QTabWidget 隐藏和显示选项卡

Question

I have some problems with QTabWidget. In case of the missing Hide functionality I have to build my own. According to the documentation I use removeTab and insertTab, but with insert Tab I have a problem to show the Tab page that is removed.

I use to add

  RibbonTabContent *ribbonTabContent = new RibbonTabContent;
  QTabWidget::addTab(ribbonTabContent, tabIcon, tabName);

To remove is use:

void Ribbon::hideTab(const QString &tabName)
{
  // Find ribbon tab
  for (int i = 0; i < count(); i++)
  {
    if (tabText(i).toLower() == tabName.toLower())
    {
       QTabWidget::removeTab(i);
      break;
    }
  }
}

Both functions are working, pWidget is always null. But now the insert function do not work well. I think there I have a problem, but do not understand my problem.

void Ribbon::showTab(const QString &tabName){

    // Find ribbon tab
    QWidget* pWidget= QTabWidget::findChild<RibbonTabContent *>(tabName);
    if(pWidget){
        QTabWidget::insertTab(2,pWidget, tabName);
    }
}

Maybe someone can help me out?

Answer 1

If you call QTabWidget::removeTab you remove the tab at the specified index from the children tree of your QTabWidget , the tab instance is not actually deleted though, so when you search for that same tab with QTabWidget::findChild you can't find it because it's not a child of your QTabWidget anymore. From the code you show I think you probably would not find it anyway since findChild searches for a widget with the specified objectName but you never set it for your tab.

A solution would be to store the removed tabs and then restore them when you please.

Assuming m_hiddenTabs is a QHash<QString, QWidget*> or QMap<QString, QWidget*> you could try something like this.

void Ribbon::hideTab(const QString &tabName)
{
  // Find ribbon tab
  for (int i = 0; i < count(); i++)
  {
    if (tabText(i).toLower() == tabName.toLower())
    {
       m_hiddenTabs.insert(tabName.toLower(), QTabWidget::widget(i));
       QTabWidget::removeTab(i);
       break;
    }
  }
}

void Ribbon::showTab(const QString &tabName){

    // Find ribbon tab
    auto tab = m_hiddenTabs.take(tabName.toLower());
    if(tab){
        QTabWidget::insertTab(2, tab, tabName);
    }
}

Answer 2

Since Qt 5.15 it is also possible to use setTabVisible :

void QTabWidget::setTabVisible(int index, bool visible)

If visible is true, the page at position index is visible; otherwise the page at position index is hidden. The page's tab is redrawn appropriately.If visible is true, the page at position index is visible; otherwise the page at position index is hidden. The page's tab is redrawn appropriately.

Answer 3

It is unfortunate that QTabBar is unable to 'hide' a tab.

Here is my very easy work-around: mark the tabs 'disabled' instead (eg ui->tabWidget->setTabEnabled(tabIndex, false); ).

Then, use stylesheets to style the "disabled" tab as entirely invisible and taking up no space:

QTabBar::tab:disabled
{
    min-width: 0px;
    max-width: 0px; 
    color: rgba(0,0,0,0);
    background-color: rgba(0,0,0,0);
}

This works near-perfectly for me, with the only downside being that you can't have both disabled and "hidden" tabs in the same tabbar. However, usually I want one or the other, not both in the same bar.