Clearing QComboBox and then adding items throws NSRangeException

#include "mainwindow.h"
#include "ui_mainwindow.h"

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
{
    comboBox = new QComboBox();
    comboBox->addItem("item 1");
    comboBox->addItem("item 2");
    comboBox->addItem("item 3");
    this->setCentralWidget(comboBox);
}

void MainWindow::keyPressEvent(QKeyEvent* event)
{
    comboBox->clear();
    comboBox->addItem("item 1");
    comboBox->addItem("item 2");
    comboBox->addItem("item 3");
}

MainWindow::~MainWindow()
{
} 

*** Terminating app due to uncaught exception 'NSRangeException', reason: '*** -[__NSArrayM objectAtIndexedSubscript:]: index 0 beyond bounds for empty array'*** First throw call stack:(	0   CoreFoundation                      0x00000001888c4570 __exceptionPreprocess + 176	1   libobjc.A.dylib                     0x00000001883b5eb4 objc_exception_throw + 60	2   CoreFoundation                      0x000000018883ad10 -[__NSCFString hasSuffix:] + 0	3   libqcocoa.dylib                     0x00000001002d6044 _ZN20QCocoaSystemTrayIcon13emitActivatedEv + 274796	4   libqcocoa.dylib                     0x00000001002d60c8 _ZN20QCocoaSystemTrayIcon13emitActivatedEv + 274928	5   libqcocoa.dylib                     0x00000001002d4688 _ZN20QCocoaSystemTrayIcon13emitActivatedEv + 268208	6   QtWidgets                           0x00000001012dd1a8 _ZN9QListView16selectionChangedERK14QItemSelectionS2_ + 204	7   QtCore                              0x00000001021eb48c _ZN11QMetaObject8activateEP7QObjectPKS_iPPv + 3808	8   QtCore                              0x00000001023b1e44 _ZN19QItemSelectionModel20emitSelectionChangedERK14QItemSelectionS2_ + 216	9   QtCore                              0x00000001023b1a2c _ZN19QItemSelectionModel6selectERK14QItemSelection6QFlagsINS_13SelectionFlagEE + 636	10  QtCore                              0x00000001023b170c _ZN19QItemSelectionModel6selectERK11QModelIndex6QFlagsINS_13SelectionFlagEE + 68	11  QtCore                              0x00000001023b28cc _ZN19QItemSelectionModel15setCurrentIndexERK11QModelIndex6QFlagsINS_13SelectionFlagEE + 260	12  QtWidgets                           0x000000010113b338 _ZNK9QComboBox5countEv + 828	13  QtWidgets                           0x000000010113e8b4 _ZN9QComboBoxC1ER16QComboBoxPrivateP7QWidget + 2412	14  QtCore                              0x00000001021eb224 _ZN11QMetaObject8activateEP7QObjectPKS_iPPv + 3192	15  QtCore                              0x000000010239a944 _ZN18QAbstractItemModel13endInsertRowsEv + 200	16  QtGui                               0x00000001007837a4 _ZN18QStandardItemModel11itemChangedEP13QStandardItem + 2376	17  QtWidgets                           0x0000000101141910 _ZN9QComboBox10insertItemEiRK5QIconRK7QStringRK8QVariant + 368	18  comboBoxCrash                       0x0000000100006e04 _ZN9QComboBox10insertItemEiRK7QStringRK8QVariant + 80	19  comboBoxCrash                       0x0000000100006a20 _ZN9QComboBox7addItemERK7QStringRK8QVariant + 56	20  comboBoxCrash                       0x0000000100006b90 _ZN10MainWindow13keyPressEventEP9QKeyEvent + 116	21  QtWidgets                           0x0000000101071a1c _ZN7QWidget5eventEP6QEvent + 488	22  QtWidgets                           0x0000000101190020 _ZN11QMainWindow5eventEP6QEvent + 380	23  QtWidgets                           0x0000000101028594 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent + 272	24  QtWidgets                           0x00000001010295fc _ZN12QApplication6notifyEP7QObjectP6QEvent + 1036	25  QtCore                              0x00000001021a1474 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent + 292	26  QtWidgets                           0x0000000101085abc _ZNK21QWidgetRepaintManager3rhiEv + 7588	27  QtWidgets                           0x0000000101028594 _ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent + 272	28  QtWidgets                           0x00000001010293e8 _ZN12QApplication6notifyEP7QObjectP6QEvent + 504	29  QtCore                              0x00000001021a1474 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent + 292	30  QtGui                               0x00000001004e0178 _ZN22QGuiApplicationPrivate15processKeyEventEPN29QWindowSystemInterfacePrivate8KeyEventE + 252	31  QtGui                               0x000000010053b674 _ZN22QWindowSystemInterface22sendWindowSystemEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE + 408	32  QtGui                               0x000000010053b260 _ZN22QWindowSystemInterface23flushWindowSystemEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE + 524	33  libqcocoa.dylib                     0x00000001002bdb90 _ZN20QCocoaSystemTrayIcon13emitActivatedEv + 175288	34  libqcocoa.dylib                     0x00000001002bea58 _ZN20QCocoaSystemTrayIcon13emitActivatedEv + 179072	35  AppKit                              0x000000018c156810 -[NSWindow(NSEventRouting) _reallySendEvent:isDelayedEvent:] + 480	36  AppKit                              0x000000018c15645c -[NSWindow(NSEventRouting) sendEvent:] + 284	37  libqcocoa.dylib                     0x00000001002c6b14 _ZN20QCocoaSystemTrayIcon13emitActivatedEv + 212028	38  AppKit                              0x000000018c8039f4 -[NSApplication(NSEventRouting) sendEvent:] + 1604	39  libqcocoa.dylib                     0x0000000100269c00 qt_plugin_instance + 1052	40  AppKit                              0x000000018c452908 -[NSApplication _handleEvent:] + 60	41  AppKit                              0x000000018c01dd74 -[NSApplication run] + 512	42  libqcocoa.dylib                     0x00000001002758fc qt_plugin_instance + 49432	43  QtCore                              0x00000001021ab160 _ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE + 540	44  QtCore                              0x00000001021a1b00 _ZN16QCoreApplication4execEv + 112	45  comboBoxCrash                       0x00000001000066d4 main + 108	46  dyld                                0x00000001883f10e0 start + 2360)libc++abi: terminating due to uncaught exception of type NSException