Now my code is working fine with no error but the dialog box doesn't hold resize property... here I am giving the snapshots of what is being displayed..
Screenshot.jpg
after I click more button following is diaplyed..
Screenshot-1.jpg

and my code...
Qt Code: 
  1. #include <QtGui>
  2. #include "sortdialog.h"
  3. SortDialog::SortDialog(QWidget *parent)
  4.     : QDialog(parent)
  5. {
  6.     setupUi(this);
  7.     secondaryGroupBox->hide();
  8.     tertiaryGroupBox->hide();
  9.     formlayout->layout()->setSizeConstraint(QLayout::SetFixedSize);
  10.     setColumnRange('A', 'Z');
  11. }
  12. void SortDialog::setColumnRange(QChar first, QChar last)
  13. {
  14.     primaryColumnCombo->clear();
  15.     secondaryColumnCombo->clear();
  16.     tertiaryColumnCombo->clear();
  17.     secondaryColumnCombo->addItem(tr("None"));
  18.     tertiaryColumnCombo->addItem(tr("None"));
  19.     primaryColumnCombo->setMinimumSize(secondaryColumnCombo->sizeHint());
  20.     QChar ch = first;
  21.     while (ch <= last) {
  22.         primaryColumnCombo->addItem(QString(ch));
  23.         secondaryColumnCombo->addItem(QString(ch));
  24.         tertiaryColumnCombo->addItem(QString(ch));
  25.         ch = ch.unicode() + 1;
  26.     }
  27. }
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in above code formlayout is the grid layout of the form..
I also changed my ui file as attached...
sortdialog.ui
Plz someone tel me what should I do to have resizable property...