Particles: fix expensive iteration over QHash::keys()

Change-Id: I02755796e3a5c5a3bb39e125a45d968a750e58e1
Reviewed-by: Lars Knoll <lars.knoll@theqtcompany.com>

2 files changed, 9 insertions, 5 deletions

diff --git a/src/particles/qquickimageparticle.cpp b/src/particles/qquickimageparticle.cpp
index d78a350306..4a79342a89 100644
--- a/src/particles/qquickimageparticle.cpp
+++ b/src/particles/qquickimageparticle.cpp
@@ -1497,9 +1497,10 @@ void QQuickImageParticle::prepareNextFrame(QSGNode **node)
             qDebug() << "QQuickImageParticle Feature level: " << perfLevel;
             qDebug() << "QQuickImageParticle Nodes: ";
             int count = 0;
-            foreach (int i, m_nodes.keys()) {
-                qDebug() << "Group " << i << " (" << m_system->groupData[i]->size() << " particles)";
-                count += m_system->groupData[i]->size();
+            for (auto it = m_nodes.keyBegin(), end = m_nodes.keyEnd(); it != end; ++it) {
+                qDebug() << "Group " << *it << " (" << m_system->groupData[*it]->size()
+                         << " particles)";
+                count += m_system->groupData[*it]->size();
             }
             qDebug() << "Total count: " << count;
         }
diff --git a/src/particles/qquickparticlesystem.cpp b/src/particles/qquickparticlesystem.cpp
index 401d40e275..a91d0df614 100644
--- a/src/particles/qquickparticlesystem.cpp
+++ b/src/particles/qquickparticlesystem.cpp
@@ -995,9 +995,12 @@ void QQuickParticleSystem::createEngine()
     //### Solve the losses if size/states go down
     foreach (QQuickParticleGroup* group, m_groups) {
         bool exists = false;
-        foreach (const QString &name, groupIds.keys())
-            if (group->name() == name)
+        for (auto it = groupIds.keyBegin(), end = groupIds.keyEnd(); it != end; ++it) {
+            if (group->name() == *it) {
                 exists = true;
+                break;
+            }
+        }
         if (!exists) {
             int id = m_nextGroupId++;
             QQuickParticleGroupData* gd = new QQuickParticleGroupData(id, this);