QAbstractFileEngineIterator: add `bool advance()` virtual method

And remove hasNext/next() methods. This remodels QAFEI to be like
QFileSystemIterator. This better fits the logic in the newly added
QDirListing class (which uses STL-style iterators).

QFSFileEngineIterator:
Initialize the internal nativeIterator in the constructor; also replace
the advance() private method with an override for the advance() method
inherited from the base class.

QResourceFileEngineIterator:
Override currentFileInfo(), with a QResouces the QFileInfo is created
on demand if/when this method is called.

This is the backend/private API, and QDirListing is the public API that
can be used in a ranged-for to iterate over directory entries.

Change-Id: I93eb7bdd64823ac01eea2dcaaa6bcc8ad868b2c4
Reviewed-by: Assam Boudjelthia <assam.boudjelthia@qt.io>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>

1 files changed, 8 insertions, 10 deletions

diff --git a/src/corelib/doc/snippets/code/src_corelib_io_qabstractfileengine.cpp b/src/corelib/doc/snippets/code/src_corelib_io_qabstractfileengine.cpp
index 394db15f9f..557ff765a7 100644
--- a/src/corelib/doc/snippets/code/src_corelib_io_qabstractfileengine.cpp
+++ b/src/corelib/doc/snippets/code/src_corelib_io_qabstractfileengine.cpp
@@ -59,17 +59,15 @@ public:
         entries << "entry1" << "entry2" << "entry3";
     }
 
-    bool hasNext() const override
+    bool advance() override
     {
-        return index < entries.size() - 1;
-    }
-
-    QString next() override
-    {
-       if (!hasNext())
-           return QString();
-       ++index;
-       return currentFilePath();
+        if (entries.isEmpty())
+            return false;
+        if (index < entries.size() - 1) {
+            ++index;
+            return true;
+        }
+        return false;
     }
 
     QString currentFileName() override