Problem with Size Policy of derived QWidget

[eehmke]

Hello,
I wrote a class following the letter-envelop idiom:
http://en.wikibooks.org/wiki/More_C+...nvelope_Letter
where the class is derived from QWidget and contains a letter class of QWidget*. I need this class as a base class for several other widgets like mylabel, mycheckbox. I created a sizeHint method like this:

QSize my_label::sizeHint () const {
return ((QLabel*)letter)->sizeHint();
}

This works so far, but one problem is unsolved: the labels are rendered using the minimum size, leaving different amount of white space at the right side. I want them to fill the space in the layout with the background color, as it did when I used plain QLabel widgets. What would be the right approach?
Eggert

[caduel]

if you add widgets to a vertical layout they will use the available space (horizontally).

show us some more code of what you are doing, so we do not have to guess.

[eehmke]

> if you add widgets to a vertical layout they will use the available space
> (horizontally).
That may be the problem. In the containing dialog, the widget is added to the layout:
layout_edit->addWidget (label[i], i, 0);
where label[i] is of the class described (my_label). But that widget is only a container class that contains the real widget. So what methods must I forward to the contained widget?

Here are some details:

class my_widget: public QWidget{ private:
Q_OBJECT

public:
sk_widget (QWidget *parent);
virtual QSize sizeHint () const = 0;
virtual void setAutoFillBackground (bool) = 0;

protected:
QWidget* letter;
};

my_label::my_label (const QString &text, QWidget *parent)
:my_widget (parent)
{
letter = new QLabel (text, this);
}

QSize my_label::sizeHint () const {
return ((QLabel*)letter)->sizeHint();
}

[caduel]

you need to set a layout on the containing widget (ie your 'envelope').

my_label::my_label (const QString &text, QWidget *parent)
 :my_widget (parent)
 {
  QVBoxLayout *l = new QVBoxLayout;
  letter = new QLabel(text);
  l->addWidget(this);
  setLayout(l);
 }

my_label::my_label (const QString &text, QWidget *parent)
 :my_widget (parent)
 {
  QVBoxLayout *l = new QVBoxLayout;
  letter = new QLabel(text);
  l->addWidget(this);
  setLayout(l);
 }

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HTH

[eehmke]

Yes, that was it! I only had to modify:

my_label::my_label (const QString &text, QWidget *parent)
:my_widget (parent)
{
QVBoxLayout *l = new QVBoxLayout;
letter = new QLabel(text);
l->addWidget(letter);
setLayout(l);
}

That works, only that now the labels take too much vertical space. That can't be so hard. Thanks!

[caduel]

hint: margins (in QLayout)

[eehmke]

problem solved. Thanks again