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  *                                                                         *
   6  *   This program is free software; you can redistribute it and/or modify  *
   7  *   it under the terms of the GNU General Public License as published by  *
   8  *   the Free Software Foundation; either version 2 of the License, or     *
   9  *   (at your option) any later version.                                   *
  10  *                                                                         *
  11  *   This program is distributed in the hope that it will be useful,       *
  12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  14  *   GNU General Public License for more details.                          *
  15  *                                                                         *
  16  *   You should have received a copy of the GNU General Public License     *
  17  *   along with this program; if not, write to the                         *
  18  *   Free Software Foundation, Inc.,                                       *
  19  *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA            *
  20  ***************************************************************************/
  21
  22 #include "kitemlistkeyboardsearchmanager.h"
  23
  24 KItemListKeyboardSearchManager::KItemListKeyboardSearchManager(QObject* parent) :
  25     QObject(parent),
  26     m_isSearchRestarted(false),
  27     m_timeout(1000)
  28 {
  29     m_keyboardInputTime.invalidate();
  30 }
  31
  32 KItemListKeyboardSearchManager::~KItemListKeyboardSearchManager()
  33 {
  34 }
  35
  36 bool KItemListKeyboardSearchManager::shouldClearSearchIfInputTimeReached()
  37 {
  38     const bool keyboardTimeWasValid = m_keyboardInputTime.isValid();
  39     const qint64 keyboardInputTimeElapsed = m_keyboardInputTime.restart();
  40     return (keyboardInputTimeElapsed > m_timeout) || !keyboardTimeWasValid;
  41 }
  42
  43 void KItemListKeyboardSearchManager::addKeys(const QString& keys)
  44 {
  45     if (shouldClearSearchIfInputTimeReached()) {
  46         m_searchedString.clear();
  47     }
  48
  49     const bool newSearch = m_searchedString.isEmpty();
  50
  51     // Do not start a new search if the user pressed Space. Only add
  52     // it to the search string if a search is in progress already.
  53     if (newSearch && keys == QLatin1Char(' ')) {
  54         return;
  55     }
  56
  57     if (!keys.isEmpty()) {
  58         m_searchedString.append(keys);
  59
  60         // Special case:
  61         // If the same key is pressed repeatedly, the next item matching that key should be highlighted
  62         const QChar firstKey = m_searchedString.length() > 0 ? m_searchedString.at(0) : QChar();
  63         const bool sameKey = m_searchedString.length() > 1 && m_searchedString.count(firstKey) == m_searchedString.length();
  64
  65         // Searching for a matching item should start from the next item if either
  66         // 1. a new search is started and a search has not been restarted or
  67         // 2. a 'repeated key' search is done.
  68         const bool searchFromNextItem = (!m_isSearchRestarted && newSearch) || sameKey;
  69
  70         // to remember not to searchFromNextItem if selection was deselected
  71         // loosing keyboard search context basically
  72         m_isSearchRestarted = false;
  73
  74         emit changeCurrentItem(sameKey ? firstKey : m_searchedString, searchFromNextItem);
  75     }
  76     m_keyboardInputTime.start();
  77 }
  78
  79 void KItemListKeyboardSearchManager::setTimeout(qint64 milliseconds)
  80 {
  81     m_timeout = milliseconds;
  82 }
  83
  84 qint64 KItemListKeyboardSearchManager::timeout() const
  85 {
  86     return m_timeout;
  87 }
  88
  89 void KItemListKeyboardSearchManager::cancelSearch()
  90 {
  91     m_isSearchRestarted = true;
  92     m_searchedString.clear();
  93 }
  94
  95 void KItemListKeyboardSearchManager::slotCurrentChanged(int current, int previous)
  96 {
  97     Q_UNUSED(previous)
  98
  99     if (current < 0) {
 100         // The current item has been removed. We should cancel the search.
 101         cancelSearch();
 102     }
 103 }
 104
 105 void KItemListKeyboardSearchManager::slotSelectionChanged(const KItemSet& current, const KItemSet& previous)
 106 {
 107     if (!previous.isEmpty() && current.isEmpty() && previous.count() > 0 && current.count() == 0) {
 108         // The selection has been emptied. We should cancel the search.
 109         cancelSearch();
 110     }
 111 }