Bug #63962 Dynamically scan the config directory for icon themes

The hard-coded icon themes have been replaced by a dynamic list
which is filled by scanning the config directory

Conflicts:
include/vcl/settings.hxx
vcl/source/app/settings.cxx
vcl/source/window/window.cxx

Change-Id: Ie3680ffe27d06e375acf22753e036cb6ddabc4ed
Reviewed-on: https://gerrit.libreoffice.org/7935
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>

1 files changed, 101 insertions, 0 deletions

diff --git a/include/vcl/IconThemeSelector.hxx b/include/vcl/IconThemeSelector.hxx
new file mode 100644
index 000000000000..35bde9e510f6
--- /dev/null
+++ b/include/vcl/IconThemeSelector.hxx
@@ -0,0 +1,101 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+#ifndef VCL_ICONTHEMESELECTOR_HXX_
+#define VCL_ICONTHEMESELECTOR_HXX_
+
+#include <rtl/ustring.hxx>
+
+#include <vcl/dllapi.h>
+
+#include <vector>
+
+// forward declaration of unit test class. Required for friend relationship.
+class IconThemeSelectorTest;
+
+namespace vcl {
+struct IconThemeInfo;
+
+/** This class helps to choose an icon theme from a list of installed themes.
+ *
+ * The following factors influence the selection:
+ * -# When high contrast mode is enabled, the high contrast icon theme is selected (if it is installed).
+ * -# When a preferred theme has been set (e.g., in the gnome desktop settings), that theme is selected.
+ */
+class SAL_DLLPUBLIC_EXPORT IconThemeSelector {
+public:
+    IconThemeSelector();
+
+    /** Select an icon theme from the list of installed themes.
+     *
+     * If high contrast mode has been enabled, the highcontrast theme will be selected (if it is available).
+     *
+     * @pre
+     * @p installedThemes must not be empty
+     */
+    OUString
+    SelectIconTheme(
+            const std::vector<IconThemeInfo>& installedThemes,
+            const OUString& theme
+            ) const;
+
+    /** Select the standard icon theme for a desktop environment from a list of installed themes.
+     *
+     * If a preferred theme has been set, this one will take precedence.
+     *
+     * The same logic as in SelectIconTheme() will apply.
+     *
+     * @pre
+     * @p installedThemes must not be empty
+     */
+    OUString
+    SelectIconThemeForDesktopEnvironment(
+            const std::vector<IconThemeInfo>& installedThemes,
+            const OUString& desktopEnvironment) const;
+
+    void
+    SetUseHighContrastTheme(bool);
+
+    void
+    SetPreferredIconTheme(const OUString&);
+
+    bool
+    operator==(const vcl::IconThemeSelector&) const;
+
+    bool
+    operator!=(const vcl::IconThemeSelector&) const;
+
+private:
+    /** Return the first element of the themes, or the fallback if the vector is empty */
+    static OUString
+    ReturnFallback(const std::vector<IconThemeInfo>& installedThemes);
+
+    /** The name of the icon theme to use for high contrast mode */
+    static const OUString
+    HIGH_CONTRAST_ICON_THEME_ID;
+
+    /** The name of the icon theme which is used as fallback */
+    static const OUString
+    FALLBACK_ICON_THEME_ID;
+
+
+    static OUString
+    GetIconThemeForDesktopEnvironment(const OUString& desktopEnvironment);
+
+    OUString mPreferredIconTheme;
+    bool mUseHighContrastTheme;
+
+    friend class ::IconThemeSelectorTest;
+};
+
+} /* namespace vcl */
+
+#endif /* VCL_ICONTHEMESELECTOR_HXX_ */
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */