CODEWITHSUNDEEP
c++qtuser-interfaceqtablewidget
Scott
Scott

Reputation: 43

QTableWidget: Prioritize horizontal space for a specific column

I have a QTableWidget that has a column (#3) that needs more space than others. I want to resize all columns to their contents, and give priority to column #3. If column #3 pushes the table's width past what's available, I want column #3 to be truncated with '...' without a horizontal scrollBar.

The screenshot below is the simplest example of the behavior I'm chasing, but I've had to manually adjust the column widths. I want the table to do this automatically.

enter image description here

The following code shows examples of what I've tried on QTableWidget, but none have worked. I've provided inline comments on why the following methods do not work:

table->horizontalHeader()->setStretchLastSection(true);
table->resizeColumnsToContents();

Thank you to anyone who volunteers your time to help me with this.

#include <QApplication>
#include <QTableWidget>
#include <QStringList>
#include <QRect>
#include <QLayout>
#include <QDialog>
#include <QHeaderView>

#include <iostream>

int main( int argc, char* argv[] )
{
    QApplication a(argc, argv);

    QDialog* d = new QDialog();
    d->setLayout( new QVBoxLayout() );

    QTableWidget* table = new QTableWidget(1,4);
    QStringList headers = {"1", "2", "3", "4"};
    table->setHorizontalHeaderLabels(headers);

    table->setItem(0, 0, new QTableWidgetItem("1"));
    table->setItem(0, 1, new QTableWidgetItem("22222"));
    table->setItem(0, 2, new QTableWidgetItem("33333333333333333333333333333"));
    table->setItem(0, 3, new QTableWidgetItem("4"));

    // Do nothing
    //
    //   The table exceeds the dimensions of the dialog,
    //   and we get a horizontal scrollbar

    // This also results in a horizontal scrollbar
    //
    //  table->horizontalHeader()->setStretchLastSection(true);

    // Resizing the columns introduces a horizontal scrollbar, and
    // prevents the user from from changing column width
    //
    //  table->resizeColumnsToContents();

    // The table fits, but all columns are equally spaced.
    // (We want column 3 to take up as much space as possible)
    //
    // table->horizontalHeader()->setSectionResizeMode(QHeaderView::Stretch);

    // Columns are resized to their contents,
    // but column 3 is not truncated and we get a horizontal scrollBar
    //
    //  table->horizontalHeader()->setSectionResizeMode(QHeaderView::ResizeToContents);

    d->layout()->addWidget( table );
    d->show();
    return a.exec();
}

Upvotes: 0

Views: 367

Answers (1)

AnthonySimons
AnthonySimons

Reputation: 110

This should work, try it out

#include <QApplication>
#include <QTableWidget>
#include <QStringList>
#include <QRect>
#include <QLayout>
#include <QDialog>
#include <QHeaderView>
#include <QScrollBar>

#include <iostream>

int main( int argc, char* argv[] )
{
QApplication a(argc, argv);

QDialog* d = new QDialog();
d->setLayout( new QVBoxLayout() );

QTableWidget* table = new QTableWidget(1,4);
QStringList headers = {"1", "2", "3", "4"};
table->setHorizontalHeaderLabels(headers);

table->setItem(0, 0, new QTableWidgetItem("1"));
table->setItem(0, 1, new QTableWidgetItem("22222"));
table->setItem(0, 2, new QTableWidgetItem("33333333333333333333333333333"));
table->setItem(0, 3, new QTableWidgetItem("4"));

// Do nothing
//
//   The table exceeds the dimensions of the dialog,
//   and we get a horizontal scrollbar

// This also results in a horizontal scrollbar
//
//  table->horizontalHeader()->setStretchLastSection(true);

// Resizing the columns introduces a horizontal scrollbar, and
// prevents the user from changing column width
//

 //resize table
  d->layout()->addWidget( table );
  d->show();

  table->resizeColumnsToContents();

  int tableWidth = table->width();
  int columsWidth = 0;
  int maxColumnWidth = 0;
  int maxColumnIndex = 0;
  int w = 0;

  for(int n = 0; n < table->columnCount(); n++)
  {
      w = table->columnWidth(n);
      columsWidth += w;
      if(w > maxColumnWidth)
      {
          maxColumnWidth = w;
          maxColumnIndex = n;
      }
  }

  if(columsWidth > tableWidth)
  {
      int delta = columsWidth - tableWidth + table->horizontalScrollBar()->height();
      maxColumnWidth -= delta;
      if(maxColumnWidth < 0)
          maxColumnWidth = 0;
      table->setColumnWidth(maxColumnIndex, maxColumnWidth);
  }

// This table fits, but all the columns are equally spaced.
// (We want column 3 to take up as much space as possible)
//
// table->horizontalHeader()->setSectionResizeMode(QHeaderView::Stretch);

// Columns are resized to their contents,
// but column 3 is not truncated and we get a horizontal scrollBar
//
//  table->horizontalHeader()->setSectionResizeMode(QHeaderView::ResizeToContents);

return a.exec();

}

Get back to me if you have any problems with this code.

Upvotes: 1

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