QTabWidget set current tab by tab name?

lansing

I have a QTabWidget and I added new tabs to it by this:

m_ui->myTabWidget->addTab(filterWidget, tabName);

I want to set current tab widget by tab name instead of index. Now the first thing I need to do it to find the index, but I don't know how. I found something online like this inside a custom QTabWidget but it doesn't work, and a qDebug return many names except for the one I entered.

    foreach (QWidget* child, findChildren<QWidget*>()) {
        if (child->objectName() == _tabName)
        {
            qDebug() << child->objectName();
            setCurrentIndex(indexOf(child));
        }
    }

jsulm

@lansing said in QTabWidget set current tab by tab name?:

child->objectName()

This returns object name which is completely unrelated to tabName which is a text label.
Why do you want to activate a tab using its text label which will be different when translated to another language?
You can activate using the widget you're inserting via addTab (https://doc.qt.io/qt-5/qtabwidget.html#indexOf).

Bonnie

for(int i = 0; i < count(); i++) {
    if(tabText(i) == _tabName) {
        setCurrentIndex(i);
        break;
    }
}

But this is not a good design, as @jsulm said.

lansing

@jsulm

I have this QTabWidget tied to the QComboBox on another dialog sharing the same tab name. If the tabwidget changed, the combobox will also changed and vise versa. I also have functions that remove and add new items to this tabwidget/combobox as well as allowing reordering of tab, so I can't connect them through the same index, I have to connect them by names.

I have a slot catching the signal on the combobo change, and in the slot I have retrieved my widget through std::find_if with a lamda expression. But when I use it with indexof() I got the error

error: cannot initialize a parameter of type 'QWidget *' with an lvalue of type 'QVector<FilterWidget>::iterator' (aka 'FilterWidget*')

jsulm

@lansing Then why not use index from https://doc.qt.io/qt-5/qcombobox.html#activated to activate the tab?

"But when I use it with indexof() I got the error" - well, I guess (you don't show the code) that you forgot to dereference the iterator when calling indexOf...

lansing

@jsulm said in QTabWidget set current tab by tab name?:

dereference the iterator

This is my slot catching the combobox signal, I don't know how to dereference it

    auto pred = [tabName](const FilterWidget &item) {
        return item.tabName== tabName;
    };

    QVector<FilterWidget>::iterator it =
            std::find_if(std::begin(m_filterWidgetVector),
                         std::end(m_filterWidgetVector), pred);

    if (it != std::end(m_filterWidgetVector)) {         
        int foundIndex = m_ui->myTabWidget->indexOf(it);
        m_ui->myTabWidget->setCurrentIndex(foundIndex);

JonB

@lansing said in QTabWidget set current tab by tab name?:

int foundIndex = m_ui->myTabWidget->indexOf(it);

int foundIndex = m_ui->myTabWidget->indexOf(*it);

On a separate note, I don't mean to confuse you but:

QVector<FilterWidget>

Assuming your FilterWidget really is a QWidget, it would be more usual to store pointers to widgets, QVector<FilterWidget *>, but I don't know what the rest of your code for this looks like....

lansing

@JonB

I got the error

error: no viable conversion from 'FilterWidget' to 'QWidget *'
qtabwidget.h:107:26: note: passing argument to parameter 'widget' here

JonB

@lansing
I have already answered that in the second part of my post.
You really ought know what you're doing with QWidgets versus QWidget *s instead of randomly tyrying things and getting errors, basic C++.

Without correcting that (which I think you should, but as I said that's a separate matter), I am not sure but you may be able to make it work from where you are now via

int foundIndex = m_ui->myTabWidget->indexOf(&*it);

lansing

@JonB

The FilterWidget is a struct storing a few widgets and some properties, those widgets has pointers.

struct FilterWidget {
    ImageFilter* imageFilter; 
    TextFilter* textFilter;
    QString tabName;
};

QVector<FilterWidget> m_filterWidgetVector;

indexOf(&*it) returns the error

error: cannot initialize a parameter of type 'QWidget *' with an rvalue of type 'FilterWidget *'

JonB

@lansing
Then I give up. I don't know what you think you are doing. You know that myTabWidget->indexOf() takes a QWidget * as the widget to try to find, and you are passing it some struct (which you have unadvisedly chosen to name FilterWidget [and also how can you possibly make a member named tabName as of type int?]) that has nothing to do with a widget, so how do you expect it to work? Like I wrote, you're not supposed to bung random things in and see what happens, you really need to understand what is going on to write the correct code....

lansing

@JonB

Then tell me what did I do wrong except naming the struct with the "widget" name? The int tabName is a typo.

mrjj

@lansing
Hi
The indexOf can find the widgets you insert to tabWidget with
m_ui->myTabWidget->addTab(filterWidget, tabName);

so you can find that index again with m_ui->myTabWidget->indexof(filterWidget)

struct FilterWidget cannot be used in this context.

But i wonder how
ImageFilter* imageFilter;
TextFilter* textFilter;
relates to the filterWidget you use with addTab
is it store in imagefilter or textfilter?

lansing

@mrjj

Hi, the tabs are added with the ImageFilter class with a tab name

mrjj

@lansing
Ok so from a FilterWidget item you can find the
tab index by
m_ui->myTabWidget->indexof(filterWidgetENTRY.imageFilter )
or
int foundIndex = m_ui->myTabWidget->indexOf(it.imageFilter ); // maybe need * in front

jsulm

This post is deleted!

lansing

@mrjj

Thanks the second one works!