pv/globalsettings.cpp

   1 /*
   2  * This file is part of the PulseView project.
   3  *
   4  * Copyright (C) 2017 Soeren Apel <soeren@apelpie.net>
   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, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include "globalsettings.hpp"
  21
  22 using std::function;
  23 using std::map;
  24 using std::multimap;
  25
  26 namespace pv {
  27
  28 const QString GlobalSettings::Key_View_AlwaysZoomToFit = "View_AlwaysZoomToFit";
  29 const QString GlobalSettings::Key_View_ColouredBG = "View_ColouredBG";
  30 const QString GlobalSettings::Key_View_StickyScrolling = "View_StickyScrolling";
  31 const QString GlobalSettings::Key_View_ShowSamplingPoints = "View_ShowSamplingPoints";
  32
  33 multimap< QString, function<void(QVariant)> > GlobalSettings::callbacks_;
  34 bool GlobalSettings::tracking_ = false;
  35 map<QString, QVariant> GlobalSettings::tracked_changes_;
  36
  37 GlobalSettings::GlobalSettings() :
  38         QSettings()
  39 {
  40         beginGroup("Settings");
  41 }
  42
  43 void GlobalSettings::register_change_handler(const QString key,
  44         function<void(QVariant)> cb)
  45 {
  46         callbacks_.emplace(key, cb);
  47 }
  48
  49 void GlobalSettings::setValue(const QString &key, const QVariant &value)
  50 {
  51         // Save previous value if we're tracking changes,
  52         // not altering an already-existing saved setting
  53         if (tracking_)
  54                 tracked_changes_.emplace(key, QSettings::value(key));
  55
  56         QSettings::setValue(key, value);
  57
  58         // Call all registered callbacks for this key
  59         auto range = callbacks_.equal_range(key);
  60
  61         for (auto it = range.first; it != range.second; it++)
  62                 it->second(value);
  63 }
  64
  65 void GlobalSettings::start_tracking()
  66 {
  67         tracking_ = true;
  68         tracked_changes_.clear();
  69 }
  70
  71 void GlobalSettings::stop_tracking()
  72 {
  73         tracking_ = false;
  74         tracked_changes_.clear();
  75 }
  76
  77 void GlobalSettings::undo_tracked_changes()
  78 {
  79         tracking_ = false;
  80
  81         for (auto entry : tracked_changes_)
  82                 setValue(entry.first, entry.second);
  83
  84         tracked_changes_.clear();
  85 }
  86
  87 } // namespace pv