I can not adjust the size of a widget to your content.

Hi.

Previously I put this message in the forum for newbies, but no such luck. So I have decided to change it to this forum. Sorry for the inconvenience.

I have an MDI application (QT 4.5.3) that opens a widget that contains a table (QTableWidget) My problem is that the widget does not fit the size of the table when it opens, but if I try to increase the size of the widget, it automatically adjusts to the correct size. What am I doing wrong?

The problematic code is:

main.cpp

Code:

---

#include <QApplication>
 
#include "mainwindow.h"
 
int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
 
    MyMDI mainMDI;
    mainMDI.show();
 
    return app.exec();
}

---

mainwindow.cpp

Code:

---

#include "mainwindow.h"
 
#include <QHeaderView>
#include <QMenuBar>
 
MyTableWidget::MyTableWidget(QWidget *parent) : QWidget(parent)
{
    m_tableValues = 0;
    m_layout = 0;
}
 
void MyTableWidget::showData()
{
    QStringList headers;
    headers << tr("C1") << tr("C2") << ("C3");
 
    int maxrows = 300;
 
    m_tableValues = new QTableWidget(maxrows, 3, this);
    m_layout = new QGridLayout(this);
 
    m_tableValues->verticalHeader()->hide();
    m_tableValues->setHorizontalHeaderLabels(headers);
    m_tableValues->verticalHeader()->setUpdatesEnabled(false);
 
    for(int i = 0; i < maxrows; i++) {
        QTableWidgetItem *newItem = new QTableWidgetItem(tr("%L1").arg(1000*i+1));
        newItem->setTextColor(Qt::black);
        newItem->setTextAlignment(Qt::AlignRight | Qt::AlignVCenter);
        m_tableValues->setItem(i, i % 3, newItem);
    }
 
    m_tableValues->resizeColumnsToContents();
    m_tableValues->resizeRowsToContents();
 
    m_tableValues->setMinimumSize(m_tableValues->minimumSizeHint());
 
    m_tableValues->verticalHeader()->setUpdatesEnabled(true);
 
    m_layout->addWidget(m_tableValues);
}
 
QSize MyTableWidget::minimumSizeHint() const
{
    QSize size;
 
    if(!m_tableValues) {
        QTableWidget aux;
        size = aux.minimumSizeHint();
        return size;
    }
 
    int width = 0;
    for(int c = 0; c < m_tableValues->columnCount(); c++) {
        width += m_tableValues->columnWidth(c);
    }
 
    size.setWidth(width+50);
    size.setHeight(200);
 
    return size;
}
 
QSize MyTableWidget::sizeHint() const
{
    return minimumSizeHint();
}
 
/* -------------------------------------------------- */
/* -------------------------------------------------- */
/* -------------------------------------------------- */
 
MyMdiWindow::MyMdiWindow(QWidget *parent) : QWidget(parent)
{
    m_layout = new QVBoxLayout(this);
    m_table = new MyTableWidget(this);
    m_layout->addWidget(m_table);
    setLayout(m_layout);
}
 
void MyMdiWindow::showMyTableWidget()
{
    m_table->showData();
    m_table->setMinimumSize(m_table->sizeHint());
}
 
/* -------------------------------------------------- */
/* -------------------------------------------------- */
/* -------------------------------------------------- */
 
MyMDI::MyMDI()
{
    m_mdiArea = new QMdiArea;
    m_mdiArea->setHorizontalScrollBarPolicy(Qt::ScrollBarAsNeeded);
    m_mdiArea->setVerticalScrollBarPolicy(Qt::ScrollBarAsNeeded);
    setCentralWidget(m_mdiArea);
 
    m_openAct = new QAction(tr("Open"), this);
    connect(m_openAct, SIGNAL(triggered()),this, SLOT(open()));
 
    m_Menu = menuBar()->addMenu(tr("&Menu"));
    m_Menu->addAction(m_openAct);
}
 
void MyMDI::open()
{
    MyMdiWindow* mdiWindow = new MyMdiWindow(this);
    m_mdiArea->addSubWindow(mdiWindow);
    mdiWindow->showMyTableWidget();
    mdiWindow->show();
}

---

mainwindow.h

Code:

---

#ifndef MAINWINDOW_H
#define MAINWINDOW_H
 
#include <QMainWindow>
#include <QMdiArea>
#include <QAction>
#include <QMenu>
#include <QWidget>
#include <QTableWidget>
#include <QGridLayout>
 
class MyTableWidget : public QWidget
{
    Q_OBJECT
 
protected:
    QTableWidget* m_tableValues;
    QGridLayout* m_layout;
 
public:
    MyTableWidget(QWidget* parent = 0);
    void showData();
 
    QSize minimumSizeHint() const;
    QSize sizeHint() const;
};
 
/* -------------------------------------------------- */
/* -------------------------------------------------- */
/* -------------------------------------------------- */
 
class MyMdiWindow : public QWidget
{
    Q_OBJECT
 
protected:
    MyTableWidget* m_table;
    QVBoxLayout* m_layout;
 
public:
    MyMdiWindow(QWidget *parent = 0);
    void showMyTableWidget();
 
};
 
/* -------------------------------------------------- */
/* -------------------------------------------------- */
/* -------------------------------------------------- */
 
class MyMDI : public QMainWindow
{
    Q_OBJECT
 
public:
    MyMDI();
 
private slots:
    void open();
 
private:
    QMdiArea *m_mdiArea;
 
    QMenu *m_Menu;
    QAction *m_openAct;
    QAction *m_exitAct;
 
};
 
#endif // MAINWINDOW_H

---

Thanks in advance.

Hello again.

Seeing that there are no answers, I change the question. If at the time of creating a widget is not yet that big are the widgets that make up the form, how I can adjust the size of the widget to your content? The idea is to show a table (QTableWidget) with data loaded from a file and the file is selected from a QFileDialog. Until the file is not loaded, I do not know the number of columns that exist. How I can adjust the width of the widget that contains the QTableWidget (and other widgets) to the width of QTableWidget?

Thanks in advance.

What was wrong with the assistance the first time you asked this question?
http://www.qtcentre.org/threads/2939...ht=#post138094


As for the second question. You'd have to calculate the width that you want the QTableWidget to be and have a look at QWidget::setMinimumSize() and the related QWidget::minimumSizeHint()

Sorry. At first I put the question in the newbie forum, but after I changed the question to the programming forum. I wanted to close the thread or delete the message from the newbie forum, but could not. Thanks for the reply and sorry.