Speed up XmlListModel.

1 files changed, 22 insertions, 7 deletions

diff --git a/src/declarative/extra/qmlxmllistmodel.cpp b/src/declarative/extra/qmlxmllistmodel.cpp
index 62ede80..b10f5fd 100644
--- a/src/declarative/extra/qmlxmllistmodel.cpp
+++ b/src/declarative/extra/qmlxmllistmodel.cpp
@@ -202,11 +202,10 @@ void QmlXmlQuery::doQueryJob()
         QXmlItem item(result.next());
         if (item.isAtomicValue())
             count = item.toAtomicValue().toInt();
-        prefix += QLatin1String("[%1]/");
     }
     //qDebug() << count;
 
-    m_prefix = namespaces + prefix;
+    m_prefix = namespaces + prefix + QLatin1String("/");
     m_data = xml;
     if (count > 0)
         m_size = count;
@@ -222,8 +221,24 @@ void QmlXmlQuery::doSubQueryJob()
     QXmlQuery subquery;
     subquery.bindVariable(QLatin1String("inputDocument"), &b);
 
-    //XXX should we use an array of objects or something else rather than a table?
-    for (int j = 0; j < m_size; ++j) {
+    //### we might be able to condense even further (query for everything in one go)
+    for (int i = 0; i < m_roleObjects->size(); ++i) {
+        XmlListModelRole *role = m_roleObjects->at(i);
+        subquery.setQuery(m_prefix + QLatin1String("(let $v := ") + role->query() + QLatin1String(" return if ($v) then ") + role->query() + QLatin1String(" else \"\")"));
+        QXmlResultItems output3;
+        subquery.evaluateTo(&output3);
+        QXmlItem item(output3.next());
+        QList<QVariant> resultList;
+        while (!item.isNull()) {
+            resultList << item.toAtomicValue();
+            item = output3.next();
+        }
+        m_modelData << resultList;
+        b.seek(0);
+    }
+
+    //XXX this method is much slower, but would work better for incremental loading
+    /*for (int j = 0; j < m_size; ++j) {
         QList<QVariant> resultList;
         for (int i = 0; i < m_roleObjects->size(); ++i) {
             XmlListModelRole *role = m_roleObjects->at(i);
@@ -248,7 +263,7 @@ void QmlXmlQuery::doSubQueryJob()
             b.seek(0);
         }
         m_modelData << resultList;
-    }
+    }*/
 }
 
 
@@ -362,7 +377,7 @@ QHash<int,QVariant> QmlXmlListModel::data(int index, const QList<int> &roles) co
     for (int i = 0; i < roles.size(); ++i) {
         int role = roles.at(i);
         int roleIndex = d->roles.indexOf(role);
-        rv.insert(role, d->data.at(index).at(roleIndex));
+        rv.insert(role, d->data.at(roleIndex).at(index));
     }
     return rv;
 }
@@ -462,8 +477,8 @@ void QmlXmlListModel::reload()
     d->queryId = -1;
 
     //clear existing data
+    int count = d->size;
     d->size = 0;
-    int count = d->data.count();
     d->data.clear();
     if (count > 0)
         emit itemsRemoved(0, count);