Add const to function signature

src/base/iconprovider.cpp

@@ -29,8 +29,6 @@
 
 #include "iconprovider.h"
 
-#include <QString>
-
 IconProvider::IconProvider(QObject *parent)
     : QObject(parent)
 {
@@ -57,7 +55,7 @@ IconProvider *IconProvider::instance()
     return m_instance;
 }
 
-QString IconProvider::getIconPath(const QString &iconId)
+QString IconProvider::getIconPath(const QString &iconId) const
 {
     return ":/icons/qbt-theme/" + iconId + ".png";
 }

src/base/iconprovider.h

@@ -31,8 +31,7 @@
 #define ICONPROVIDER_H
 
 #include <QObject>
-
+#include <QString>
-class QString;
 
 class IconProvider : public QObject
 {
@@ -43,7 +42,7 @@ public:
     static void freeInstance();
     static IconProvider *instance();
 
-    virtual QString getIconPath(const QString &iconId);
+    virtual QString getIconPath(const QString &iconId) const;
 
 protected:
     explicit IconProvider(QObject *parent = nullptr);

src/gui/guiiconprovider.cpp

@@ -57,12 +57,12 @@ GuiIconProvider *GuiIconProvider::instance()
     return static_cast<GuiIconProvider *>(m_instance);
 }
 
-QIcon GuiIconProvider::getIcon(const QString &iconId)
+QIcon GuiIconProvider::getIcon(const QString &iconId) const
 {
     return getIcon(iconId, iconId);
 }
 
-QIcon GuiIconProvider::getIcon(const QString &iconId, const QString &fallback)
+QIcon GuiIconProvider::getIcon(const QString &iconId, const QString &fallback) const
 {
 #if (defined(Q_OS_UNIX) && !defined(Q_OS_MAC))
     if (m_useSystemTheme) {
@@ -78,7 +78,7 @@ QIcon GuiIconProvider::getIcon(const QString &iconId, const QString &fallback)
     return QIcon(IconProvider::getIconPath(iconId));
 }
 
-QIcon GuiIconProvider::getFlagIcon(const QString &countryIsoCode)
+QIcon GuiIconProvider::getFlagIcon(const QString &countryIsoCode) const
 {
     if (countryIsoCode.isEmpty()) return QIcon();
     return QIcon(":/icons/flags/" + countryIsoCode.toLower() + ".svg");
@@ -89,7 +89,7 @@ QIcon GuiIconProvider::getFlagIcon(const QString &countryIsoCode)
 // Otherwise, the UI looks broken if the icon is not available
 // in the correct size.
 #if (defined(Q_OS_UNIX) && !defined(Q_OS_MAC))
-QIcon GuiIconProvider::generateDifferentSizes(const QIcon &icon)
+QIcon GuiIconProvider::generateDifferentSizes(const QIcon &icon) const
 {
     // if icon is loaded from SVG format, it already contains all the required sizes and we shall not resize it
     // In that case it will be available in the following sizes:
@@ -120,7 +120,7 @@ QIcon GuiIconProvider::generateDifferentSizes(const QIcon &icon)
 }
 #endif
 
-QString GuiIconProvider::getIconPath(const QString &iconId)
+QString GuiIconProvider::getIconPath(const QString &iconId) const
 {
 #if (defined(Q_OS_UNIX) && !defined(Q_OS_MAC))
     if (m_useSystemTheme) {

src/gui/guiiconprovider.h

@@ -43,10 +43,10 @@ public:
     static void initInstance();
     static GuiIconProvider *instance();
 
-    QIcon getIcon(const QString &iconId);
+    QIcon getIcon(const QString &iconId) const;
-    QIcon getIcon(const QString &iconId, const QString &fallback);
+    QIcon getIcon(const QString &iconId, const QString &fallback) const;
-    QIcon getFlagIcon(const QString &countryIsoCode);
+    QIcon getFlagIcon(const QString &countryIsoCode) const;
-    QString getIconPath(const QString &iconId);
+    QString getIconPath(const QString &iconId) const override;
 
 private slots:
     void configure();
@@ -55,7 +55,7 @@ private:
     explicit GuiIconProvider(QObject *parent = nullptr);
     ~GuiIconProvider();
 #if (defined(Q_OS_UNIX) && !defined(Q_OS_MAC))
-    QIcon generateDifferentSizes(const QIcon &icon);
+    QIcon generateDifferentSizes(const QIcon &icon) const;
 
     bool m_useSystemTheme;
 #endif