File indexing completed on 2025-01-05 04:55:03

 /*
     Copyright (c) 2021 Christian Mollekopf <christian@mkpf.ch>
 
     This library is free software; you can redistribute it and/or modify it
     under the terms of the GNU Library General Public License as published by
     the Free Software Foundation; either version 2 of the License, or (at your
     option) any later version.
 
     This library 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 Library General Public
     License for more details.
 
     You should have received a copy of the GNU Library General Public License
     along with this library; see the file COPYING.LIB.  If not, write to the
     Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
     02110-1301, USA.
 */
 #pragma once
 
 #include <QTimer>
 #include <functional>
 
 /**
  * A signal throttler/debouncer
  *
  * The callback is initially slightly delayed, to debounce multiple calls in quick succession.
  * The delay used for this is small to provide responsiveness. Successive calls are then batched into a single callback after  mInterval ms.
  */
 class Debouncer {
     public:
         Debouncer(int interval, std::function<void()> callback, QObject *guard)
             :mInterval{interval},
             mCallback{callback}
         {
             mRefreshTimer.setSingleShot(true);
             QObject::connect(&mRefreshTimer, &QTimer::timeout, guard, [this] {
                 //Avoid calling after the timeout if there was no trigger inbetween
                 if (!mCalledAlready) {
                     mCallback();
                 }
             });
 
             mDelayTimer.setSingleShot(true);
             QObject::connect(&mDelayTimer, &QTimer::timeout, guard, [this] {
                 mCalledAlready = true;
                 mCallback();
             });
         }
 
         void trigger() {
             mCalledAlready = false;
             if (!mRefreshTimer.isActive()) {
                 mRefreshTimer.start(mInterval);
                 mDelayTimer.start(30);
             }
         }
 
     private:
         int mInterval;
         bool mCalledAlready{false};
         QTimer mRefreshTimer;
         QTimer mDelayTimer;
         std::function<void()> mCallback;
 };