From 74c349e6c6354bba3c7242eb9de2b6bbeb462ecd Mon Sep 17 00:00:00 2001
From: Uwe Rathmann <Uwe.Rathmann@tigertal.de>
Date: Wed, 4 Sep 2019 08:08:13 +0200
Subject: [PATCH] blocking of LayoutRequest events to QskControlPrivate

---
 src/controls/QskControlPrivate.cpp   | 22 +++++++++++++++++-----
 src/controls/QskControlPrivate.h     |  3 +++
 src/controls/QskQuickItemPrivate.cpp | 24 +++++++-----------------
 src/controls/QskQuickItemPrivate.h   |  7 ++-----
 4 files changed, 29 insertions(+), 27 deletions(-)

diff --git a/src/controls/QskControlPrivate.cpp b/src/controls/QskControlPrivate.cpp
index 265c9278..c981e94a 100644
--- a/src/controls/QskControlPrivate.cpp
+++ b/src/controls/QskControlPrivate.cpp
@@ -44,6 +44,7 @@ QskControlPrivate::QskControlPrivate()
     , autoLayoutChildren( false )
     , focusPolicy( Qt::NoFocus )
     , isWheelEnabled( false )
+    , blockLayoutRequestEvents( true )
 {
 }
 
@@ -52,14 +53,25 @@ QskControlPrivate::~QskControlPrivate()
     delete [] explicitSizeHints;
 }
 
+void QskControlPrivate::layoutConstraintChanged()
+{
+    if ( !blockLayoutRequestEvents )
+    {
+        Inherited::layoutConstraintChanged();
+
+        /*
+            We don't send further LayoutRequest events until someone
+            actively requests a layout relevant information
+         */
+        blockLayoutRequestEvents = true;
+    }
+}
+
 void QskControlPrivate::implicitSizeChanged()
 {
-    Q_Q( QskControl );
-    if ( !q->explicitSizeHint( Qt::PreferredSize ).isValid() )
+    if ( !q_func()->explicitSizeHint( Qt::PreferredSize ).isValid() )
     {
-        // when we have no PreferredSize we fall back
-        // to the implicit size
-
+        // when we have no explit size, the implicit size matters
         layoutConstraintChanged();
     }
 }
diff --git a/src/controls/QskControlPrivate.h b/src/controls/QskControlPrivate.h
index 3da5af93..66b89f9b 100644
--- a/src/controls/QskControlPrivate.h
+++ b/src/controls/QskControlPrivate.h
@@ -35,6 +35,7 @@ class QskControlPrivate : public QskQuickItemPrivate
 
     QSizeF implicitSizeHint() const override final;
     void implicitSizeChanged() override final;
+    void layoutConstraintChanged() override final;
 
   private:
     Q_DECLARE_PUBLIC( QskControl )
@@ -51,6 +52,8 @@ class QskControlPrivate : public QskQuickItemPrivate
 
     uint focusPolicy : 4;
     bool isWheelEnabled : 1;
+
+    mutable bool blockLayoutRequestEvents : 1;
 };
 
 #endif
diff --git a/src/controls/QskQuickItemPrivate.cpp b/src/controls/QskQuickItemPrivate.cpp
index 6bae2311..cedebc49 100644
--- a/src/controls/QskQuickItemPrivate.cpp
+++ b/src/controls/QskQuickItemPrivate.cpp
@@ -26,7 +26,6 @@ QskQuickItemPrivate::QskQuickItemPrivate()
     , blockedImplicitSize( true )
     , clearPreviousNodes( false )
     , isInitiallyPainted( false )
-    , blockLayoutRequestEvents( true )
 {
     if ( controlFlags & QskQuickItem::DeferredLayout )
     {
@@ -55,8 +54,7 @@ QskQuickItemPrivate::~QskQuickItemPrivate()
 
 void QskQuickItemPrivate::mirrorChange()
 {
-    Q_Q( QskQuickItem );
-    qskSendEventTo( q, QEvent::LayoutDirectionChange );
+    qskSendEventTo( q_func(), QEvent::LayoutDirectionChange );
 }
 
 void QskQuickItemPrivate::updateControlFlags( QskQuickItem::Flags flags )
@@ -83,18 +81,8 @@ void QskQuickItemPrivate::updateControlFlags( QskQuickItem::Flags flags )
 
 void QskQuickItemPrivate::layoutConstraintChanged()
 {
-    if ( !blockLayoutRequestEvents )
-    {
-        Q_Q( QskQuickItem );
-        if ( auto item = q->parentItem() )
-            qskSendEventTo( item, QEvent::LayoutRequest );
-
-        /*
-            We don't send further LayoutRequest events until someone
-            actively requests a layout relevant information
-         */
-        blockLayoutRequestEvents = true;
-    }
+    if ( auto item = q_func()->parentItem() )
+        qskSendEventTo( item, QEvent::LayoutRequest );
 }
 
 void QskQuickItemPrivate::implicitSizeChanged()
@@ -170,8 +158,6 @@ void QskQuickItemPrivate::setImplicitSize( qreal w, qreal h, bool doNotify )
 
     if ( doNotify )
     {
-        // calling implicitSizeChanged only once, TODO ...
-
         if ( doWidth )
             Inherited::implicitWidthChanged();
 
@@ -180,6 +166,10 @@ void QskQuickItemPrivate::setImplicitSize( qreal w, qreal h, bool doNotify )
     }
 }
 
+/*
+    In case of the application interferes by calling
+    setImplicitWidth or setImplicitHeight manually:
+ */
 void QskQuickItemPrivate::implicitWidthChanged()
 {
     Inherited::implicitWidthChanged();
diff --git a/src/controls/QskQuickItemPrivate.h b/src/controls/QskQuickItemPrivate.h
index 8c05fe03..19260d20 100644
--- a/src/controls/QskQuickItemPrivate.h
+++ b/src/controls/QskQuickItemPrivate.h
@@ -25,9 +25,8 @@ class QskQuickItemPrivate : public QQuickItemPrivate
     void updateControlFlags( QskQuickItem::Flags );
 
   protected:
-    void layoutConstraintChanged();
+    virtual void layoutConstraintChanged();
     virtual void implicitSizeChanged();
-    virtual QSizeF implicitSizeHint() const = 0;
 
   private:
     void cleanupNodes();
@@ -42,6 +41,7 @@ class QskQuickItemPrivate : public QQuickItemPrivate
     void updateImplicitSize( bool doNotify );
 
     void setImplicitSize( qreal width, qreal height, bool doNotify );
+    virtual QSizeF implicitSizeHint() const = 0;
 
   private:
     Q_DECLARE_PUBLIC( QskQuickItem )
@@ -56,9 +56,6 @@ class QskQuickItemPrivate : public QQuickItemPrivate
     bool clearPreviousNodes : 1;
 
     bool isInitiallyPainted : 1;
-
-  protected:
-    mutable bool blockLayoutRequestEvents : 1;
 };
 
 #endif