src/kitemviews/private/kitemlistkeyboardsearchmanager.cpp

   1 /***************************************************************************
   2  * Copyright (C) 2011 by Tirtha Chatterjee <tirtha.p.chatterjee@gmail.com> *
   3  *                                                                         *
   4  *   Based on the Itemviews NG project from Trolltech Labs:                *
   5  *   http://qt.gitorious.org/qt-labs/itemviews-ng                          *
   6  *                                                                         *
   7  *   This program is free software; you can redistribute it and/or modify  *
   8  *   it under the terms of the GNU General Public License as published by  *
   9  *   the Free Software Foundation; either version 2 of the License, or     *
  10  *   (at your option) any later version.                                   *
  11  *                                                                         *
  12  *   This program is distributed in the hope that it will be useful,       *
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  15  *   GNU General Public License for more details.                          *
  16  *                                                                         *
  17  *   You should have received a copy of the GNU General Public License     *
  18  *   along with this program; if not, write to the                         *
  19  *   Free Software Foundation, Inc.,                                       *
  20  *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA            *
  21  ***************************************************************************/
  22
  23 #include "kitemlistkeyboardsearchmanager.h"
  24
  25 #include <QApplication>
  26 #include <QElapsedTimer>
  27
  28 KItemListKeyboardSearchManager::KItemListKeyboardSearchManager(QObject* parent) :
  29     QObject(parent),
  30     m_timeout(1000)
  31 {
  32     m_keyboardInputTime.invalidate();
  33 }
  34
  35 KItemListKeyboardSearchManager::~KItemListKeyboardSearchManager()
  36 {
  37 }
  38
  39 void KItemListKeyboardSearchManager::addKeys(const QString& keys)
  40 {
  41     const bool keyboardTimeWasValid = m_keyboardInputTime.isValid();
  42     const qint64 keyboardInputTimeElapsed = m_keyboardInputTime.restart();
  43     if (keyboardInputTimeElapsed > m_timeout || !keyboardTimeWasValid) {
  44         m_searchedString.clear();
  45     }
  46
  47     const bool newSearch = m_searchedString.isEmpty();
  48
  49     // Do not start a new search if the user pressed Space. Only add
  50     // it to the search string if a search is in progress already.
  51     if (newSearch && keys == QLatin1String(" ")) {
  52         return;
  53     }
  54
  55     if (!keys.isEmpty()) {
  56         m_searchedString.append(keys);
  57
  58         // Special case:
  59         // If the same key is pressed repeatedly, the next item matching that key should be highlighted
  60         const QChar firstKey = m_searchedString.length() > 0 ? m_searchedString.at(0) : QChar();
  61         const bool sameKey = m_searchedString.length() > 1 && m_searchedString.count(firstKey) == m_searchedString.length();
  62
  63         // Searching for a matching item should start from the next item if either
  64         // 1. a new search is started, or
  65         // 2. a 'repeated key' search is done.
  66         const bool searchFromNextItem = newSearch || sameKey;
  67
  68         emit changeCurrentItem(sameKey ? firstKey : m_searchedString, searchFromNextItem);
  69     }
  70     m_keyboardInputTime.start();
  71 }
  72
  73 void KItemListKeyboardSearchManager::setTimeout(qint64 milliseconds)
  74 {
  75     m_timeout = milliseconds;
  76 }
  77
  78 qint64 KItemListKeyboardSearchManager::timeout() const
  79 {
  80     return m_timeout;
  81 }
  82
  83 void KItemListKeyboardSearchManager::cancelSearch()
  84 {
  85     m_searchedString.clear();
  86 }
  87
  88 void KItemListKeyboardSearchManager::slotCurrentChanged(int current, int previous)
  89 {
  90     Q_UNUSED(previous);
  91
  92     if (current < 0) {
  93         // The current item has been removed. We should cancel the search.
  94         cancelSearch();
  95     }
  96 }