QGAL: clean up size hint refresh code

The code for refreshing size hints of items / user-created anchors now
happens with a graph in full (not simplified). So we don't need to now how
to refresh size hints for complex anchors.

The code for refreshing complex anchors was used also to initialize
the complex anchors (the '_helper' functions). Those were changed to
calculateSizeHints() and refreshSizeHints() doesn't need to be virtual
anymore.

Signed-off-by: Caio Marcelo de Oliveira Filho <caio.oliveira@openbossa.org>
Reviewed-by: Eduardo M. Fleury <eduardo.fleury@openbossa.org>

2 files changed, 25 insertions, 65 deletions

diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
index 7646d4c..2e80857 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.cpp
@@ -167,7 +167,7 @@ static void internalSizeHints(QSizePolicy::Policy policy,
         *prefSize = prefSizeHint;
 }
 
-bool AnchorData::refreshSizeHints(const QLayoutStyleInfo *styleInfo)
+void AnchorData::refreshSizeHints(const QLayoutStyleInfo *styleInfo)
 {
     QSizePolicy::Policy policy;
     qreal minSizeHint;
@@ -182,7 +182,7 @@ bool AnchorData::refreshSizeHints(const QLayoutStyleInfo *styleInfo)
             maxSize = QWIDGETSIZE_MAX;
             if (isCenterAnchor)
                 maxSize /= 2;
-            return true;
+            return;
         } else {
             if (orientation == QGraphicsAnchorLayoutPrivate::Horizontal) {
                 policy = item->sizePolicy().horizontalPolicy();
@@ -244,8 +244,6 @@ bool AnchorData::refreshSizeHints(const QLayoutStyleInfo *styleInfo)
     sizeAtMinimum = prefSize;
     sizeAtPreferred = prefSize;
     sizeAtMaximum = prefSize;
-
-    return true;
 }
 
 void ParallelAnchorData::updateChildrenSizes()
@@ -274,18 +272,11 @@ void ParallelAnchorData::updateChildrenSizes()
     secondEdge->updateChildrenSizes();
 }
 
-bool ParallelAnchorData::refreshSizeHints(const QLayoutStyleInfo *styleInfo)
+bool ParallelAnchorData::calculateSizeHints()
 {
-    return refreshSizeHints_helper(styleInfo);
-}
-
-bool ParallelAnchorData::refreshSizeHints_helper(const QLayoutStyleInfo *styleInfo,
-                                                 bool refreshChildren)
-{
-    if (refreshChildren && (!firstEdge->refreshSizeHints(styleInfo)
-                            || !secondEdge->refreshSizeHints(styleInfo))) {
-        return false;
-    }
+    // Note that parallel groups can lead to unfeasibility, so during calculation, we can
+    // find out one unfeasibility. Because of that this method return boolean. This can't
+    // happen in sequential, so there the method is void.
 
     // Account for parallel anchors where the second edge is backwards.
     // We rely on the fact that a forward anchor of sizes min, pref, max is equivalent
@@ -423,13 +414,7 @@ void SequentialAnchorData::updateChildrenSizes()
     }
 }
 
-bool SequentialAnchorData::refreshSizeHints(const QLayoutStyleInfo *styleInfo)
-{
-    return refreshSizeHints_helper(styleInfo);
-}
-
-bool SequentialAnchorData::refreshSizeHints_helper(const QLayoutStyleInfo *styleInfo,
-                                                   bool refreshChildren)
+void SequentialAnchorData::calculateSizeHints()
 {
     minSize = 0;
     prefSize = 0;
@@ -437,11 +422,6 @@ bool SequentialAnchorData::refreshSizeHints_helper(const QLayoutStyleInfo *style
 
     for (int i = 0; i < m_edges.count(); ++i) {
         AnchorData *edge = m_edges.at(i);
-
-        // If it's the case refresh children information first
-        if (refreshChildren && !edge->refreshSizeHints(styleInfo))
-            return false;
-
         minSize += edge->minSize;
         prefSize += edge->prefSize;
         maxSize += edge->maxSize;
@@ -451,8 +431,6 @@ bool SequentialAnchorData::refreshSizeHints_helper(const QLayoutStyleInfo *style
     sizeAtMinimum = prefSize;
     sizeAtPreferred = prefSize;
     sizeAtMaximum = prefSize;
-
-    return true;
 }
 
 #ifdef QT_DEBUG
@@ -627,7 +605,7 @@ AnchorData *QGraphicsAnchorLayoutPrivate::addAnchorMaybeParallel(AnchorData *new
 
         // At this point we can identify that the parallel anchor is not feasible, e.g. one
         // anchor minimum size is bigger than the other anchor maximum size.
-        *feasible = parallel->refreshSizeHints_helper(0, false);
+        *feasible = parallel->calculateSizeHints();
         newAnchor = parallel;
     }
 
@@ -688,7 +666,7 @@ static AnchorData *createSequence(Graph<AnchorVertex, AnchorData> *graph,
     sequence->from = before;
     sequence->to = after;
 
-    sequence->refreshSizeHints_helper(0, false);
+    sequence->calculateSizeHints();
 
     return sequence;
 }
@@ -1335,11 +1313,11 @@ void QGraphicsAnchorLayoutPrivate::createItemEdges(QGraphicsLayoutItem *item)
     // refresh its size hint / policy values.
     AnchorData *data = new AnchorData;
     addAnchor_helper(item, Qt::AnchorLeft, item, Qt::AnchorRight, data);
-    data->refreshSizeHints(0); // 0 = effectiveSpacing, will not be used
+    data->refreshSizeHints();
 
     data = new AnchorData;
     addAnchor_helper(item, Qt::AnchorTop, item, Qt::AnchorBottom, data);
-    data->refreshSizeHints(0); // 0 = effectiveSpacing, will not be used
+    data->refreshSizeHints();
 }
 
 /*!
@@ -1399,14 +1377,14 @@ void QGraphicsAnchorLayoutPrivate::createCenterAnchors(
     addAnchor_helper(item, firstEdge, item, centerEdge, data);
     data->isCenterAnchor = true;
     data->dependency = AnchorData::Master;
-    data->refreshSizeHints(0);
+    data->refreshSizeHints();
 
     data = new AnchorData;
     c->variables.insert(data, -1.0);
     addAnchor_helper(item, centerEdge, item, lastEdge, data);
     data->isCenterAnchor = true;
     data->dependency = AnchorData::Slave;
-    data->refreshSizeHints(0);
+    data->refreshSizeHints();
 
     itemCenterConstraints[orientation].append(c);
 
@@ -1473,7 +1451,7 @@ void QGraphicsAnchorLayoutPrivate::removeCenterAnchors(
         // Create the new anchor that should substitute the left-center-right anchors.
         AnchorData *data = new AnchorData;
         addAnchor_helper(item, firstEdge, item, lastEdge, data);
-        data->refreshSizeHints(0);
+        data->refreshSizeHints();
 
         // Remove old anchors
         removeAnchor_helper(first, center);
@@ -1995,12 +1973,8 @@ void QGraphicsAnchorLayoutPrivate::calculateGraphs(
 
     static bool simplificationEnabled = qgetenv("QT_ANCHORLAYOUT_NO_SIMPLIFICATION").isEmpty();
 
-    // Reset the nominal sizes of each anchor based on the current item sizes.
-    if (!refreshAllSizeHints(orientation)) {
-        qWarning("QGraphicsAnchorLayout: anchor setup is not feasible.");
-        graphHasConflicts[orientation] = true;
-        return;
-    }
+    // Reset the nominal sizes of each anchor based on the current item sizes
+    refreshAllSizeHints(orientation);
 
     // Simplify the graph
     if (simplificationEnabled && !simplifyGraph(orientation)) {
@@ -2169,29 +2143,19 @@ bool QGraphicsAnchorLayoutPrivate::calculateNonTrunk(const QList<QSimplexConstra
 /*!
     \internal
 
-    Traverse the graph refreshing the size hints. Complex anchors will call the
-    refresh method of their children anchors. Simple anchors, if are internal
-    anchors, will query the associated item for their size hints.
-
-    Returns false if some unfeasibility was found in the graph regarding the
-    complex anchors.
+    Traverse the graph refreshing the size hints. Edges will query their associated
+    item or graphicsAnchor for their size hints.
 */
-bool QGraphicsAnchorLayoutPrivate::refreshAllSizeHints(Orientation orientation)
+void QGraphicsAnchorLayoutPrivate::refreshAllSizeHints(Orientation orientation)
 {
     Graph<AnchorVertex, AnchorData> &g = graph[orientation];
     QList<QPair<AnchorVertex *, AnchorVertex *> > vertices = g.connections();
 
     QLayoutStyleInfo styleInf = styleInfo();
     for (int i = 0; i < vertices.count(); ++i) {
-        AnchorData *data = g.edgeData(vertices.at(i).first, vertices.at(i).second);;
-        Q_ASSERT(data->from && data->to);
-
-        // During the traversal we check the feasibility of the complex anchors.
-        if (!data->refreshSizeHints(&styleInf))
-            return false;
+        AnchorData *data = g.edgeData(vertices.at(i).first, vertices.at(i).second);
+        data->refreshSizeHints(&styleInf);
     }
-
-    return true;
 }
 
 /*!
diff --git a/src/gui/graphicsview/qgraphicsanchorlayout_p.h b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
index fd82dd9..2b365fb 100644
--- a/src/gui/graphicsview/qgraphicsanchorlayout_p.h
+++ b/src/gui/graphicsview/qgraphicsanchorlayout_p.h
@@ -131,7 +131,7 @@ struct AnchorData : public QSimplexVariable {
           dependency(Independent) {}
 
     virtual void updateChildrenSizes() {}
-    virtual bool refreshSizeHints(const QLayoutStyleInfo *styleInfo);
+    void refreshSizeHints(const QLayoutStyleInfo *styleInfo = 0);
 
     virtual ~AnchorData() {}
 
@@ -197,9 +197,7 @@ struct SequentialAnchorData : public AnchorData
     }
 
     virtual void updateChildrenSizes();
-    virtual bool refreshSizeHints(const QLayoutStyleInfo *styleInfo);
-
-    bool refreshSizeHints_helper(const QLayoutStyleInfo *styleInfo, bool refreshChildren = true);
+    void calculateSizeHints();
 
     QVector<AnchorVertex*> m_children;          // list of vertices in the sequence
     QVector<AnchorData*> m_edges;               // keep the list of edges too.
@@ -226,9 +224,7 @@ struct ParallelAnchorData : public AnchorData
     }
 
     virtual void updateChildrenSizes();
-    virtual bool refreshSizeHints(const QLayoutStyleInfo *styleInfo);
-
-    bool refreshSizeHints_helper(const QLayoutStyleInfo *styleInfo, bool refreshChildren = true);
+    bool calculateSizeHints();
 
     AnchorData* firstEdge;
     AnchorData* secondEdge;
@@ -483,7 +479,7 @@ public:
                            const QList<AnchorData *> &variables);
 
     // Support functions for calculateGraph()
-    bool refreshAllSizeHints(Orientation orientation);
+    void refreshAllSizeHints(Orientation orientation);
     void findPaths(Orientation orientation);
     void constraintsFromPaths(Orientation orientation);
     void updateAnchorSizes(Orientation orientation);