From a6b9a82e9cfa902ad39d63316b512b3caf526d22 Mon Sep 17 00:00:00 2001
From: Sergio Martins <sergio.martins@kdab.com>
Date: Sun, 31 Jan 2021 12:59:02 +0000
Subject: [PATCH] Fix crash when hosting QQuickWidget

There's no need to check if invisible widgets are candidates
for docking. There's usually no downside either, except that
QQuickWidget is very sensitive with when its platform window
is created, so don't force the creation.

Will cherry-pick to 1.2 if no regression is found

Fixes #150
---
 Changelog                      | 1 +
 src/private/DragController.cpp | 4 ++++
 2 files changed, 5 insertions(+)

diff --git a/Changelog b/Changelog
index 86ecf413..50c8aeaa 100644
--- a/Changelog
+++ b/Changelog
@@ -13,6 +13,7 @@
   - Fixed drag offset when dragging too fast with mouse
   - Fixed bug where last tab index position wouldn't be remembered in case user
     had manually reordered tabs (#154)
+  - Fixed crash when hosting a QQuickWidget (#150)
 
 * v1.2.1 (unreleased)
   - Support for resizing dock widgets when they are in overlay/popup mode (autohide/sidebar feature)
diff --git a/src/private/DragController.cpp b/src/private/DragController.cpp
index 3f133859..887c0a05 100644
--- a/src/private/DragController.cpp
+++ b/src/private/DragController.cpp
@@ -648,6 +648,10 @@ static QWidgetOrQuick *qtTopLevelForHWND(HWND hwnd)
 {
     const QList<QWindow*> windows = qApp->topLevelWindows();
     for (QWindow *window : windows) {
+        if (!window->isVisible()) {
+            continue;
+        }
+
         if (hwnd == (HWND)window->winId()) {
             return DockRegistry::self()->topLevelForHandle(window);
         }