QTfrontend/ui/widget/HistoryLineEdit.cpp
author Mitchell Kember <mk12360@gmail.com>
Fri, 30 Nov 2012 20:00:53 -0500
changeset 8149 237802cf4610
parent 6952 7f70f37bbf08
child 9080 9b42757d7e71
permissions -rw-r--r--
Google Code-in: Center help text field Modifies the grid layout slightly so that the help text which appears when hovering over certain elements is centered with respect to the window, even when there are more buttons on one side. https://google-melange.appspot.com/gci/task/view/google/gci2012/7968226

/*
 * Hedgewars, a free turn based strategy game
 * Copyright (c) 2006-2007 Igor Ulyanov <iulyanov@gmail.com>
 * Copyright (c) 2004-2012 Andrey Korotaev <unC0Rr@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
 */

/**
 * @file
 * @brief HistoryLineEdit class implementation
 */

#include <QStringList>

#include "HistoryLineEdit.h"

HistoryLineEdit::HistoryLineEdit(QWidget * parent, int maxHistorySize)
    : QLineEdit(parent)
{
    m_curHistEntryIdx = 0;
    m_maxHistorySize = maxHistorySize;
    m_history = new QStringList();
}


HistoryLineEdit::~HistoryLineEdit()
{
    delete m_history;
}


void HistoryLineEdit::rememberCurrentText()
{
    QString newEntry = text();

    // don't store whitespace-only/empty text
    if (newEntry.trimmed().isEmpty())
        return;

    m_history->removeOne(newEntry); // no duplicates please
    m_history->append(newEntry);

    // do not keep more entries than allowed
    if (m_history->size() > m_maxHistorySize)
        m_history->removeFirst();

    // we're looking at the latest entry
    m_curHistEntryIdx = m_history->size() - 1;
}


void HistoryLineEdit::clear()
{
    QLineEdit::clear();
    m_curHistEntryIdx = m_history->size();
}


void HistoryLineEdit::reset()
{
    // forget history
    m_history->clear();
    m_curHistEntryIdx = 0;
}


void HistoryLineEdit::navigateHistory(bool isGoingUp)
{
    // save possible changes to new entry
    if ((m_curHistEntryIdx >= m_history->size() ||
            (text() != m_history->at(m_curHistEntryIdx))))
    {
        rememberCurrentText();
    }

    if (isGoingUp)
        m_curHistEntryIdx--;
    else
        m_curHistEntryIdx++;

    // if Idx higher than valid range
    if (m_curHistEntryIdx >= m_history->size())
    {
        QLineEdit::clear();
        m_curHistEntryIdx = m_history->size();
    }
    // if Idx in valid range
    else if (m_curHistEntryIdx >= 0)
    {
        setText(m_history->at(m_curHistEntryIdx));
    }
    // if Idx below 0
    else
        m_curHistEntryIdx = 0;

}


void HistoryLineEdit::keyPressEvent(QKeyEvent * event)
{
    int key = event->key(); // retrieve pressed key

    // navigate history with arrow keys
    if (event->modifiers() == Qt::NoModifier)
        switch (key)
        {
            case Qt::Key_Escape:
                clear();
                event->accept();
                break;

            case Qt::Key_Up:
                navigateHistory(true);
                event->accept();
                break;

            case Qt::Key_Down:
                navigateHistory(false);
                event->accept();
                break;

            default:
                QLineEdit::keyPressEvent(event);
                break;
        }
    // otherwise forward keys to parent
    else
        QLineEdit::keyPressEvent(event);
}