Fix item highlighting through DBus

Before this commit, even items that are distant children of
currently open views were considered selectable. This lead to the
bug that items meant to be highlighted through DBus would not be
highlighted if any ancestor of the item was open in any view.

This was fixed by only considering items in view if they can be
seen by scrolling. Main difficulty here was to make this also work
for the details view mode which allows expanding.

To implement this cleanly, some refactoring seemed necessary
because the logic to determine if an item is already in view
was previously intertwined with the logic to identify already open
directories.

This commit also contains the following refactorings aiming to
make the code more readable:
- A magic value (-1) is replaced using std::optional.
- A boolean trap is removed.
- A QPair is replaced by a struct with named variables.
- More and improved documentation

1 files changed, 3 insertions, 5 deletions

diff --git a/src/dolphinmainwindow.h b/src/dolphinmainwindow.h
index e7355e3ed..6f922168c 100644
--- a/src/dolphinmainwindow.h
+++ b/src/dolphinmainwindow.h
@@ -153,13 +153,11 @@ public Q_SLOTS:
     bool isUrlOpen(const QString &url);
 
     /**
-     * Determines if a URL or it's parent is open in any tab.
+     * @return Whether the item with @p url can be found in any view only by switching
+     * between already open tabs and scrolling in their primary or secondary view.
      * @note Use of QString instead of QUrl is required to be callable via DBus.
-     *
-     * @param url URL to look for
-     * @returns true if url or it's parent is currently open in a tab, false otherwise.
      */
-    bool isUrlOrParentOpen(const QString &url);
+    bool isItemVisibleInAnyView(const QString &urlOfItem);
 
 
     /**