Fix section delegates not updating when changed.

Delete all allocated section items before doing an update when the
section delegate is changed.

Task-number: QTBUG-24899
Change-Id: I09dc7a1c602a49ad7bb37512a7e5116392259457
Reviewed-by: Martin Jones <martin.jones@nokia.com>

1 files changed, 61 insertions, 0 deletions

diff --git a/tests/auto/quick/qquicklistview/data/sectiondelegatechange.qml b/tests/auto/quick/qquicklistview/data/sectiondelegatechange.qml
new file mode 100644
index 0000000000..eee15ed2e0
--- /dev/null
+++ b/tests/auto/quick/qquicklistview/data/sectiondelegatechange.qml
@@ -0,0 +1,61 @@
+import QtQuick 2.0
+
+ListView {
+    width: 240
+    height: 320
+
+    function switchDelegates() {
+        section.delegate = section.delegate === delegate1
+                ? delegate2
+                : delegate1
+    }
+
+    Component {
+        id: delegate1
+
+        Rectangle {
+            objectName: "section1"
+            color: "lightsteelblue"
+            border.width: 1;
+            width: 240
+            height: 25
+
+            Text {
+                anchors.centerIn: parent
+                text: section
+            }
+        }
+    }
+    Component {
+        id: delegate2
+
+        Rectangle {
+            objectName: "section2"
+            color: "yellow"
+            border.width: 1;
+            width: 240
+            height: 50
+
+            Text {
+                anchors.centerIn: parent
+                text: section
+            }
+        }
+    }
+
+    section.property: "modelData"
+    section.delegate: delegate1
+
+    model: 20
+    delegate: Rectangle {
+        objectName: "item"
+        border.width: 1
+        width: 240
+        height: 25
+
+        Text {
+            anchors.centerIn: parent
+            text: modelData
+        }
+    }
+}