QGIS API Documentation  3.19.0-Master (c9e5875a2b)
qgsfeedback.h
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1 /***************************************************************************
2  qgsfeedback.h
3  --------------------------------------
4  Date : July 2016
5  Copyright : (C) 2016 by Martin Dobias
6  Email : wonder dot sk at gmail dot com
7  ***************************************************************************
8  * *
9  * This program is free software; you can redistribute it and/or modify *
10  * it under the terms of the GNU General Public License as published by *
11  * the Free Software Foundation; either version 2 of the License, or *
12  * (at your option) any later version. *
13  * *
14  ***************************************************************************/
15 
16 #ifndef QGSFEEDBACK_H
17 #define QGSFEEDBACK_H
18 
19 #include <QObject>
20 
21 #include "qgis_core.h"
22 #include "qgis_sip.h"
23 
44 class CORE_EXPORT QgsFeedback : public QObject
45 {
46  Q_OBJECT
47  public:
49  QgsFeedback( QObject *parent SIP_TRANSFERTHIS = nullptr )
50  : QObject( parent )
51  {}
52 
54  bool isCanceled() const { return mCanceled; }
55 
63  void setProgress( double progress )
64  {
65  // avoid flooding with too many events
66  if ( static_cast< int >( mProgress * 10 ) != static_cast< int >( progress * 10 ) )
67  emit progressChanged( progress );
68 
69  mProgress = progress;
70  }
71 
80  double progress() const { return mProgress; }
81 
82  public slots:
83 
85  void cancel()
86  {
87  if ( mCanceled )
88  return; // only emit the signal once
89  mCanceled = true;
90  emit canceled();
91  }
92 
93  signals:
95  void canceled();
96 
105  void progressChanged( double progress );
106 
107  private:
109  bool mCanceled = false;
110 
111  double mProgress = 0.0;
112 };
113 
114 #endif // QGSFEEDBACK_H
Base class for feedback objects to be used for cancellation of something running in a worker thread.
Definition: qgsfeedback.h:45
bool isCanceled() const
Tells whether the operation has been canceled already.
Definition: qgsfeedback.h:54
void progressChanged(double progress)
Emitted when the feedback object reports a progress change.
void canceled()
Internal routines can connect to this signal if they use event loop.
QgsFeedback(QObject *parent=nullptr)
Construct a feedback object.
Definition: qgsfeedback.h:49
void cancel()
Tells the internal routines that the current operation should be canceled. This should be run by the ...
Definition: qgsfeedback.h:85
void setProgress(double progress)
Sets the current progress for the feedback object.
Definition: qgsfeedback.h:63
double progress() const
Returns the current progress reported by the feedback object.
Definition: qgsfeedback.h:80
#define SIP_TRANSFERTHIS
Definition: qgis_sip.h:53