Add const/references to all signal parameters

src/widgets/fancytabwidget.h

@@ -78,8 +78,8 @@ class FancyTabWidget : public QTabWidget {
   int iconsize_largesidebar() const { return iconsize_largesidebar_; }
 
  signals:
-  void ModeChanged(FancyTabWidget::Mode mode);
-  void CurrentChanged(int);
+  void ModeChanged(const FancyTabWidget::Mode mode);
+  void CurrentChanged(const int);
 
  public slots:
   void setCurrentIndex(int idx);

src/widgets/favoritewidget.h

@@ -44,7 +44,7 @@ class FavoriteWidget : public QWidget {
   QSize sizeHint() const override;
 
  signals:
-  void FavoriteStateChanged(int, bool);
+  void FavoriteStateChanged(const int, const bool);
 
  protected:
   void paintEvent(QPaintEvent *e) override;

src/widgets/fileview.h

@@ -64,13 +64,13 @@ class FileView : public QWidget {
   void keyPressEvent(QKeyEvent *e) override;
 
  signals:
-  void PathChanged(QString path);
+  void PathChanged(const QString &path);
 
   void AddToPlaylist(QMimeData *data);
-  void CopyToCollection(QList<QUrl> urls);
-  void MoveToCollection(QList<QUrl> urls);
-  void CopyToDevice(QList<QUrl> urls);
-  void EditTags(QList<QUrl> urls);
+  void CopyToCollection(const QList<QUrl> &urls);
+  void MoveToCollection(const QList<QUrl> &urls);
+  void CopyToDevice(const QList<QUrl> &urls);
+  void EditTags(const QList<QUrl> &urls);
 
  private slots:
   void FileUp();

src/widgets/fileviewlist.h

@@ -47,11 +47,11 @@ class FileViewList : public QListView {
 
  signals:
   void AddToPlaylist(QMimeData *data);
-  void CopyToCollection(QList<QUrl> urls);
-  void MoveToCollection(QList<QUrl> urls);
-  void CopyToDevice(QList<QUrl> urls);
-  void Delete(QStringList filenames);
-  void EditTags(QList<QUrl> urls);
+  void CopyToCollection(const QList<QUrl> &urls);
+  void MoveToCollection(const QList<QUrl> &urls);
+  void CopyToDevice(const QList<QUrl> &urls);
+  void Delete(const QStringList &filenames);
+  void EditTags(const QList<QUrl> &urls);
   void Back();
   void Forward();
 

src/widgets/multiloadingindicator.h

@@ -46,7 +46,7 @@ class MultiLoadingIndicator : public QWidget {
   QSize sizeHint() const override;
 
  signals:
-  void TaskCountChange(int tasks);
+  void TaskCountChange(const int tasks);
 
  protected:
   void paintEvent(QPaintEvent*) override;

src/widgets/playingwidget.h

@@ -68,7 +68,7 @@ class PlayingWidget : public QWidget {
   bool show_above_status_bar() const { return above_statusbar_action_->isChecked(); }
 
  signals:
-  void ShowAboveStatusBarChanged(bool above);
+  void ShowAboveStatusBarChanged(const bool above);
 
  public slots:
   void Playing();

src/widgets/qsearchfield.h

@@ -36,7 +36,7 @@ class QSearchField : public QWidget {
   void setFocus();
 
  signals:
-  void textChanged(QString text);
+  void textChanged(const QString &text);
   void editingFinished();
   void returnPressed();
 

src/widgets/ratingwidget.h

@@ -55,7 +55,7 @@ class RatingWidget : public QWidget {
   void set_rating(const float rating);
 
  signals:
-  void RatingChanged(float);
+  void RatingChanged(const float rating);
 
  protected:
   void paintEvent(QPaintEvent*) override;

src/widgets/sliderslider.h

@@ -42,7 +42,7 @@ class SliderSlider : public QSlider {
 
  signals:
   // We emit this when the user has specifically changed the slider so connect to it if valueChanged() is too generic Qt also emits valueChanged(int)
-  void SliderReleased(int);
+  void SliderReleased(const int);
 
  protected:
   virtual void slideEvent(QMouseEvent*);

src/widgets/stretchheaderview.h

@@ -76,7 +76,7 @@ class StretchHeaderView : public QHeaderView {
 
  signals:
   // Emitted when the stretch mode is changed.
-  void StretchEnabledChanged(bool enabled);
+  void StretchEnabledChanged(const bool enabled);
 
  protected:
   // QWidget

src/widgets/trackslider.h

@@ -65,8 +65,8 @@ class TrackSlider : public QWidget {
   void Seek(const int gap);
 
  signals:
-  void ValueChanged(int value);
-  void ValueChangedSeconds(quint64 value);
+  void ValueChanged(const int value);
+  void ValueChangedSeconds(const quint64 value);
 
   void SeekForward();
   void SeekBackward();