QQmlDelegateModel: provide better warnings

Currently, QQmlDelegateModel errors look like this:

    <Unknown File>: QML VisualDataModel: Error creating delegate

This patch uses the delegate as the QQmlInfo object so that we get
errors with actual file names and line numbers:

    qrc:/main.qml:19:19: QML Component: Error creating delegate

This has several benefits:

- It's obvious which file is causing the issue
- A clickable link in Creator's application output pane

Task-number: QTBUG-49224
Change-Id: I0df0d1a9e898aff5f83131ca62a47cc7f1c74c6e
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>
Reviewed-by: Michael Brasser <michael.brasser@live.com>

1 files changed, 1 insertions, 2 deletions

diff --git a/src/qml/types/qqmldelegatemodel.cpp b/src/qml/types/qqmldelegatemodel.cpp
index 44166e4aa8..c7351b654c 100644
--- a/src/qml/types/qqmldelegatemodel.cpp
+++ b/src/qml/types/qqmldelegatemodel.cpp
@@ -874,7 +874,6 @@ void QQmlDelegateModelPrivate::removeCacheItem(QQmlDelegateModelItem *cacheItem)
 
 void QQmlDelegateModelPrivate::incubatorStatusChanged(QQDMIncubationTask *incubationTask, QQmlIncubator::Status status)
 {
-    Q_Q(QQmlDelegateModel);
     if (!isDoneIncubating(status))
         return;
 
@@ -891,7 +890,7 @@ void QQmlDelegateModelPrivate::incubatorStatusChanged(QQDMIncubationTask *incuba
             emitCreatedItem(incubationTask, cacheItem->object);
         cacheItem->releaseObject();
     } else if (status == QQmlIncubator::Error) {
-        qmlWarning(q, m_delegate->errors()) << "Error creating delegate";
+        qmlWarning(m_delegate, m_delegate->errors()) << "Error creating delegate";
     }
 
     if (!cacheItem->isObjectReferenced()) {