diff options
author | Bjørn Erik Nilsen <bjorn.nilsen@nokia.com> | 2011-05-02 12:39:45 +0200 |
---|---|---|
committer | Olivier Goffart <olivier.goffart@nokia.com> | 2011-05-11 16:38:49 +0200 |
commit | 1e41e3076aab37f151ffc09e6cd5768289e0d3e9 (patch) | |
tree | 1c5870ebf6dd09fb1f3ebe874ea5dc194a2a5a37 /src | |
parent | 7ee981a834c8b0b8eddf600965a446c5bb124a91 (diff) |
Fixes crash in QWidget::effectiveWinId.
Widgets are left in a transitional (and incosistent) state while being
re-parented, which caused QWidget::effectiveWinId() to crash in certain
circumstances. See patch for more details.
Auto test included.
Reviewed-by: ogoffart
(cherry picked from commit 6db0153cd7e35e4a919a76ae2aadbf2d2510bfb7)
Diffstat (limited to 'src')
-rw-r--r-- | src/gui/kernel/qwidget.cpp | 20 | ||||
-rw-r--r-- | src/gui/kernel/qwidget_p.h | 1 |
2 files changed, 21 insertions, 0 deletions
diff --git a/src/gui/kernel/qwidget.cpp b/src/gui/kernel/qwidget.cpp index 434a788b89..d29a46a14f 100644 --- a/src/gui/kernel/qwidget.cpp +++ b/src/gui/kernel/qwidget.cpp @@ -299,6 +299,7 @@ QWidgetPrivate::QWidgetPrivate(int version) #ifndef QT_NO_IM , inheritsInputMethodHints(0) #endif + , inSetParent(0) #if defined(Q_WS_X11) , picture(0) #elif defined(Q_WS_WIN) @@ -2599,6 +2600,22 @@ WId QWidget::effectiveWinId() const if (id || !testAttribute(Qt::WA_WState_Created)) return id; QWidget *realParent = nativeParentWidget(); + if (!realParent && d_func()->inSetParent) { + // In transitional state. This is really just a workaround. The real problem + // is that QWidgetPrivate::setParent_sys (platform specific code) first sets + // the window id to 0 (setWinId(0)) before it sets the Qt::WA_WState_Created + // attribute to false. The correct way is to do it the other way around, and + // in that case the Qt::WA_WState_Created logic above will kick in and + // return 0 whenever the widget is in a transitional state. However, changing + // the original logic for all platforms is far more intrusive and might + // break existing applications. + // Note: The widget can only be in a transitional state when changing its + // parent -- everything else is an internal error -- hence explicitly checking + // against 'inSetParent' rather than doing an unconditional return whenever + // 'realParent' is 0 (which may cause strange artifacts and headache later). + return 0; + } + // This widget *must* have a native parent widget. Q_ASSERT(realParent); Q_ASSERT(realParent->internalWinId()); return realParent->internalWinId(); @@ -10111,6 +10128,7 @@ void QWidget::setParent(QWidget *parent) void QWidget::setParent(QWidget *parent, Qt::WindowFlags f) { Q_D(QWidget); + d->inSetParent = true; bool resized = testAttribute(Qt::WA_Resized); bool wasCreated = testAttribute(Qt::WA_WState_Created); QWidget *oldtlw = window(); @@ -10271,6 +10289,8 @@ void QWidget::setParent(QWidget *parent, Qt::WindowFlags f) ancestorProxy->d_func()->embedSubWindow(this); } #endif + + d->inSetParent = false; } /*! diff --git a/src/gui/kernel/qwidget_p.h b/src/gui/kernel/qwidget_p.h index 919f8bc3da..ca6983dbff 100644 --- a/src/gui/kernel/qwidget_p.h +++ b/src/gui/kernel/qwidget_p.h @@ -770,6 +770,7 @@ public: #ifndef QT_NO_IM uint inheritsInputMethodHints : 1; #endif + uint inSetParent : 1; // *************************** Platform specific ************************************ #if defined(Q_WS_X11) // <----------------------------------------------------------- X11 |