From 3f0075f61609791a368e35be6b1862b6145a6b1e Mon Sep 17 00:00:00 2001
From: Uwe Rathmann <Uwe.Rathmann@tigertal.de>
Date: Sun, 21 Jan 2018 14:10:12 +0100
Subject: [PATCH] improving focus handling after closing a popup

---
 src/controls/QskControl.cpp |   8 +++
 src/controls/QskControl.h   |   1 +
 src/controls/QskPopup.cpp   | 101 ++++++++++--------------------------
 src/controls/QskPopup.h     |   2 +
 4 files changed, 37 insertions(+), 75 deletions(-)

diff --git a/src/controls/QskControl.cpp b/src/controls/QskControl.cpp
index 437bac8c..9cbc4171 100644
--- a/src/controls/QskControl.cpp
+++ b/src/controls/QskControl.cpp
@@ -114,6 +114,14 @@ QQuickItem* qskNearestFocusScope( const QQuickItem* item )
     return nullptr;
 }
 
+QList<QQuickItem *> qskPaintOrderChildItems( const QQuickItem* item )
+{
+    if ( item )
+        return QQuickItemPrivate::get( item )->paintOrderChildItems();
+
+    return QList<QQuickItem *>();
+}
+
 const QSGNode* qskItemNode( const QQuickItem* item )
 {
     if ( item == nullptr )
diff --git a/src/controls/QskControl.h b/src/controls/QskControl.h
index 681c9177..016e12c1 100644
--- a/src/controls/QskControl.h
+++ b/src/controls/QskControl.h
@@ -247,6 +247,7 @@ QSK_EXPORT bool qskIsTabFence( const QQuickItem* );
 QSK_EXPORT bool qskIsShortcutScope( const QQuickItem* );
 
 QSK_EXPORT QQuickItem* qskNearestFocusScope( const QQuickItem* );
+QSK_EXPORT QList<QQuickItem *> qskPaintOrderChildItems( const QQuickItem* );
 
 QSK_EXPORT const QSGNode* qskItemNode( const QQuickItem* );
 QSK_EXPORT const QSGNode* qskPaintNode( const QQuickItem* );
diff --git a/src/controls/QskPopup.cpp b/src/controls/QskPopup.cpp
index f203517a..ce15e07e 100644
--- a/src/controls/QskPopup.cpp
+++ b/src/controls/QskPopup.cpp
@@ -6,8 +6,6 @@
 #include "QskPopup.h"
 #include "QskAspect.h"
 #include <QQuickWindow>
-#include <QGuiApplication>
-#include <QStyleHints>
 #include <QtMath>
 
 QSK_QT_PRIVATE_BEGIN
@@ -17,7 +15,7 @@ QSK_QT_PRIVATE_END
 
 QSK_SUBCONTROL( QskPopup, Overlay )
 
-static void qskSetFocusInScope( QQuickItem* item, bool on )
+static void qskSetFocus( QQuickItem* item, bool on )
 {
     if ( item->window() == nullptr )
         return;
@@ -39,71 +37,6 @@ static void qskSetFocusInScope( QQuickItem* item, bool on )
     }
 }
 
-static QQuickItem* qskNextFocusItem( const QskPopup* popup )
-{
-    if ( popup == nullptr || popup->parentItem() == nullptr )
-        return nullptr;
-
-    const auto children = popup->parentItem()->childItems();
-    if ( children.count() <= 1 )
-        return nullptr;
-
-    QskPopup* modalPopup = nullptr;
-
-    for ( auto child : children )
-    {
-        if ( ( child != popup ) && child->isVisible() )
-        {
-            if ( auto otherPopup = qobject_cast< QskPopup* >( child ) )
-            {
-                if ( !otherPopup->isModal() || ( modalPopup != nullptr ) )
-                {
-                    /*
-                        We can't decide, wether to give the focus to
-                        one of the popups or the top level item
-                     */
-                    return nullptr;
-                }
-
-                modalPopup = otherPopup;
-            }
-        }
-    }
-
-    if ( modalPopup )
-    {
-        // Exactly one popup, that is modal.
-        return modalPopup;
-    }
-
-    const auto tabFocusBehavior = QGuiApplication::styleHints()->tabFocusBehavior();
-
-    int i = 0;
-    while( children[i] != popup )
-        i++;
-
-    for ( int j = i - 1; j != i; j-- )
-    {
-        auto item = children[j];
-        if ( item->isEnabled() && item->isVisible() )
-        {
-            if ( item->activeFocusOnTab() )
-            {
-                if ( ( tabFocusBehavior == Qt::TabFocusAllControls ) ||
-                    QQuickItemPrivate::canAcceptTabFocus( item ) )
-                {
-                    return item;
-                }
-            }
-        }
-
-        if ( j == 0 )
-            j = children.count();
-    }
-
-    return nullptr;
-}
-
 namespace
 {
     class InputGrabber final : public QQuickItem
@@ -339,11 +272,11 @@ void QskPopup::grabFocus( bool on )
 
     if ( on )
     {
-        qskSetFocusInScope( this, true );
+        qskSetFocus( this, true );
     }
     else
     {
-        QQuickItem* focusItem = nullptr;
+        QQuickItem* successor = nullptr;
 
         if ( m_data->handoverFocus )
         {
@@ -352,13 +285,14 @@ void QskPopup::grabFocus( bool on )
                 when the active focus gets lost. For the situation of
                 a popup being closed we try to do it.
              */
-            focusItem = qskNextFocusItem( this );
+            successor = focusSuccessor();
         }
 
-        if ( focusItem )
-            qskSetFocusInScope( focusItem, true );
-        else
-            qskSetFocusInScope( this, false );
+        if ( successor )
+            qskSetFocus( successor, true );
+
+        if ( hasFocus() )
+            qskSetFocus( this, false );
     }
 }
 
@@ -388,6 +322,23 @@ bool QskPopup::event( QEvent* event )
     return ok;
 }
 
+QQuickItem* QskPopup::focusSuccessor() const
+{
+    if ( const auto scope = qskNearestFocusScope( this ) )
+    {
+        const auto children = qskPaintOrderChildItems( scope );
+        for ( auto it = children.crbegin(); it != children.crend(); ++it)
+        {
+            auto child = *it;
+
+            if ( child != this && child->isFocusScope() )
+                return child;
+        }
+    }
+
+    return nullptr;
+}
+
 void QskPopup::updateLayout()
 {
     if ( !m_data->isOpen )
diff --git a/src/controls/QskPopup.h b/src/controls/QskPopup.h
index 63bb47e7..41f98fb3 100644
--- a/src/controls/QskPopup.h
+++ b/src/controls/QskPopup.h
@@ -43,6 +43,8 @@ protected:
     virtual void itemChange( QQuickItem::ItemChange,
         const QQuickItem::ItemChangeData& ) override;
 
+    virtual QQuickItem* focusSuccessor() const;
+
     void grabFocus( bool );
 
 private: