Quick: fix expensive iteration over QHash::keys() and QMap::keys()

Change-Id: I21c48214bfddde01f71710705fe01418818a6581
Reviewed-by: Lars Knoll <lars.knoll@theqtcompany.com>

3 files changed, 12 insertions, 8 deletions

diff --git a/src/quick/items/qquickdrag.cpp b/src/quick/items/qquickdrag.cpp
index 279f5e5299..e44c0b216f 100644
--- a/src/quick/items/qquickdrag.cpp
+++ b/src/quick/items/qquickdrag.cpp
@@ -715,9 +715,8 @@ Qt::DropAction QQuickDragAttachedPrivate::startDrag(Qt::DropActions supportedAct
     QDrag *drag = new QDrag(q);
     QMimeData *mimeData = new QMimeData();
 
-    Q_FOREACH (const QString &key, externalMimeData.keys()) {
-        mimeData->setData(key, externalMimeData[key].toString().toUtf8());
-    }
+    for (auto it = externalMimeData.cbegin(), end = externalMimeData.cend(); it != end; ++it)
+        mimeData->setData(it.key(), it.value().toString().toUtf8());
 
     drag->setMimeData(mimeData);
 
diff --git a/src/quick/items/qquickitemanimation.cpp b/src/quick/items/qquickitemanimation.cpp
index 9d140b3156..da577d808a 100644
--- a/src/quick/items/qquickitemanimation.cpp
+++ b/src/quick/items/qquickitemanimation.cpp
@@ -836,12 +836,13 @@ QAbstractAnimationJob* QQuickPathAnimation::transition(QQuickStateActions &actio
         prevData = *d->activeAnimations[target]->pathUpdater();
     }
 
-    QList<QQuickItem*> keys = d->activeAnimations.keys();
-    foreach (QQuickItem *item, keys) {
-        QQuickPathAnimationAnimator *anim = d->activeAnimations.value(item);
+    for (auto it = d->activeAnimations.begin(); it != d->activeAnimations.end();) {
+        QQuickPathAnimationAnimator *anim = it.value();
         if (anim->state() == QAbstractAnimationJob::Stopped) {
             anim->clearTemplate();
-            d->activeAnimations.remove(item);
+            it = d->activeAnimations.erase(it);
+        } else {
+            ++it;
         }
     }
 
diff --git a/src/quick/items/qquickmultipointtoucharea.cpp b/src/quick/items/qquickmultipointtoucharea.cpp
index 9e658cc668..e3a8fe3cc6 100644
--- a/src/quick/items/qquickmultipointtoucharea.cpp
+++ b/src/quick/items/qquickmultipointtoucharea.cpp
@@ -470,7 +470,11 @@ void QQuickMultiPointTouchArea::grabGesture()
     grabMouse();
     setKeepMouseGrab(true);
 
-    grabTouchPoints(_touchPoints.keys().toVector());
+    QVector<int> ids;
+    ids.reserve(_touchPoints.size());
+    for (auto it = _touchPoints.keyBegin(), end = _touchPoints.keyEnd(); it != end; ++it)
+        ids.append(*it);
+    grabTouchPoints(ids);
     setKeepTouchGrab(true);
 }