Clean up cancel operation handling on OS X

The logic for handling cancel operations was spread out through
the code base and sometimes hard-coded to only include the Escape
key shortcut, missing the Command+. shortcut.

We now intercept both attempts at cancel operations from the system
through cancelOperation, which we forward as normal key events.

A new QKeySequence::StandardKey has been added for the Cancel sequence,
which maps to Escape on all platforms, and Command+. in addition for
OS X. The hard-coded logic in QWidget and subclasses for dealing
with closing the dialogs has been replaced with this key sequence,
which allows clients to override the behavior. Note that the widget
code is not wrapped in checks for QT_NO_SHORTCUT, as we don't care
about keeping widgets building and working under that define.

The logic in QCocoaWindow to bypass windowShouldClose when delivering
IM events has been removed as we now handle that specific case by
also forwarding Escape as a cancel operation.

Task-number: QTBUG-47557
Task-number: QTBUG-45771
Task-number: QTBUG-44076
Change-Id: Ibe0b3a4819f8659d246a2142dd7d9cd3a826ef78
Reviewed-by: Tim Blechmann <tim@klingt.org>
Reviewed-by: Morten Johan Sørvig <morten.sorvig@theqtcompany.com>
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@theqtcompany.com>

3 files changed, 7 insertions, 2 deletions

diff --git a/src/gui/kernel/qkeysequence.cpp b/src/gui/kernel/qkeysequence.cpp
index ffa9b87147..881d7cc76a 100644
--- a/src/gui/kernel/qkeysequence.cpp
+++ b/src/gui/kernel/qkeysequence.cpp
@@ -291,6 +291,7 @@ void Q_GUI_EXPORT qt_set_sequence_auto_mnemonic(bool b) { qt_sequence_no_mnemoni
     \row    \li InsertParagraphSeparator     \li Enter                    \li Enter                  \li Enter          \li Enter
     \row    \li InsertLineSeparator          \li Shift+Enter              \li Meta+Enter, Meta+O     \li Shift+Enter    \li Shift+Enter
     \row    \li Backspace             \li (none)                          \li Meta+H                 \li (none)         \li (none)
+    \row    \li Cancel                \li Escape                          \li Escape, Ctrl+.         \li Escape         \li Escape
     \endtable
 
     Note that, since the key sequences used for the standard shortcuts differ
@@ -752,6 +753,7 @@ static const struct {
     \value ZoomIn           Zoom in.
     \value ZoomOut          Zoom out.
     \value FullScreen       Toggle the window state to/from full screen.
+    \value Cancel           Cancel the current operation.
 */
 
 /*!
diff --git a/src/gui/kernel/qkeysequence.h b/src/gui/kernel/qkeysequence.h
index d6171c86f2..98a611aab5 100644
--- a/src/gui/kernel/qkeysequence.h
+++ b/src/gui/kernel/qkeysequence.h
@@ -137,7 +137,8 @@ public:
         FullScreen,
         Deselect,
         DeleteCompleteLine,
-        Backspace
+        Backspace,
+        Cancel
      };
      Q_ENUM(StandardKey)
 
diff --git a/src/gui/kernel/qplatformtheme.cpp b/src/gui/kernel/qplatformtheme.cpp
index 36a71fe2da..ce8548f628 100644
--- a/src/gui/kernel/qplatformtheme.cpp
+++ b/src/gui/kernel/qplatformtheme.cpp
@@ -323,7 +323,9 @@ const QKeyBinding QPlatformThemePrivate::keyBindings[] = {
     {QKeySequence::FullScreen,              1,          Qt::Key_F11,                            KB_Win | KB_KDE},
     {QKeySequence::Deselect,                0,          Qt::CTRL | Qt::SHIFT | Qt::Key_A,       KB_X11},
     {QKeySequence::DeleteCompleteLine,      0,          Qt::CTRL | Qt::Key_U,                   KB_X11},
-    {QKeySequence::Backspace,               0,          Qt::META | Qt::Key_H,                   KB_Mac}
+    {QKeySequence::Backspace,               0,          Qt::META | Qt::Key_H,                   KB_Mac},
+    {QKeySequence::Cancel,                  0,          Qt::Key_Escape,                         KB_All},
+    {QKeySequence::Cancel,                  0,          Qt::CTRL | Qt::Key_Period,              KB_Mac}
 };
 
 const uint QPlatformThemePrivate::numberOfKeyBindings = sizeof(QPlatformThemePrivate::keyBindings)/(sizeof(QKeyBinding));