, you update the radio buttons based on the string given. Note that you can also use an enum and it's the role of the parser to use the correct enum when changing the address type. It would be cleaner but for a first round, it might be easier to use a QString.

mzimmers

OK, I think I understand what you're suggesting, but some of the mechanics still aren't clear to me.

Does this new widget replace any of my existing widgets, or does it just exist (invisibly) within my dialog?

Do I need to pass it my ui pointer at construction to give it access to the rest of the widgets?

SGaist

It's an independent widget where you put your QGroupBox which contains the two QRadioButton.

mzimmers

I'm still wading through this, but I did discover a necessary change in the Q_PROPERTY macro:

    Q_PROPERTY(QString ipSource READ ipSource WRITE SetIpSource NOTIFY ipSourceChanged USER true)

It wouldn't compile with the GET/SET terms.

mzimmers

SGaist: in your example above, where does the signal come from that connects to the slot setAddressType()?

SGaist

IIRC, you are using a QDataWidgetMapper for that editor ? Correct, then with that definition, when you call addMapping it will use that property to get and set the data from that widget in the same manner as it does for QLineEdit or QSpinBox.

mzimmers

OK, I think I get this in principle. From an implementation standpoint, how/when should the edit dialog retrieve this information from the custom widget -- another signal/slot?

Thanks...

SGaist

I'm not sure I'm following you here. Isn't that widget already using QDataWidgetMapper ?

mzimmers

Yes:

in editdialog.cpp

IpSourceWidget m_isw; // IpSourceWidget is my custom widget
m_mapper->addMapping(&m_isw, TAG_IP_CONFIG_SRC);

But don't I still have to use this to update the group box? Like this:

    if (qs.toStdString() == IP_SOURCE_TXT[IP_SOURCE_DHCP])
    {
        ui->groupBoxIpAssignment->setChecked(IP_SOURCE_DHCP);
    }
    else
    {
        ui->groupBoxIpAssignment->setChecked(IP_SOURCE_STATIC);
    }

EDIT: OK, that wasn't right. I changed it to this:

 QButtonGroup *m_qbg;    // button group for IP source selection.
 ...
 if (qs.toStdString() == IP_SOURCE_TXT[IP_SOURCE_DHCP])
{
    m_qbg->button(IP_SOURCE_DHCP)->setChecked(true);
}
else
{
    m_qbg->button(IP_SOURCE_STATIC)->setChecked(true);
}

This at least gets the correct value displaying in the edit dialog. Still not sure I'm really doing this right, though.

SGaist

Don't forget to emit the corresponding notification signal if the address type has changed.

mzimmers

Not sure I understand. The code above is in a slot in my edit dialog. Elsewhere I have a connect:

IpSourceWidget *m_isw;
...
QObject::connect(m_isw, &IpSourceWidget::ipSourceChanged, this, &EditDialog::updateIpSource);

Is this the signal you're referring to?

SGaist

I was thinking about where you are emitting ipSourceChanged.

mzimmers

Well, maybe that's part of the problem...I wasn't aware I needed to use that signal.

I'm still feeling my way through this. My IpSource widget doesn't contain any display items; it just handles the model updating. It communicates with the edit dialog through some shared variables:

IpSourceWidget::IpSourceWidget(QWidget *parent, DeviceModel *d, QModelIndex *qmi) :
    QWidget(parent), m_d(d), m_qmi(qmi)
{
}

IpSourceWidget::~IpSourceWidget()
{
}

QString IpSourceWidget::ipSource() const
{
    return QString::fromStdString(IP_SOURCE_TXT[m_ics]);
}

void IpSourceWidget::setIpSource(const QString &source)
{
    m_d->getModel()->setData(*m_qmi, source);
}

I'm getting unexpected results, though. For example, after I press my "commit" button, the argument passed into setIpSource is set to "false." No idea where that's coming from.

SGaist

Why does IpSourceWidget know about DeviceModel and the corresponding QModelIndex ?

The idea behind that widget is that you use it the same way as the QLineEdit you have in your editor widget.

For example in a widget like QLineEdit you have something like:

void MyWidget::setMyStringProperty(const QString &newValue)
{
    if (newValue == currentValue) {
        return;
    }

    currentValue = newValue;
    // Do stuff if needed
    emit myStringPropertyValueChanged(newValue);
}

mzimmers

None of my other widgets require me to do anything other than calls to addMapping(). That's partly why this is so new to me.

In your example, is currentValue a member variable (or a persistent local), or am I obtaining it from the model? I originally thought the latter, but now I'm thinking I got it wrong.

SGaist

Most of the time, it's a member variable.

In the case of your widget, it could be something like:

void IpSourceWidget::setIpSource(const QString& ipSource)
{
    if ((ipSource == IP_SOURCE_DHCP && ui->dhcpButton->isChecked()) ||
         ipSource == IP_SOURCE_STATIC && ui->staticButton->isChecked())) {
        return;
    }

   if (ipSource == IP_SOURCE_DHCP) {
        ui->dhcpButton->setChecked(true);
   } else {
        ui->staticButton->setChecked(true);
   }
   emit ipSourceChanged(ipSource);
}

mzimmers

That all makes sense, but who consumes the signal? You've already updated the ui, so the dialog doesn't need it (that I can see).

Thanks...

EDIT: oh, and continuing with this design, I guess the ipSource widget would merely return the member variable?

SGaist

In this case, QDataWidget mapper will use it. Because you also have to implement the handling of that signal when you click on either of the radio button.

As for the getter:

QString IpSourceWidget::ipSource() const
{
    QString sourceType = "Unkown";
    if (ui->dhcpButton->isChecked() {
        sourceType = IP_SOURCE_DHCP ;
    } else {
        sourceType = IP_SOURCE_STATIC;
    }
    return sourceType;
}