Fix assertion failure when hiding a SplitView with only one item

Check for -1 when calling handleIndexForSplitIndex().

Change-Id: I81021b64265ace0c47269ea54e538a2725c84b79
Fixes: QTBUG-79270
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@qt.io>

2 files changed, 24 insertions, 4 deletions

diff --git a/src/quicktemplates2/qquicksplitview.cpp b/src/quicktemplates2/qquicksplitview.cpp
index 75cd9674..108dbe07 100644
--- a/src/quicktemplates2/qquicksplitview.cpp
+++ b/src/quicktemplates2/qquicksplitview.cpp
@@ -849,6 +849,8 @@ QQuickSplitViewPrivate::EffectiveSizeData QQuickSplitViewPrivate::effectiveSizeD
 
 int QQuickSplitViewPrivate::handleIndexForSplitIndex(int splitIndex) const
 {
+    // If it's the first and only item in the view, it doesn't have a handle,
+    // so return -1: splitIndex (0) - 1.
     // If it's the last item in the view, it doesn't have a handle, so use
     // the handle for the previous item.
     return splitIndex == contentModel->count() - 1 ? splitIndex - 1 : splitIndex;
@@ -1016,11 +1018,13 @@ void QQuickSplitViewPrivate::itemVisibilityChanged(QQuickItem *item)
     // of the corresponding handle (if one exists).
 
     const int handleIndex = handleIndexForSplitIndex(itemIndex);
-    QQuickItem *handleItem = m_handleItems.at(handleIndex);
-    handleItem->setVisible(item->isVisible());
+    if (handleIndex != -1) {
+        QQuickItem *handleItem = m_handleItems.at(handleIndex);
+        handleItem->setVisible(item->isVisible());
 
-    qCDebug(qlcQQuickSplitView) << "set visible property of handle item"
-        << handleItem << "at index" << handleIndex << "to" << item->isVisible();
+        qCDebug(qlcQQuickSplitView) << "set visible property of handle item"
+            << handleItem << "at index" << handleIndex << "to" << item->isVisible();
+    }
 
     updateHandleVisibilities();
     updateFillIndex();
diff --git a/tests/auto/controls/data/tst_splitview.qml b/tests/auto/controls/data/tst_splitview.qml
index a03c09a0..bd36e898 100644
--- a/tests/auto/controls/data/tst_splitview.qml
+++ b/tests/auto/controls/data/tst_splitview.qml
@@ -1958,4 +1958,20 @@ TestCase {
         mouseRelease(targetHandle, -100, targetHandle.height / 2, Qt.LeftButton)
         verify(!control.resizing)
     }
+
+    Component {
+        id: oneItemComponent
+
+        SplitView {
+            Item {}
+        }
+    }
+
+    // QTBUG-79270
+    function test_hideSplitViewWithOneItem() {
+        var control = createTemporaryObject(oneItemComponent, testCase)
+        verify(control)
+        // Shouldn't be an assertion failure.
+        control.visible = false
+    }
 }