Resizing a QMessageBox?

[wagmare]

check if QMessageBox::showEvent() may block the resize event ... qt version ..

[Caius Aérobus]

The resize() does not work, I checked QMessageBox::showEvent() but nothing special, and QMessageBox::resizeEvent() just calls QDialog::resizeEvent(). So except if dialogs does not allow resize events, I do not understand why I can't resize my QMessageBox.
I use Qt-4.5 on Max OS X Leopard.

[wysota]

It probably has a constraint set on its layout. One way or another - what is the reason for wanting to resize the dialog? Also maybe it's easier to create your own one from scratch?

[Caius Aérobus]

Just because my text is too long and QMessageBox resizes its height accordingly and I simply cannot read the end of my text.
Ok I can rewrite anything from scratch but I expect from Qt some easier way to achieve things and being able to resize a window did not appear as a so difficult task lol

[wysota]

Have you tried simply wrapping your text into a paragraph tag?

#include <QMessageBox>
#include <QApplication>
 
int main(int argc, char **argv){
  QApplication app(argc, argv);
  QMessageBox::information(0, "caption", "<p>A very (...) long text</p>");
}

#include <QMessageBox>
#include <QApplication>

int main(int argc, char **argv){
  QApplication app(argc, argv);
  QMessageBox::information(0, "caption", "<p>A very (...) long text</p>");
}

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[Caius Aérobus]

This is exactly what I did first. But since the window was too long, I tried to instanciate a new QMessageBox so as to be able to enlarge it.

[wysota]

Doesn't QMessageBox break the text for you?

[Caius Aérobus]

Doesn't QMessageBox break the text for you?

No, the window is simply too high and its bottom goes beyond the bottom of my screen.

[wysota]

Did it come to your mind that you may simply be trying to fit too much text into the message box? It is meant for short messages, not esseys. Maybe a custom dialog with QPlainTextEdit or QTextBrowser would be better in your case?

[ptorrance]

A really nasty hack to make QMessageBox resizable by overriding QMessageBox::event().

The following code resets min/max heights and size policys of the derived QMessageBox on EVERY event calls.
It is slow, but it does work...

MyMessageBox::MyMessageBox() : QMessageBox()
{
     setSizeGripEnabled(true);
}
 
bool MyMessageBox::event(QEvent *e)
{
    bool result = QMessageBox::event(e);
 
    setMinimumHeight(0);
    setMaximumHeight(QWIDGETSIZE_MAX);
    setSizePolicy(QSizePolicy::Expanding,QSizePolicy::Expanding);
 
    // make the detailed text expanding 
    QTextEdit *textEdit = findChild<QTextEdit *>();
 
    if(textEdit)
    {
        textEdit->setMinimumHeight(0);
        textEdit->setMaximumHeight(QWIDGETSIZE_MAX);
        textEdit->setSizePolicy(QSizePolicy::Expanding,QSizePolicy::Expanding);
    }
 
    return result;
}

MyMessageBox::MyMessageBox() : QMessageBox()
{
     setSizeGripEnabled(true);
}

bool MyMessageBox::event(QEvent *e)
{
    bool result = QMessageBox::event(e);

    setMinimumHeight(0);
    setMaximumHeight(QWIDGETSIZE_MAX);
    setSizePolicy(QSizePolicy::Expanding,QSizePolicy::Expanding);

    // make the detailed text expanding 
    QTextEdit *textEdit = findChild<QTextEdit *>();

    if(textEdit)
    {
        textEdit->setMinimumHeight(0);
        textEdit->setMaximumHeight(QWIDGETSIZE_MAX);
        textEdit->setSizePolicy(QSizePolicy::Expanding,QSizePolicy::Expanding);
    }

    return result;
}

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[Tomasz]

I was searching for something like that. How should *.h file look?

thanks in advance
best regards
Tomasz

[wysota]

I really would avoid using this code. Is seems awfully incorrect to me to force resize of the message box upon any possible event received. To be honest I don't have any problem in fitting large amount of text into a message box without any code manipulations to QMessageBox. Especially that there is QMessageBox::setDetailedText()